Adding upstream version 1:10.5.12.upstream/1%10.5.12upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 11959 insertions, 0 deletions

diff --git a/sql/ha_partition.cc b/sql/ha_partition.cc
new file mode 100644
index 00000000..2c60a98d
--- /dev/null
+++ b/sql/ha_partition.cc
@@ -0,0 +1,11959 @@
+/*
+  Copyright (c) 2005, 2019, Oracle and/or its affiliates.
+  Copyright (c) 2009, 2021, MariaDB
+
+  This program is free software; you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation; version 2 of the License.
+
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1335  USA
+*/
+
+/*
+  This handler was developed by Mikael Ronstrom for version 5.1 of MySQL.
+  It is an abstraction layer on top of other handlers such as MyISAM,
+  InnoDB, Federated, Berkeley DB and so forth. Partitioned tables can also
+  be handled by a storage engine. The current example of this is NDB
+  Cluster that has internally handled partitioning. This have benefits in
+  that many loops needed in the partition handler can be avoided.
+
+  Partitioning has an inherent feature which in some cases is positive and
+  in some cases is negative. It splits the data into chunks. This makes
+  the data more manageable, queries can easily be parallelised towards the
+  parts and indexes are split such that there are less levels in the
+  index trees. The inherent disadvantage is that to use a split index
+  one has to scan all index parts which is ok for large queries but for
+  small queries it can be a disadvantage.
+
+  Partitioning lays the foundation for more manageable databases that are
+  extremely large. It does also lay the foundation for more parallelism
+  in the execution of queries. This functionality will grow with later
+  versions of MySQL/MariaDB.
+
+  The partition is setup to use table locks. It implements an partition "SHARE"
+  that is inserted into a hash by table name. You can use this to store
+  information of state that any partition handler object will be able to see
+  if it is using the same table.
+
+  Please read the object definition in ha_partition.h before reading the rest
+  if this file.
+*/
+
+#include "mariadb.h"
+#include "sql_priv.h"
+#include "sql_parse.h"                          // append_file_to_dir
+#include "create_options.h"
+
+#ifdef WITH_PARTITION_STORAGE_ENGINE
+#include "ha_partition.h"
+#include "sql_table.h"                        // tablename_to_filename
+#include "key.h"
+#include "sql_plugin.h"
+#include "sql_show.h"                        // append_identifier
+#include "sql_admin.h"                       // SQL_ADMIN_MSG_TEXT_SIZE
+#include "sql_select.h"
+
+#include "debug_sync.h"
+
+/* First 4 bytes in the .par file is the number of 32-bit words in the file */
+#define PAR_WORD_SIZE 4
+/* offset to the .par file checksum */
+#define PAR_CHECKSUM_OFFSET 4
+/* offset to the total number of partitions */
+#define PAR_NUM_PARTS_OFFSET 8
+/* offset to the engines array */
+#define PAR_ENGINES_OFFSET 12
+#define PARTITION_ENABLED_TABLE_FLAGS (HA_FILE_BASED | \
+                                       HA_REC_NOT_IN_SEQ | \
+                                       HA_CAN_REPAIR | \
+                                       HA_REUSES_FILE_NAMES)
+#define PARTITION_DISABLED_TABLE_FLAGS (HA_CAN_GEOMETRY | \
+                                        HA_DUPLICATE_POS | \
+                                        HA_CAN_INSERT_DELAYED | \
+                                        HA_READ_BEFORE_WRITE_REMOVAL |\
+                                        HA_CAN_TABLES_WITHOUT_ROLLBACK)
+
+static const char *ha_par_ext= PAR_EXT;
+
+/****************************************************************************
+                MODULE create/delete handler object
+****************************************************************************/
+
+static handler *partition_create_handler(handlerton *hton,
+                                         TABLE_SHARE *share,
+                                         MEM_ROOT *mem_root);
+static uint partition_flags();
+static alter_table_operations alter_table_flags(alter_table_operations flags);
+
+
+int ha_partition::notify_tabledef_changed(LEX_CSTRING *db,
+                                          LEX_CSTRING *org_table_name,
+                                          LEX_CUSTRING *frm,
+                                          LEX_CUSTRING *version)
+{
+  char from_buff[FN_REFLEN + 1], from_lc_buff[FN_REFLEN + 1];
+  const char *from_path, *name_buffer_ptr, *from;
+  int res= 0;
+  handler **file= m_file;
+  DBUG_ENTER("ha_partition::notify_tabledef_changed");
+
+  from= table->s->normalized_path.str;
+
+  /* setup m_name_buffer_ptr */
+  if (read_par_file(table->s->normalized_path.str))
+    DBUG_RETURN(1);
+
+  from_path= get_canonical_filename(*file, from, from_lc_buff);
+  name_buffer_ptr= m_name_buffer_ptr;
+  do
+  {
+    LEX_CSTRING table_name;
+    const char *table_name_ptr;
+    if (create_partition_name(from_buff, sizeof(from_buff),
+                              from_path, name_buffer_ptr,
+                              NORMAL_PART_NAME, FALSE))
+      res=1;
+    table_name_ptr= from_buff + dirname_length(from_buff);
+
+    lex_string_set3(&table_name, table_name_ptr, strlen(table_name_ptr));
+
+    if (((*file)->ht)->notify_tabledef_changed((*file)->ht, db, &table_name,
+                                               frm, version, *file))
+      res=1;
+    name_buffer_ptr= strend(name_buffer_ptr) + 1;
+  } while (*(++file));
+  DBUG_RETURN(res);
+}
+
+
+static int
+partition_notify_tabledef_changed(handlerton *,
+                                  LEX_CSTRING *db,
+                                  LEX_CSTRING *table,
+                                  LEX_CUSTRING *frm,
+                                  LEX_CUSTRING *version,
+                                  handler *file)
+{
+  DBUG_ENTER("partition_notify_tabledef_changed");
+  DBUG_RETURN(static_cast<ha_partition*>
+              (file)->notify_tabledef_changed(db, table, frm, version));
+}
+
+
+/*
+  If frm_error() is called then we will use this to to find out what file
+  extensions exist for the storage engine. This is also used by the default
+  rename_table and delete_table method in handler.cc.
+*/
+static const char *ha_partition_ext[]=
+{
+  ha_par_ext, NullS
+};
+
+static PSI_memory_key key_memory_Partition_share;
+static PSI_memory_key key_memory_partition_sort_buffer;
+static PSI_memory_key key_memory_Partition_admin;
+
+static PSI_memory_key key_memory_ha_partition_file;
+//static PSI_memory_key key_memory_ha_partition_engine_array;
+static PSI_memory_key key_memory_ha_partition_part_ids;
+
+#ifdef HAVE_PSI_INTERFACE
+PSI_mutex_key key_partition_auto_inc_mutex;
+PSI_file_key key_file_ha_partition_par;
+
+static PSI_mutex_info all_partition_mutexes[]=
+{
+  { &key_partition_auto_inc_mutex, "Partition_share::auto_inc_mutex", 0}
+};
+static PSI_memory_info all_partitioning_memory[]=
+{ { &key_memory_Partition_share, "Partition_share", 0},
+  { &key_memory_partition_sort_buffer, "partition_sort_buffer", 0},
+  { &key_memory_Partition_admin, "Partition_admin", 0},
+  { &key_memory_ha_partition_file, "ha_partition::file", 0},
+//  { &key_memory_ha_partition_engine_array, "ha_partition::engine_array", 0},
+  { &key_memory_ha_partition_part_ids, "ha_partition::part_ids", 0} };
+static PSI_file_info all_partition_file[]=
+{ { &key_file_ha_partition_par, "ha_partition::parfile", 0} };
+
+static void init_partition_psi_keys(void)
+{
+  const char* category= "partition";
+  int count;
+
+  count= array_elements(all_partitioning_memory);
+  mysql_memory_register(category, all_partitioning_memory, count);
+  count= array_elements(all_partition_mutexes);
+  mysql_mutex_register(category, all_partition_mutexes, count);
+  count= array_elements(all_partition_file);
+  mysql_file_register(category, all_partition_file, count);
+}
+#endif /* HAVE_PSI_INTERFACE */
+
+static int partition_initialize(void *p)
+{
+  handlerton *partition_hton;
+  partition_hton= (handlerton *)p;
+
+  partition_hton->db_type= DB_TYPE_PARTITION_DB;
+  partition_hton->create= partition_create_handler;
+
+  partition_hton->partition_flags= partition_flags;
+  partition_hton->notify_tabledef_changed= partition_notify_tabledef_changed;
+  partition_hton->alter_table_flags= alter_table_flags;
+  partition_hton->flags= HTON_NOT_USER_SELECTABLE |
+                         HTON_HIDDEN |
+                         HTON_TEMPORARY_NOT_SUPPORTED;
+  partition_hton->tablefile_extensions= ha_partition_ext;
+
+#ifdef HAVE_PSI_INTERFACE
+  init_partition_psi_keys();
+#endif
+  return 0;
+}
+
+
+/**
+  Initialize and allocate space for partitions shares.
+
+  @param num_parts  Number of partitions to allocate storage for.
+
+  @return Operation status.
+    @retval true  Failure (out of memory).
+    @retval false Success.
+*/
+
+bool Partition_share::init(uint num_parts)
+{
+  DBUG_ENTER("Partition_share::init");
+  auto_inc_initialized= false;
+  partition_name_hash_initialized= false;
+  next_auto_inc_val= 0;
+  if (partitions_share_refs.init(num_parts))
+  {
+    DBUG_RETURN(true);
+  }
+  DBUG_RETURN(false);
+}
+
+
+/*
+  Create new partition handler
+
+  SYNOPSIS
+    partition_create_handler()
+    table                       Table object
+
+  RETURN VALUE
+    New partition object
+*/
+
+static handler *partition_create_handler(handlerton *hton,
+                                         TABLE_SHARE *share,
+                                         MEM_ROOT *mem_root)
+{
+  ha_partition *file= new (mem_root) ha_partition(hton, share);
+  if (file && file->initialize_partition(mem_root))
+  {
+    delete file;
+    file= 0;
+  }
+  return file;
+}
+
+static uint partition_flags()
+{
+  return HA_CAN_PARTITION;
+}
+
+static alter_table_operations alter_table_flags(alter_table_operations flags __attribute__((unused)))
+{
+  return (HA_PARTITION_FUNCTION_SUPPORTED |
+          HA_FAST_CHANGE_PARTITION);
+}
+
+/*
+  Constructor method
+
+  SYNOPSIS
+    ha_partition()
+    table                       Table object
+
+  RETURN VALUE
+    NONE
+*/
+
+ha_partition::ha_partition(handlerton *hton, TABLE_SHARE *share)
+  :handler(hton, share)
+{
+  DBUG_ENTER("ha_partition::ha_partition(table)");
+  ha_partition_init();
+  DBUG_VOID_RETURN;
+}
+
+
+/* Initialize all partition variables */
+
+void ha_partition::ha_partition_init()
+{
+  init_alloc_root(PSI_INSTRUMENT_ME, &m_mem_root, 512, 512, MYF(0));
+  init_handler_variables();
+}
+
+/*
+  Constructor method
+
+  SYNOPSIS
+    ha_partition()
+    part_info                       Partition info
+
+  RETURN VALUE
+    NONE
+*/
+
+ha_partition::ha_partition(handlerton *hton, partition_info *part_info)
+  :handler(hton, NULL)
+{
+  DBUG_ENTER("ha_partition::ha_partition(part_info)");
+  DBUG_ASSERT(part_info);
+  ha_partition_init();
+  m_part_info= part_info;
+  m_create_handler= TRUE;
+  m_is_sub_partitioned= m_part_info->is_sub_partitioned();
+  DBUG_VOID_RETURN;
+}
+
+/**
+  ha_partition constructor method used by ha_partition::clone()
+
+  @param hton               Handlerton (partition_hton)
+  @param share              Table share object
+  @param part_info_arg      partition_info to use
+  @param clone_arg          ha_partition to clone
+  @param clme_mem_root_arg  MEM_ROOT to use
+
+  @return New partition handler
+*/
+
+ha_partition::ha_partition(handlerton *hton, TABLE_SHARE *share,
+                           partition_info *part_info_arg,
+                           ha_partition *clone_arg,
+                           MEM_ROOT *clone_mem_root_arg)
+  :handler(hton, share)
+{
+  DBUG_ENTER("ha_partition::ha_partition(clone)");
+  ha_partition_init();
+  m_part_info= part_info_arg;
+  m_create_handler= TRUE;
+  m_is_sub_partitioned= m_part_info->is_sub_partitioned();
+  m_is_clone_of= clone_arg;
+  m_clone_mem_root= clone_mem_root_arg;
+  part_share= clone_arg->part_share;
+  m_tot_parts= clone_arg->m_tot_parts;
+  DBUG_VOID_RETURN;
+}
+
+/*
+  Initialize handler object
+
+  SYNOPSIS
+    init_handler_variables()
+
+  RETURN VALUE
+    NONE
+*/
+
+void ha_partition::init_handler_variables()
+{
+  active_index= MAX_KEY;
+  m_mode= 0;
+  m_open_test_lock= 0;
+  m_file_buffer= NULL;
+  m_name_buffer_ptr= NULL;
+  m_engine_array= NULL;
+  m_connect_string= NULL;
+  m_file= NULL;
+  m_file_tot_parts= 0;
+  m_reorged_file= NULL;
+  m_new_file= NULL;
+  m_reorged_parts= 0;
+  m_added_file= NULL;
+  m_tot_parts= 0;
+  m_part_spec.start_part= NO_CURRENT_PART_ID;
+  m_scan_value= 2;
+  m_ref_length= 0;
+  m_part_spec.end_part= NO_CURRENT_PART_ID;
+  m_index_scan_type= partition_no_index_scan;
+  m_start_key.key= NULL;
+  m_start_key.length= 0;
+  m_myisam= FALSE;
+  m_innodb= FALSE;
+  m_extra_cache= FALSE;
+  m_extra_cache_size= 0;
+  m_extra_prepare_for_update= FALSE;
+  m_extra_cache_part_id= NO_CURRENT_PART_ID;
+  m_handler_status= handler_not_initialized;
+  m_part_field_array= NULL;
+  m_ordered_rec_buffer= NULL;
+  m_top_entry= NO_CURRENT_PART_ID;
+  m_rec_length= 0;
+  m_last_part= 0;
+  m_rec0= 0;
+  m_err_rec= NULL;
+  m_curr_key_info[0]= NULL;
+  m_curr_key_info[1]= NULL;
+  m_part_func_monotonicity_info= NON_MONOTONIC;
+  m_key_not_found= FALSE;
+  auto_increment_lock= FALSE;
+  auto_increment_safe_stmt_log_lock= FALSE;
+  /*
+    this allows blackhole to work properly
+  */
+  m_num_locks= 0;
+  m_part_info= NULL;
+  m_create_handler= FALSE;
+  m_is_sub_partitioned= 0;
+  m_is_clone_of= NULL;
+  m_clone_mem_root= NULL;
+  part_share= NULL;
+  m_new_partitions_share_refs.empty();
+  m_part_ids_sorted_by_num_of_records= NULL;
+  m_partitions_to_open= NULL;
+
+  m_range_info= NULL;
+  m_mrr_full_buffer_size= 0;
+  m_mrr_new_full_buffer_size= 0;
+  m_mrr_full_buffer= NULL;
+  m_mrr_range_first= NULL;
+
+  m_pre_calling= FALSE;
+  m_pre_call_use_parallel= FALSE;
+
+  ft_first= ft_current=  NULL;
+  bulk_access_executing= FALSE;                 // For future
+
+  /*
+    Clear bitmaps to allow on one to call my_bitmap_free() on them at any time
+  */
+  my_bitmap_clear(&m_bulk_insert_started);
+  my_bitmap_clear(&m_locked_partitions);
+  my_bitmap_clear(&m_partitions_to_reset);
+  my_bitmap_clear(&m_key_not_found_partitions);
+  my_bitmap_clear(&m_mrr_used_partitions);
+  my_bitmap_clear(&m_opened_partitions);
+  m_file_sample= NULL;
+
+#ifdef DONT_HAVE_TO_BE_INITALIZED
+  m_start_key.flag= 0;
+  m_ordered= TRUE;
+#endif
+}
+
+
+const char *ha_partition::table_type() const
+{
+  // we can do this since we only support a single engine type
+  return m_file[0]->table_type();
+}
+
+
+/*
+  Destructor method
+
+  SYNOPSIS
+    ~ha_partition()
+
+  RETURN VALUE
+    NONE
+*/
+
+ha_partition::~ha_partition()
+{
+  DBUG_ENTER("ha_partition::~ha_partition");
+  if (m_new_partitions_share_refs.elements)
+    m_new_partitions_share_refs.delete_elements();
+  if (m_file != NULL)
+  {
+    uint i;
+    for (i= 0; i < m_tot_parts; i++)
+      delete m_file[i];
+  }
+  destroy_record_priority_queue();
+  my_free(m_part_ids_sorted_by_num_of_records);
+
+  if (m_added_file)
+  {
+    for (handler **ph= m_added_file; *ph; ph++)
+      delete (*ph);
+  }
+  clear_handler_file();
+  free_root(&m_mem_root, MYF(0));
+
+  DBUG_VOID_RETURN;
+}
+
+
+/*
+  Initialize partition handler object
+
+  SYNOPSIS
+    initialize_partition()
+    mem_root			Allocate memory through this
+
+  RETURN VALUE
+    1                         Error
+    0                         Success
+
+  DESCRIPTION
+
+  The partition handler is only a layer on top of other engines. Thus it
+  can't really perform anything without the underlying handlers. Thus we
+  add this method as part of the allocation of a handler object.
+
+  1) Allocation of underlying handlers
+     If we have access to the partition info we will allocate one handler
+     instance for each partition.
+  2) Allocation without partition info
+     The cases where we don't have access to this information is when called
+     in preparation for delete_table and rename_table and in that case we
+     only need to set HA_FILE_BASED. In that case we will use the .par file
+     that contains information about the partitions and their engines and
+     the names of each partition.
+  3) Table flags initialisation
+     We need also to set table flags for the partition handler. This is not
+     static since it depends on what storage engines are used as underlying
+     handlers.
+     The table flags is set in this routine to simulate the behaviour of a
+     normal storage engine
+     The flag HA_FILE_BASED will be set independent of the underlying handlers
+  4) Index flags initialisation
+     When knowledge exists on the indexes it is also possible to initialize the
+     index flags. Again the index flags must be initialized by using the under-
+     lying handlers since this is storage engine dependent.
+     The flag HA_READ_ORDER will be reset for the time being to indicate no
+     ordered output is available from partition handler indexes. Later a merge
+     sort will be performed using the underlying handlers.
+  5) has_transactions are calculated here.
+
+*/
+
+bool ha_partition::initialize_partition(MEM_ROOT *mem_root)
+{
+  handler **file_array, *file;
+  ulonglong check_table_flags;
+  DBUG_ENTER("ha_partition::initialize_partition");
+
+  if (m_create_handler)
+  {
+    m_tot_parts= m_part_info->get_tot_partitions();
+    DBUG_ASSERT(m_tot_parts > 0);
+    if (new_handlers_from_part_info(mem_root))
+      DBUG_RETURN(1);
+  }
+  else if (!table_share || !table_share->normalized_path.str)
+  {
+    /*
+      Called with dummy table share (delete, rename and alter table).
+      Don't need to set-up anything.
+    */
+    DBUG_RETURN(0);
+  }
+  else if (get_from_handler_file(table_share->normalized_path.str,
+                                 mem_root, false))
+  {
+    my_error(ER_FAILED_READ_FROM_PAR_FILE, MYF(0));
+    DBUG_RETURN(1);
+  }
+  /*
+    We create all underlying table handlers here. We do it in this special
+    method to be able to report allocation errors.
+
+    Set up has_transactions since they are called often in all kinds of places,
+    other parameters are calculated on demand.
+    Verify that all partitions have the same table_flags.
+  */
+  check_table_flags= m_file[0]->ha_table_flags();
+  file_array= m_file;
+  do
+  {
+    file= *file_array;
+    if (check_table_flags != file->ha_table_flags())
+    {
+      my_error(ER_MIX_HANDLER_ERROR, MYF(0));
+      DBUG_RETURN(1);
+    }
+  } while (*(++file_array));
+  m_handler_status= handler_initialized;
+  DBUG_RETURN(0);
+}
+
+/****************************************************************************
+                MODULE meta data changes
+****************************************************************************/
+/*
+  Delete a table
+
+  SYNOPSIS
+    delete_table()
+    name                    Full path of table name
+
+  RETURN VALUE
+    >0                        Error
+    0                         Success
+
+  DESCRIPTION
+    Used to delete a table. By the time delete_table() has been called all
+    opened references to this table will have been closed (and your globally
+    shared references released. The variable name will just be the name of
+    the table. You will need to remove any files you have created at this
+    point.
+
+    If you do not implement this, the default delete_table() is called from
+    handler.cc and it will delete all files with the file extensions returned
+    by bas_ext().
+
+    Called from handler.cc by delete_table and  ha_create_table(). Only used
+    during create if the table_flag HA_DROP_BEFORE_CREATE was specified for
+    the storage engine.
+*/
+
+int ha_partition::delete_table(const char *name)
+{
+  DBUG_ENTER("ha_partition::delete_table");
+
+  DBUG_RETURN(del_ren_table(name, NULL));
+}
+
+
+/*
+  Rename a table
+
+  SYNOPSIS
+    rename_table()
+    from                      Full path of old table name
+    to                        Full path of new table name
+
+  RETURN VALUE
+    >0                        Error
+    0                         Success
+
+  DESCRIPTION
+    Renames a table from one name to another from alter table call.
+
+    If you do not implement this, the default rename_table() is called from
+    handler.cc and it will rename all files with the file extensions returned
+    by bas_ext().
+
+    Called from sql_table.cc by mysql_rename_table().
+*/
+
+int ha_partition::rename_table(const char *from, const char *to)
+{
+  DBUG_ENTER("ha_partition::rename_table");
+
+  DBUG_RETURN(del_ren_table(from, to));
+}
+
+
+/*
+  Create the handler file (.par-file)
+
+  SYNOPSIS
+    create_partitioning_metadata()
+    path                              Path to the new frm file (without ext)
+    old_p                             Path to the old frm file (without ext)
+    create_info                       Create info generated for CREATE TABLE
+
+  RETURN VALUE
+    >0                        Error
+    0                         Success
+
+  DESCRIPTION
+    create_partitioning_metadata is called to create any handler specific files
+    before opening the file with openfrm to later call ::create on the
+    file object.
+    In the partition handler this is used to store the names of partitions
+    and types of engines in the partitions.
+*/
+
+int ha_partition::create_partitioning_metadata(const char *path,
+                                               const char *old_path,
+                                               chf_create_flags action_flag)
+{
+  partition_element *part;
+  DBUG_ENTER("ha_partition::create_partitioning_metadata");
+
+  /*
+    We need to update total number of parts since we might write the handler
+    file as part of a partition management command
+  */
+  if (action_flag == CHF_DELETE_FLAG ||
+      action_flag == CHF_RENAME_FLAG)
+  {
+    char name[FN_REFLEN];
+    char old_name[FN_REFLEN];
+
+    strxmov(name, path, ha_par_ext, NullS);
+    strxmov(old_name, old_path, ha_par_ext, NullS);
+    if ((action_flag == CHF_DELETE_FLAG &&
+         mysql_file_delete(key_file_ha_partition_par, name, MYF(MY_WME))) ||
+        (action_flag == CHF_RENAME_FLAG &&
+         mysql_file_rename(key_file_ha_partition_par, old_name, name,
+                           MYF(MY_WME))))
+    {
+      DBUG_RETURN(TRUE);
+    }
+  }
+  else if (action_flag == CHF_CREATE_FLAG)
+  {
+    if (create_handler_file(path))
+    {
+      my_error(ER_CANT_CREATE_HANDLER_FILE, MYF(0));
+      DBUG_RETURN(1);
+    }
+  }
+
+  /* m_part_info is only NULL when we failed to create a partition table */
+  if (m_part_info)
+  {
+    part= m_part_info->partitions.head();
+    /* part->engine_type may be 0 when we failed to create the partition */
+    if (part->engine_type &&
+        (part->engine_type)->create_partitioning_metadata &&
+        ((part->engine_type)->create_partitioning_metadata)(path, old_path,
+                                                            action_flag))
+    {
+      my_error(ER_CANT_CREATE_HANDLER_FILE, MYF(0));
+      DBUG_RETURN(1);
+    }
+  }
+  DBUG_RETURN(0);
+}
+
+
+/*
+  Create a partitioned table
+
+  SYNOPSIS
+    create()
+    name                              Full path of table name
+    table_arg                         Table object
+    create_info                       Create info generated for CREATE TABLE
+
+  RETURN VALUE
+    >0                        Error
+    0                         Success
+
+  DESCRIPTION
+    create() is called to create a table. The variable name will have the name
+    of the table. When create() is called you do not need to worry about
+    opening the table. Also, the FRM file will have already been created so
+    adjusting create_info will not do you any good. You can overwrite the frm
+    file at this point if you wish to change the table definition, but there
+    are no methods currently provided for doing that.
+
+    Called from handler.cc by ha_create_table().
+*/
+
+int ha_partition::create(const char *name, TABLE *table_arg,
+			 HA_CREATE_INFO *create_info)
+{
+  int error;
+  char name_buff[FN_REFLEN + 1], name_lc_buff[FN_REFLEN];
+  char *name_buffer_ptr;
+  const char *path;
+  uint i;
+  List_iterator_fast <partition_element> part_it(m_part_info->partitions);
+  partition_element *part_elem;
+  handler **file, **abort_file;
+  DBUG_ENTER("ha_partition::create");
+  DBUG_PRINT("enter", ("name: '%s'", name));
+
+  DBUG_ASSERT(!fn_frm_ext(name));
+
+  /* Not allowed to create temporary partitioned tables */
+  if (create_info && create_info->tmp_table())
+  {
+    my_error(ER_FEATURE_NOT_SUPPORTED_WITH_PARTITIONING, MYF(0), "CREATE TEMPORARY TABLE");
+    DBUG_RETURN(TRUE);
+  }
+
+  if (get_from_handler_file(name, ha_thd()->mem_root, false))
+    DBUG_RETURN(TRUE);
+  DBUG_ASSERT(m_file_buffer);
+  name_buffer_ptr= m_name_buffer_ptr;
+  file= m_file;
+  /*
+    Since ha_partition has HA_FILE_BASED, it must alter underlying table names
+    if they do not have HA_FILE_BASED and lower_case_table_names == 2.
+    See Bug#37402, for Mac OS X.
+    The appended #P#<partname>[#SP#<subpartname>] will remain in current case.
+    Using the first partitions handler, since mixing handlers is not allowed.
+  */
+  path= get_canonical_filename(*file, name, name_lc_buff);
+  for (i= 0; i < m_part_info->num_parts; i++)
+  {
+    part_elem= part_it++;
+    if (m_is_sub_partitioned)
+    {
+      uint j;
+      List_iterator_fast <partition_element> sub_it(part_elem->subpartitions);
+      for (j= 0; j < m_part_info->num_subparts; j++)
+      {
+        part_elem= sub_it++;
+        if (unlikely((error= create_partition_name(name_buff,
+                                                   sizeof(name_buff), path,
+                                                   name_buffer_ptr,
+                                                   NORMAL_PART_NAME, FALSE))))
+          goto create_error;
+        if (unlikely((error= set_up_table_before_create(table_arg, name_buff,
+                                                        create_info,
+                                                        part_elem)) ||
+                     ((error= (*file)->ha_create(name_buff, table_arg,
+                                                 create_info)))))
+          goto create_error;
+
+        name_buffer_ptr= strend(name_buffer_ptr) + 1;
+        file++;
+      }
+    }
+    else
+    {
+      if (unlikely((error= create_partition_name(name_buff, sizeof(name_buff),
+                                                 path, name_buffer_ptr,
+                                                 NORMAL_PART_NAME, FALSE))))
+        goto create_error;
+      if (unlikely((error= set_up_table_before_create(table_arg, name_buff,
+                                                      create_info,
+                                                      part_elem)) ||
+                   ((error= (*file)->ha_create(name_buff, table_arg,
+                                               create_info)))))
+        goto create_error;
+
+      name_buffer_ptr= strend(name_buffer_ptr) + 1;
+      file++;
+    }
+  }
+  DBUG_RETURN(0);
+
+create_error:
+  name_buffer_ptr= m_name_buffer_ptr;
+  for (abort_file= file, file= m_file; file < abort_file; file++)
+  {
+    if (!create_partition_name(name_buff, sizeof(name_buff), path,
+                               name_buffer_ptr, NORMAL_PART_NAME, FALSE))
+      (void) (*file)->delete_table((const char*) name_buff);
+    name_buffer_ptr= strend(name_buffer_ptr) + 1;
+  }
+  handler::delete_table(name);
+  DBUG_RETURN(error);
+}
+
+
+/*
+  Drop partitions as part of ALTER TABLE of partitions
+
+  SYNOPSIS
+    drop_partitions()
+    path                        Complete path of db and table name
+
+  RETURN VALUE
+    >0                          Failure
+    0                           Success
+
+  DESCRIPTION
+    Use part_info object on handler object to deduce which partitions to
+    drop (each partition has a state attached to it)
+*/
+
+int ha_partition::drop_partitions(const char *path)
+{
+  List_iterator<partition_element> part_it(m_part_info->partitions);
+  char part_name_buff[FN_REFLEN + 1];
+  uint num_parts= m_part_info->partitions.elements;
+  uint num_subparts= m_part_info->num_subparts;
+  uint i= 0;
+  uint name_variant;
+  int  ret_error;
+  int  error= 0;
+  DBUG_ENTER("ha_partition::drop_partitions");
+
+  /*
+    Assert that it works without HA_FILE_BASED and lower_case_table_name = 2.
+    We use m_file[0] as long as all partitions have the same storage engine.
+  */
+  DBUG_ASSERT(!strcmp(path, get_canonical_filename(m_file[0], path,
+                                                   part_name_buff)));
+  do
+  {
+    partition_element *part_elem= part_it++;
+    if (part_elem->part_state == PART_TO_BE_DROPPED)
+    {
+      handler *file;
+      /*
+        This part is to be dropped, meaning the part or all its subparts.
+      */
+      name_variant= NORMAL_PART_NAME;
+      if (m_is_sub_partitioned)
+      {
+        List_iterator<partition_element> sub_it(part_elem->subpartitions);
+        uint j= 0, part;
+        do
+        {
+          partition_element *sub_elem= sub_it++;
+          part= i * num_subparts + j;
+          if (unlikely((ret_error=
+                        create_subpartition_name(part_name_buff,
+                                                 sizeof(part_name_buff), path,
+                                                 part_elem->partition_name,
+                                                 sub_elem->partition_name,
+                                                 name_variant))))
+            error= ret_error;
+          file= m_file[part];
+          DBUG_PRINT("info", ("Drop subpartition %s", part_name_buff));
+          if (unlikely((ret_error= file->delete_table(part_name_buff))))
+            error= ret_error;
+          if (unlikely(deactivate_ddl_log_entry(sub_elem->log_entry->
+                                                entry_pos)))
+            error= 1;
+        } while (++j < num_subparts);
+      }
+      else
+      {
+        if ((ret_error= create_partition_name(part_name_buff,
+                          sizeof(part_name_buff), path,
+                          part_elem->partition_name, name_variant, TRUE)))
+          error= ret_error;
+        else
+        {
+          file= m_file[i];
+          DBUG_PRINT("info", ("Drop partition %s", part_name_buff));
+          if (unlikely((ret_error= file->delete_table(part_name_buff))))
+            error= ret_error;
+          if (unlikely(deactivate_ddl_log_entry(part_elem->log_entry->
+                                                entry_pos)))
+            error= 1;
+        }
+      }
+      if (part_elem->part_state == PART_IS_CHANGED)
+        part_elem->part_state= PART_NORMAL;
+      else
+        part_elem->part_state= PART_IS_DROPPED;
+    }
+  } while (++i < num_parts);
+  (void) sync_ddl_log();
+  DBUG_RETURN(error);
+}
+
+
+/*
+  Rename partitions as part of ALTER TABLE of partitions
+
+  SYNOPSIS
+    rename_partitions()
+    path                        Complete path of db and table name
+
+  RETURN VALUE
+    TRUE                        Failure
+    FALSE                       Success
+
+  DESCRIPTION
+    When reorganising partitions, adding hash partitions and coalescing
+    partitions it can be necessary to rename partitions while holding
+    an exclusive lock on the table.
+    Which partitions to rename is given by state of partitions found by the
+    partition info struct referenced from the handler object
+*/
+
+int ha_partition::rename_partitions(const char *path)
+{
+  List_iterator<partition_element> part_it(m_part_info->partitions);
+  List_iterator<partition_element> temp_it(m_part_info->temp_partitions);
+  char part_name_buff[FN_REFLEN + 1];
+  char norm_name_buff[FN_REFLEN + 1];
+  uint num_parts= m_part_info->partitions.elements;
+  uint part_count= 0;
+  uint num_subparts= m_part_info->num_subparts;
+  uint i= 0;
+  uint j= 0;
+  int error= 0;
+  int ret_error;
+  uint temp_partitions= m_part_info->temp_partitions.elements;
+  handler *file;
+  partition_element *part_elem, *sub_elem;
+  DBUG_ENTER("ha_partition::rename_partitions");
+
+  /*
+    Assert that it works without HA_FILE_BASED and lower_case_table_name = 2.
+    We use m_file[0] as long as all partitions have the same storage engine.
+  */
+  DBUG_ASSERT(!strcmp(path, get_canonical_filename(m_file[0], path,
+                                                   norm_name_buff)));
+
+  DEBUG_SYNC(ha_thd(), "before_rename_partitions");
+  if (temp_partitions)
+  {
+    /*
+      These are the reorganised partitions that have already been copied.
+      We delete the partitions and log the delete by inactivating the
+      delete log entry in the table log. We only need to synchronise
+      these writes before moving to the next loop since there is no
+      interaction among reorganised partitions, they cannot have the
+      same name.
+    */
+    do
+    {
+      part_elem= temp_it++;
+      if (m_is_sub_partitioned)
+      {
+        List_iterator<partition_element> sub_it(part_elem->subpartitions);
+        j= 0;
+        do
+        {
+          sub_elem= sub_it++;
+          file= m_reorged_file[part_count++];
+          if (unlikely((ret_error=
+                        create_subpartition_name(norm_name_buff,
+                                                 sizeof(norm_name_buff), path,
+                                                 part_elem->partition_name,
+                                                 sub_elem->partition_name,
+                                                 NORMAL_PART_NAME))))
+            error= ret_error;
+          DBUG_PRINT("info", ("Delete subpartition %s", norm_name_buff));
+          if (unlikely((ret_error= file->delete_table(norm_name_buff))))
+            error= ret_error;
+          else if (unlikely(deactivate_ddl_log_entry(sub_elem->log_entry->
+                                                     entry_pos)))
+            error= 1;
+          else
+            sub_elem->log_entry= NULL; /* Indicate success */
+        } while (++j < num_subparts);
+      }
+      else
+      {
+        file= m_reorged_file[part_count++];
+        if (unlikely((ret_error=
+                      create_partition_name(norm_name_buff,
+                                            sizeof(norm_name_buff), path,
+                                            part_elem->partition_name,
+                                            NORMAL_PART_NAME, TRUE))))
+          error= ret_error;
+        else
+        {
+          DBUG_PRINT("info", ("Delete partition %s", norm_name_buff));
+          if (unlikely((ret_error= file->delete_table(norm_name_buff))))
+            error= ret_error;
+          else if (unlikely(deactivate_ddl_log_entry(part_elem->log_entry->
+                                                     entry_pos)))
+            error= 1;
+          else
+            part_elem->log_entry= NULL; /* Indicate success */
+        }
+      }
+    } while (++i < temp_partitions);
+    (void) sync_ddl_log();
+  }
+  i= 0;
+  do
+  {
+    /*
+       When state is PART_IS_CHANGED it means that we have created a new
+       TEMP partition that is to be renamed to normal partition name and
+       we are to delete the old partition with currently the normal name.
+
+       We perform this operation by
+       1) Delete old partition with normal partition name
+       2) Signal this in table log entry
+       3) Synch table log to ensure we have consistency in crashes
+       4) Rename temporary partition name to normal partition name
+       5) Signal this to table log entry
+       It is not necessary to synch the last state since a new rename
+       should not corrupt things if there was no temporary partition.
+
+       The only other parts we need to cater for are new parts that
+       replace reorganised parts. The reorganised parts were deleted
+       by the code above that goes through the temp_partitions list.
+       Thus the synch above makes it safe to simply perform step 4 and 5
+       for those entries.
+    */
+    part_elem= part_it++;
+    if (part_elem->part_state == PART_IS_CHANGED ||
+        part_elem->part_state == PART_TO_BE_DROPPED ||
+        (part_elem->part_state == PART_IS_ADDED && temp_partitions))
+    {
+      if (m_is_sub_partitioned)
+      {
+        List_iterator<partition_element> sub_it(part_elem->subpartitions);
+        uint part;
+
+        j= 0;
+        do
+        {
+          sub_elem= sub_it++;
+          part= i * num_subparts + j;
+          if (unlikely((ret_error=
+                        create_subpartition_name(norm_name_buff,
+                                                 sizeof(norm_name_buff), path,
+                                                 part_elem->partition_name,
+                                                 sub_elem->partition_name,
+                                                 NORMAL_PART_NAME))))
+            error= ret_error;
+          if (part_elem->part_state == PART_IS_CHANGED)
+          {
+            file= m_reorged_file[part_count++];
+            DBUG_PRINT("info", ("Delete subpartition %s", norm_name_buff));
+            if (unlikely((ret_error= file->delete_table(norm_name_buff))))
+              error= ret_error;
+            else if (unlikely(deactivate_ddl_log_entry(sub_elem->log_entry->
+                                                       entry_pos)))
+              error= 1;
+            (void) sync_ddl_log();
+          }
+          file= m_new_file[part];
+          if (unlikely((ret_error=
+                        create_subpartition_name(part_name_buff,
+                                                 sizeof(part_name_buff), path,
+                                                 part_elem->partition_name,
+                                                 sub_elem->partition_name,
+                                                 TEMP_PART_NAME))))
+            error= ret_error;
+          DBUG_PRINT("info", ("Rename subpartition from %s to %s",
+                     part_name_buff, norm_name_buff));
+          if (unlikely((ret_error= file->ha_rename_table(part_name_buff,
+                                                         norm_name_buff))))
+            error= ret_error;
+          else if (unlikely(deactivate_ddl_log_entry(sub_elem->log_entry->
+                                                     entry_pos)))
+            error= 1;
+          else
+            sub_elem->log_entry= NULL;
+        } while (++j < num_subparts);
+      }
+      else
+      {
+        if (unlikely((ret_error=
+                      create_partition_name(norm_name_buff,
+                                            sizeof(norm_name_buff), path,
+                                            part_elem->partition_name,
+                                            NORMAL_PART_NAME, TRUE)) ||
+                     (ret_error= create_partition_name(part_name_buff,
+                                                       sizeof(part_name_buff),
+                                                       path,
+                                                       part_elem->
+                                                       partition_name,
+                                                       TEMP_PART_NAME, TRUE))))
+          error= ret_error;
+        else
+        {
+          if (part_elem->part_state == PART_IS_CHANGED)
+          {
+            file= m_reorged_file[part_count++];
+            DBUG_PRINT("info", ("Delete partition %s", norm_name_buff));
+            if (unlikely((ret_error= file->delete_table(norm_name_buff))))
+              error= ret_error;
+            else if (unlikely(deactivate_ddl_log_entry(part_elem->log_entry->
+                                                       entry_pos)))
+              error= 1;
+            (void) sync_ddl_log();
+          }
+          file= m_new_file[i];
+          DBUG_PRINT("info", ("Rename partition from %s to %s",
+                     part_name_buff, norm_name_buff));
+          if (unlikely((ret_error= file->ha_rename_table(part_name_buff,
+                                                         norm_name_buff))))
+            error= ret_error;
+          else if (unlikely(deactivate_ddl_log_entry(part_elem->log_entry->
+                                                     entry_pos)))
+            error= 1;
+          else
+            part_elem->log_entry= NULL;
+        }
+      }
+    }
+  } while (++i < num_parts);
+  (void) sync_ddl_log();
+  DBUG_RETURN(error);
+}
+
+
+#define OPTIMIZE_PARTS 1
+#define ANALYZE_PARTS 2
+#define CHECK_PARTS   3
+#define REPAIR_PARTS 4
+#define ASSIGN_KEYCACHE_PARTS 5
+#define PRELOAD_KEYS_PARTS 6
+
+static const char *opt_op_name[]= {NULL,
+                                   "optimize", "analyze", "check", "repair",
+                                   "assign_to_keycache", "preload_keys"};
+
+/*
+  Optimize table
+
+  SYNOPSIS
+    optimize()
+    thd               Thread object
+    check_opt         Check/analyze/repair/optimize options
+
+  RETURN VALUES
+    >0                Error
+    0                 Success
+*/
+
+int ha_partition::optimize(THD *thd, HA_CHECK_OPT *check_opt)
+{
+  DBUG_ENTER("ha_partition::optimize");
+
+  DBUG_RETURN(handle_opt_partitions(thd, check_opt, OPTIMIZE_PARTS));
+}
+
+
+/*
+  Analyze table
+
+  SYNOPSIS
+    analyze()
+    thd               Thread object
+    check_opt         Check/analyze/repair/optimize options
+
+  RETURN VALUES
+    >0                Error
+    0                 Success
+*/
+
+int ha_partition::analyze(THD *thd, HA_CHECK_OPT *check_opt)
+{
+  DBUG_ENTER("ha_partition::analyze");
+
+  int result= handle_opt_partitions(thd, check_opt, ANALYZE_PARTS);
+
+  if ((result == 0) && m_file[0]
+      && (m_file[0]->ha_table_flags() & HA_ONLINE_ANALYZE))
+  {
+    /* If this is ANALYZE TABLE that will not force table definition cache
+       eviction, update statistics for the partition handler. */
+    this->info(HA_STATUS_CONST | HA_STATUS_VARIABLE | HA_STATUS_NO_LOCK);
+  }
+
+  DBUG_RETURN(result);
+}
+
+
+/*
+  Check table
+
+  SYNOPSIS
+    check()
+    thd               Thread object
+    check_opt         Check/analyze/repair/optimize options
+
+  RETURN VALUES
+    >0                Error
+    0                 Success
+*/
+
+int ha_partition::check(THD *thd, HA_CHECK_OPT *check_opt)
+{
+  DBUG_ENTER("ha_partition::check");
+
+  DBUG_RETURN(handle_opt_partitions(thd, check_opt, CHECK_PARTS));
+}
+
+
+/*
+  Repair table
+
+  SYNOPSIS
+    repair()
+    thd               Thread object
+    check_opt         Check/analyze/repair/optimize options
+
+  RETURN VALUES
+    >0                Error
+    0                 Success
+*/
+
+int ha_partition::repair(THD *thd, HA_CHECK_OPT *check_opt)
+{
+  DBUG_ENTER("ha_partition::repair");
+
+  int res= handle_opt_partitions(thd, check_opt, REPAIR_PARTS);
+  DBUG_RETURN(res);
+}
+
+/**
+  Assign to keycache
+
+  @param thd          Thread object
+  @param check_opt    Check/analyze/repair/optimize options
+
+  @return
+    @retval >0        Error
+    @retval 0         Success
+*/
+
+int ha_partition::assign_to_keycache(THD *thd, HA_CHECK_OPT *check_opt)
+{
+  DBUG_ENTER("ha_partition::assign_to_keycache");
+
+  DBUG_RETURN(handle_opt_partitions(thd, check_opt, ASSIGN_KEYCACHE_PARTS));
+}
+
+
+/**
+  Preload to keycache
+
+  @param thd          Thread object
+  @param check_opt    Check/analyze/repair/optimize options
+
+  @return
+    @retval >0        Error
+    @retval 0         Success
+*/
+
+int ha_partition::preload_keys(THD *thd, HA_CHECK_OPT *check_opt)
+{
+  DBUG_ENTER("ha_partition::preload_keys");
+
+  DBUG_RETURN(handle_opt_partitions(thd, check_opt, PRELOAD_KEYS_PARTS));
+}
+
+
+/*
+  Handle optimize/analyze/check/repair of one partition
+
+  SYNOPSIS
+    handle_opt_part()
+    thd                      Thread object
+    check_opt                Options
+    file                     Handler object of partition
+    flag                     Optimize/Analyze/Check/Repair flag
+
+  RETURN VALUE
+    >0                        Failure
+    0                         Success
+*/
+
+int ha_partition::handle_opt_part(THD *thd, HA_CHECK_OPT *check_opt,
+                                  uint part_id, uint flag)
+{
+  int error;
+  handler *file= m_file[part_id];
+  DBUG_ENTER("handle_opt_part");
+  DBUG_PRINT("enter", ("flag: %u", flag));
+
+  if (flag == OPTIMIZE_PARTS)
+    error= file->ha_optimize(thd, check_opt);
+  else if (flag == ANALYZE_PARTS)
+    error= file->ha_analyze(thd, check_opt);
+  else if (flag == CHECK_PARTS)
+  {
+    error= file->ha_check(thd, check_opt);
+    if (!error ||
+        error == HA_ADMIN_ALREADY_DONE ||
+        error == HA_ADMIN_NOT_IMPLEMENTED)
+    {
+      if (check_opt->flags & (T_MEDIUM | T_EXTEND))
+        error= check_misplaced_rows(part_id, false);
+    }
+  }
+  else if (flag == REPAIR_PARTS)
+  {
+    error= file->ha_repair(thd, check_opt);
+    if (!error ||
+        error == HA_ADMIN_ALREADY_DONE ||
+        error == HA_ADMIN_NOT_IMPLEMENTED)
+    {
+      if (check_opt->flags & (T_MEDIUM | T_EXTEND))
+        error= check_misplaced_rows(part_id, true);
+    }
+  }
+  else if (flag == ASSIGN_KEYCACHE_PARTS)
+    error= file->assign_to_keycache(thd, check_opt);
+  else if (flag == PRELOAD_KEYS_PARTS)
+    error= file->preload_keys(thd, check_opt);
+  else
+  {
+    DBUG_ASSERT(FALSE);
+    error= 1;
+  }
+  if (error == HA_ADMIN_ALREADY_DONE)
+    error= 0;
+  DBUG_RETURN(error);
+}
+
+
+/*
+   print a message row formatted for ANALYZE/CHECK/OPTIMIZE/REPAIR TABLE
+   (modelled after mi_check_print_msg)
+   TODO: move this into the handler, or rewrite mysql_admin_table.
+*/
+bool print_admin_msg(THD* thd, uint len,
+                            const char* msg_type,
+                            const char* db_name, String &table_name,
+                            const char* op_name, const char *fmt, ...)
+  ATTRIBUTE_FORMAT(printf, 7, 8);
+bool print_admin_msg(THD* thd, uint len,
+                            const char* msg_type,
+                            const char* db_name, String &table_name,
+                            const char* op_name, const char *fmt, ...)
+{
+  va_list args;
+  Protocol *protocol= thd->protocol;
+  size_t length;
+  size_t msg_length;
+  char name[NAME_LEN*2+2];
+  char *msgbuf;
+  bool error= true;
+
+  if (!(msgbuf= (char*) my_malloc(key_memory_Partition_admin, len, MYF(0))))
+    return true;
+  va_start(args, fmt);
+  msg_length= my_vsnprintf(msgbuf, len, fmt, args);
+  va_end(args);
+  if (msg_length >= (len - 1))
+    goto err;
+  msgbuf[len - 1]= 0; // healthy paranoia
+
+
+  if (!thd->vio_ok())
+  {
+    sql_print_error("%s", msgbuf);
+    goto err;
+  }
+
+  length=(size_t)(strxmov(name, db_name, ".", table_name.c_ptr_safe(), NullS) - name);
+  /*
+     TODO: switch from protocol to push_warning here. The main reason we didn't
+     it yet is parallel repair, which threads have no THD object accessible via
+     current_thd.
+
+     Also we likely need to lock mutex here (in both cases with protocol and
+     push_warning).
+  */
+  DBUG_PRINT("info",("print_admin_msg:  %s, %s, %s, %s", name, op_name,
+                     msg_type, msgbuf));
+  protocol->prepare_for_resend();
+  protocol->store(name, length, system_charset_info);
+  protocol->store(op_name, system_charset_info);
+  protocol->store(msg_type, system_charset_info);
+  protocol->store(msgbuf, msg_length, system_charset_info);
+  if (protocol->write())
+  {
+    sql_print_error("Failed on my_net_write, writing to stderr instead: %s",
+                    msgbuf);
+    goto err;
+  }
+  error= false;
+err:
+  my_free(msgbuf);
+  return error;
+}
+
+
+/*
+  Handle optimize/analyze/check/repair of partitions
+
+  SYNOPSIS
+    handle_opt_partitions()
+    thd                      Thread object
+    check_opt                Options
+    flag                     Optimize/Analyze/Check/Repair flag
+
+  RETURN VALUE
+    >0                        Failure
+    0                         Success
+*/
+
+int ha_partition::handle_opt_partitions(THD *thd, HA_CHECK_OPT *check_opt,
+                                        uint flag)
+{
+  List_iterator<partition_element> part_it(m_part_info->partitions);
+  uint num_parts= m_part_info->num_parts;
+  uint num_subparts= m_part_info->num_subparts;
+  uint i= 0;
+  int error;
+  DBUG_ENTER("ha_partition::handle_opt_partitions");
+  DBUG_PRINT("enter", ("flag= %u", flag));
+
+  do
+  {
+    partition_element *part_elem= part_it++;
+    /*
+      when ALTER TABLE <CMD> PARTITION ...
+      it should only do named partitions, otherwise all partitions
+    */
+    if (!(thd->lex->alter_info.partition_flags & ALTER_PARTITION_ADMIN) ||
+        part_elem->part_state == PART_ADMIN)
+    {
+      if (m_is_sub_partitioned)
+      {
+        List_iterator<partition_element> subpart_it(part_elem->subpartitions);
+        partition_element *sub_elem;
+        uint j= 0, part;
+        do
+        {
+          sub_elem= subpart_it++;
+          part= i * num_subparts + j;
+          DBUG_PRINT("info", ("Optimize subpartition %u (%s)",
+                     part, sub_elem->partition_name));
+          if (unlikely((error= handle_opt_part(thd, check_opt, part, flag))))
+          {
+            /* print a line which partition the error belongs to */
+            if (error != HA_ADMIN_NOT_IMPLEMENTED &&
+                error != HA_ADMIN_ALREADY_DONE &&
+                error != HA_ADMIN_TRY_ALTER)
+            {
+	      print_admin_msg(thd, MYSQL_ERRMSG_SIZE, "error",
+                              table_share->db.str, table->alias,
+                              opt_op_name[flag],
+                              "Subpartition %s returned error",
+                              sub_elem->partition_name);
+            }
+            /* reset part_state for the remaining partitions */
+            do
+            {
+              if (part_elem->part_state == PART_ADMIN)
+                part_elem->part_state= PART_NORMAL;
+            } while ((part_elem= part_it++));
+            DBUG_RETURN(error);
+          }
+        } while (++j < num_subparts);
+      }
+      else
+      {
+        DBUG_PRINT("info", ("Optimize partition %u (%s)", i,
+                            part_elem->partition_name));
+        if (unlikely((error= handle_opt_part(thd, check_opt, i, flag))))
+        {
+          /* print a line which partition the error belongs to */
+          if (error != HA_ADMIN_NOT_IMPLEMENTED &&
+              error != HA_ADMIN_ALREADY_DONE &&
+              error != HA_ADMIN_TRY_ALTER)
+          {
+	    print_admin_msg(thd, MYSQL_ERRMSG_SIZE, "error",
+                            table_share->db.str, table->alias,
+                            opt_op_name[flag], "Partition %s returned error",
+                            part_elem->partition_name);
+          }
+          /* reset part_state for the remaining partitions */
+          do
+          {
+            if (part_elem->part_state == PART_ADMIN)
+              part_elem->part_state= PART_NORMAL;
+          } while ((part_elem= part_it++));
+          DBUG_RETURN(error);
+        }
+      }
+      part_elem->part_state= PART_NORMAL;
+    }
+  } while (++i < num_parts);
+  DBUG_RETURN(FALSE);
+}
+
+
+/**
+  @brief Check and repair the table if necessary
+
+  @param thd    Thread object
+
+  @retval TRUE  Error/Not supported
+  @retval FALSE Success
+
+  @note Called if open_table_from_share fails and ::is_crashed().
+*/
+
+bool ha_partition::check_and_repair(THD *thd)
+{
+  handler **file= m_file;
+  DBUG_ENTER("ha_partition::check_and_repair");
+
+  do
+  {
+    if ((*file)->ha_check_and_repair(thd))
+      DBUG_RETURN(TRUE);
+  } while (*(++file));
+  DBUG_RETURN(FALSE);
+}
+
+
+/**
+  @breif Check if the table can be automatically repaired
+
+  @retval TRUE  Can be auto repaired
+  @retval FALSE Cannot be auto repaired
+*/
+
+bool ha_partition::auto_repair(int error) const
+{
+  DBUG_ENTER("ha_partition::auto_repair");
+
+  /*
+    As long as we only support one storage engine per table,
+    we can use the first partition for this function.
+  */
+  DBUG_RETURN(m_file[0]->auto_repair(error));
+}
+
+
+/**
+  @breif Check if the table is crashed
+
+  @retval TRUE  Crashed
+  @retval FALSE Not crashed
+*/
+
+bool ha_partition::is_crashed() const
+{
+  handler **file= m_file;
+  DBUG_ENTER("ha_partition::is_crashed");
+
+  do
+  {
+    if ((*file)->is_crashed())
+      DBUG_RETURN(TRUE);
+  } while (*(++file));
+  DBUG_RETURN(FALSE);
+}
+
+
+/*
+  Prepare by creating a new partition
+
+  SYNOPSIS
+    prepare_new_partition()
+    table                      Table object
+    create_info                Create info from CREATE TABLE
+    file                       Handler object of new partition
+    part_name                  partition name
+
+  RETURN VALUE
+    >0                         Error
+    0                          Success
+*/
+
+int ha_partition::prepare_new_partition(TABLE *tbl,
+                                        HA_CREATE_INFO *create_info,
+                                        handler *file, const char *part_name,
+                                        partition_element *p_elem,
+                                        uint disable_non_uniq_indexes)
+{
+  int error;
+  DBUG_ENTER("prepare_new_partition");
+
+  /*
+    This call to set_up_table_before_create() is done for an alter table.
+    So this may be the second time around for this partition_element,
+    depending on how many partitions and subpartitions there were before,
+    and how many there are now.
+    The first time, on the CREATE, data_file_name and index_file_name
+    came from the parser.  They did not have the file name attached to
+    the end.  But if this partition is less than the total number of
+    previous partitions, it's data_file_name has the filename attached.
+    So we need to take the partition filename off if it exists.
+    That file name may be different from part_name, which will be
+    attached in append_file_to_dir().
+  */
+  truncate_partition_filename((char*) p_elem->data_file_name);
+  truncate_partition_filename((char*) p_elem->index_file_name);
+
+  if (unlikely((error= set_up_table_before_create(tbl, part_name, create_info,
+                                                  p_elem))))
+    goto error_create;
+
+  if (!(file->ht->flags & HTON_CAN_READ_CONNECT_STRING_IN_PARTITION))
+    tbl->s->connect_string= p_elem->connect_string;
+  create_info->options|= HA_CREATE_TMP_ALTER;
+  if ((error= file->ha_create(part_name, tbl, create_info)))
+  {
+    /*
+      Added for safety, InnoDB reports HA_ERR_FOUND_DUPP_KEY
+      if the table/partition already exists.
+      If we return that error code, then print_error would try to
+      get_dup_key on a non-existing partition.
+      So return a more reasonable error code.
+    */
+    if (error == HA_ERR_FOUND_DUPP_KEY)
+      error= HA_ERR_TABLE_EXIST;
+    goto error_create;
+  }
+  DBUG_PRINT("info", ("partition %s created", part_name));
+  if (unlikely((error= file->ha_open(tbl, part_name, m_mode,
+                                     m_open_test_lock | HA_OPEN_NO_PSI_CALL |
+                                     HA_OPEN_FOR_CREATE))))
+    goto error_open;
+  DBUG_PRINT("info", ("partition %s opened", part_name));
+
+  /*
+    Note: if you plan to add another call that may return failure,
+    better to do it before external_lock() as cleanup_new_partition()
+    assumes that external_lock() is last call that may fail here.
+    Otherwise see description for cleanup_new_partition().
+  */
+  if (unlikely((error= file->ha_external_lock(ha_thd(), F_WRLCK))))
+    goto error_external_lock;
+  DBUG_PRINT("info", ("partition %s external locked", part_name));
+
+  if (disable_non_uniq_indexes)
+    file->ha_disable_indexes(HA_KEY_SWITCH_NONUNIQ_SAVE);
+
+  DBUG_RETURN(0);
+error_external_lock:
+  (void) file->ha_close();
+error_open:
+  (void) file->delete_table(part_name);
+error_create:
+  DBUG_RETURN(error);
+}
+
+
+/*
+  Cleanup by removing all created partitions after error
+
+  SYNOPSIS
+    cleanup_new_partition()
+    part_count             Number of partitions to remove
+
+  RETURN VALUE
+    NONE
+
+  DESCRIPTION
+    This function is called immediately after prepare_new_partition() in
+    case the latter fails.
+
+    In prepare_new_partition() last call that may return failure is
+    external_lock(). That means if prepare_new_partition() fails,
+    partition does not have external lock. Thus no need to call
+    external_lock(F_UNLCK) here.
+
+  TODO:
+    We must ensure that in the case that we get an error during the process
+    that we call external_lock with F_UNLCK, close the table and delete the
+    table in the case where we have been successful with prepare_handler.
+    We solve this by keeping an array of successful calls to prepare_handler
+    which can then be used to undo the call.
+*/
+
+void ha_partition::cleanup_new_partition(uint part_count)
+{
+  DBUG_ENTER("ha_partition::cleanup_new_partition");
+
+  if (m_added_file)
+  {
+    THD *thd= ha_thd();
+    handler **file= m_added_file;
+    while ((part_count > 0) && (*file))
+    {
+      (*file)->ha_external_unlock(thd);
+      (*file)->ha_close();
+
+      /* Leave the (*file)->delete_table(part_name) to the ddl-log */
+
+      file++;
+      part_count--;
+    }
+    m_added_file= NULL;
+  }
+  DBUG_VOID_RETURN;
+}
+
+/*
+  Implement the partition changes defined by ALTER TABLE of partitions
+
+  SYNOPSIS
+    change_partitions()
+    create_info                 HA_CREATE_INFO object describing all
+                                fields and indexes in table
+    path                        Complete path of db and table name
+    out: copied                 Output parameter where number of copied
+                                records are added
+    out: deleted                Output parameter where number of deleted
+                                records are added
+    pack_frm_data               Reference to packed frm file
+    pack_frm_len                Length of packed frm file
+
+  RETURN VALUE
+    >0                        Failure
+    0                         Success
+
+  DESCRIPTION
+    Add and copy if needed a number of partitions, during this operation
+    no other operation is ongoing in the server. This is used by
+    ADD PARTITION all types as well as by REORGANIZE PARTITION. For
+    one-phased implementations it is used also by DROP and COALESCE
+    PARTITIONs.
+    One-phased implementation needs the new frm file, other handlers will
+    get zero length and a NULL reference here.
+*/
+
+int ha_partition::change_partitions(HA_CREATE_INFO *create_info,
+                                    const char *path,
+                                    ulonglong * const copied,
+                                    ulonglong * const deleted,
+                                    const uchar *pack_frm_data
+                                    __attribute__((unused)),
+                                    size_t pack_frm_len
+                                    __attribute__((unused)))
+{
+  List_iterator<partition_element> part_it(m_part_info->partitions);
+  List_iterator <partition_element> t_it(m_part_info->temp_partitions);
+  char part_name_buff[FN_REFLEN + 1];
+  uint num_parts= m_part_info->partitions.elements;
+  uint num_subparts= m_part_info->num_subparts;
+  uint i= 0;
+  uint num_remain_partitions, part_count, orig_count;
+  handler **new_file_array;
+  int error= 1;
+  bool first;
+  uint temp_partitions= m_part_info->temp_partitions.elements;
+  THD *thd= ha_thd();
+  DBUG_ENTER("ha_partition::change_partitions");
+
+  /*
+    Assert that it works without HA_FILE_BASED and lower_case_table_name = 2.
+    We use m_file[0] as long as all partitions have the same storage engine.
+  */
+  DBUG_ASSERT(!strcmp(path, get_canonical_filename(m_file[0], path,
+                                                   part_name_buff)));
+  m_reorged_parts= 0;
+  if (!m_part_info->is_sub_partitioned())
+    num_subparts= 1;
+
+  /*
+    Step 1:
+      Calculate number of reorganised partitions and allocate space for
+      their handler references.
+  */
+  if (temp_partitions)
+  {
+    m_reorged_parts= temp_partitions * num_subparts;
+  }
+  else
+  {
+    do
+    {
+      partition_element *part_elem= part_it++;
+      if (part_elem->part_state == PART_CHANGED ||
+          part_elem->part_state == PART_REORGED_DROPPED)
+      {
+        m_reorged_parts+= num_subparts;
+      }
+    } while (++i < num_parts);
+  }
+  if (m_reorged_parts &&
+      !(m_reorged_file= (handler**) thd->calloc(sizeof(handler*)*
+                                                (m_reorged_parts + 1))))
+  {
+    DBUG_RETURN(HA_ERR_OUT_OF_MEM);
+  }
+
+  /*
+    Step 2:
+      Calculate number of partitions after change and allocate space for
+      their handler references.
+  */
+  num_remain_partitions= 0;
+  if (temp_partitions)
+  {
+    num_remain_partitions= num_parts * num_subparts;
+  }
+  else
+  {
+    part_it.rewind();
+    i= 0;
+    do
+    {
+      partition_element *part_elem= part_it++;
+      if (part_elem->part_state == PART_NORMAL ||
+          part_elem->part_state == PART_TO_BE_ADDED ||
+          part_elem->part_state == PART_CHANGED)
+      {
+        num_remain_partitions+= num_subparts;
+      }
+    } while (++i < num_parts);
+  }
+  if (!(new_file_array= ((handler**)
+                         thd->calloc(sizeof(handler*)*
+                                     (2*(num_remain_partitions + 1))))))
+  {
+    DBUG_RETURN(HA_ERR_OUT_OF_MEM);
+  }
+  m_added_file= &new_file_array[num_remain_partitions + 1];
+
+  /*
+    Step 3:
+      Fill m_reorged_file with handler references and NULL at the end
+  */
+  if (m_reorged_parts)
+  {
+    i= 0;
+    part_count= 0;
+    first= TRUE;
+    part_it.rewind();
+    do
+    {
+      partition_element *part_elem= part_it++;
+      if (part_elem->part_state == PART_CHANGED ||
+          part_elem->part_state == PART_REORGED_DROPPED)
+      {
+        memcpy((void*)&m_reorged_file[part_count],
+               (void*)&m_file[i*num_subparts],
+               sizeof(handler*)*num_subparts);
+        part_count+= num_subparts;
+      }
+      else if (first && temp_partitions &&
+               part_elem->part_state == PART_TO_BE_ADDED)
+      {
+        /*
+          When doing an ALTER TABLE REORGANIZE PARTITION a number of
+          partitions is to be reorganised into a set of new partitions.
+          The reorganised partitions are in this case in the temp_partitions
+          list. We copy all of them in one batch and thus we only do this
+          until we find the first partition with state PART_TO_BE_ADDED
+          since this is where the new partitions go in and where the old
+          ones used to be.
+        */
+        first= FALSE;
+        DBUG_ASSERT(((i*num_subparts) + m_reorged_parts) <= m_file_tot_parts);
+        memcpy((void*)m_reorged_file, &m_file[i*num_subparts],
+               sizeof(handler*)*m_reorged_parts);
+      }
+    } while (++i < num_parts);
+  }
+
+  /*
+    Step 4:
+      Fill new_array_file with handler references. Create the handlers if
+      needed.
+  */
+  i= 0;
+  part_count= 0;
+  orig_count= 0;
+  first= TRUE;
+  part_it.rewind();
+  do
+  {
+    partition_element *part_elem= part_it++;
+    if (part_elem->part_state == PART_NORMAL)
+    {
+      DBUG_ASSERT(orig_count + num_subparts <= m_file_tot_parts);
+      memcpy((void*)&new_file_array[part_count], (void*)&m_file[orig_count],
+             sizeof(handler*)*num_subparts);
+      part_count+= num_subparts;
+      orig_count+= num_subparts;
+    }
+    else if (part_elem->part_state == PART_CHANGED ||
+             part_elem->part_state == PART_TO_BE_ADDED)
+    {
+      uint j= 0;
+      Parts_share_refs *p_share_refs;
+      /*
+        The Handler_shares for each partition's handler can be allocated
+        within this handler, since there will not be any more instances of the
+        new partitions, until the table is reopened after the ALTER succeeded.
+      */
+      p_share_refs= new Parts_share_refs;
+      if (!p_share_refs)
+        DBUG_RETURN(HA_ERR_OUT_OF_MEM);
+      if (p_share_refs->init(num_subparts))
+        DBUG_RETURN(HA_ERR_OUT_OF_MEM);
+      if (m_new_partitions_share_refs.push_back(p_share_refs, thd->mem_root))
+        DBUG_RETURN(HA_ERR_OUT_OF_MEM);
+      do
+      {
+        handler **new_file= &new_file_array[part_count++];
+        if (!(*new_file=
+              get_new_handler(table->s,
+                              thd->mem_root,
+                              part_elem->engine_type)))
+        {
+          DBUG_RETURN(HA_ERR_OUT_OF_MEM);
+        }
+        if ((*new_file)->set_ha_share_ref(&p_share_refs->ha_shares[j]))
+        {
+          DBUG_RETURN(HA_ERR_OUT_OF_MEM);
+        }
+      } while (++j < num_subparts);
+      if (part_elem->part_state == PART_CHANGED)
+        orig_count+= num_subparts;
+      else if (temp_partitions && first)
+      {
+        orig_count+= (num_subparts * temp_partitions);
+        first= FALSE;
+      }
+    }
+  } while (++i < num_parts);
+  first= FALSE;
+  /*
+    Step 5:
+      Create the new partitions and also open, lock and call external_lock
+      on them to prepare them for copy phase and also for later close
+      calls
+  */
+
+  /*
+     Before creating new partitions check whether indexes are disabled
+     in the  partitions.
+  */
+
+  uint disable_non_uniq_indexes= indexes_are_disabled();
+
+  i= 0;
+  part_count= 0;
+  part_it.rewind();
+  do
+  {
+    partition_element *part_elem= part_it++;
+    if (part_elem->part_state == PART_TO_BE_ADDED ||
+        part_elem->part_state == PART_CHANGED)
+    {
+      /*
+        A new partition needs to be created PART_TO_BE_ADDED means an
+        entirely new partition and PART_CHANGED means a changed partition
+        that will still exist with either more or less data in it.
+      */
+      uint name_variant= NORMAL_PART_NAME;
+      if (part_elem->part_state == PART_CHANGED ||
+          (part_elem->part_state == PART_TO_BE_ADDED && temp_partitions))
+        name_variant= TEMP_PART_NAME;
+      if (m_part_info->is_sub_partitioned())
+      {
+        List_iterator<partition_element> sub_it(part_elem->subpartitions);
+        uint j= 0, part;
+        do
+        {
+          partition_element *sub_elem= sub_it++;
+          if (unlikely((error=
+                        create_subpartition_name(part_name_buff,
+                                                 sizeof(part_name_buff), path,
+                                                 part_elem->partition_name,
+                                                 sub_elem->partition_name,
+                                                 name_variant))))
+          {
+            cleanup_new_partition(part_count);
+            DBUG_RETURN(error);
+          }
+          part= i * num_subparts + j;
+          DBUG_PRINT("info", ("Add subpartition %s", part_name_buff));
+          if (unlikely((error=
+                        prepare_new_partition(table, create_info,
+                                              new_file_array[part],
+                                              (const char *)part_name_buff,
+                                              sub_elem,
+                                              disable_non_uniq_indexes))))
+          {
+            cleanup_new_partition(part_count);
+            DBUG_RETURN(error);
+          }
+
+          m_added_file[part_count++]= new_file_array[part];
+        } while (++j < num_subparts);
+      }
+      else
+      {
+        if (unlikely((error=
+                      create_partition_name(part_name_buff,
+                                            sizeof(part_name_buff), path,
+                                            part_elem->partition_name,
+                                            name_variant, TRUE))))
+        {
+          cleanup_new_partition(part_count);
+          DBUG_RETURN(error);
+        }
+
+        DBUG_PRINT("info", ("Add partition %s", part_name_buff));
+        if (unlikely((error=
+                      prepare_new_partition(table, create_info,
+                                            new_file_array[i],
+                                            (const char *)part_name_buff,
+                                            part_elem,
+                                            disable_non_uniq_indexes))))
+        {
+          cleanup_new_partition(part_count);
+          DBUG_RETURN(error);
+        }
+
+        m_added_file[part_count++]= new_file_array[i];
+      }
+    }
+  } while (++i < num_parts);
+
+  /*
+    Step 6:
+      State update to prepare for next write of the frm file.
+  */
+  i= 0;
+  part_it.rewind();
+  do
+  {
+    partition_element *part_elem= part_it++;
+    if (part_elem->part_state == PART_TO_BE_ADDED)
+      part_elem->part_state= PART_IS_ADDED;
+    else if (part_elem->part_state == PART_CHANGED)
+      part_elem->part_state= PART_IS_CHANGED;
+    else if (part_elem->part_state == PART_REORGED_DROPPED)
+      part_elem->part_state= PART_TO_BE_DROPPED;
+  } while (++i < num_parts);
+  for (i= 0; i < temp_partitions; i++)
+  {
+    partition_element *part_elem= t_it++;
+    DBUG_ASSERT(part_elem->part_state == PART_TO_BE_REORGED);
+    part_elem->part_state= PART_TO_BE_DROPPED;
+  }
+  DBUG_ASSERT(m_new_file == 0);
+  m_new_file= new_file_array;
+  if (unlikely((error= copy_partitions(copied, deleted))))
+  {
+    /*
+      Close and unlock the new temporary partitions.
+      They will later be deleted through the ddl-log.
+    */
+    cleanup_new_partition(part_count);
+    m_new_file= 0;
+  }
+  DBUG_RETURN(error);
+}
+
+
+/*
+  Copy partitions as part of ALTER TABLE of partitions
+
+  SYNOPSIS
+    copy_partitions()
+    out:copied                 Number of records copied
+    out:deleted                Number of records deleted
+
+  RETURN VALUE
+    >0                         Error code
+    0                          Success
+
+  DESCRIPTION
+    change_partitions has done all the preparations, now it is time to
+    actually copy the data from the reorganised partitions to the new
+    partitions.
+*/
+
+int ha_partition::copy_partitions(ulonglong * const copied,
+                                  ulonglong * const deleted)
+{
+  uint reorg_part= 0;
+  int result= 0;
+  longlong func_value;
+  DBUG_ENTER("ha_partition::copy_partitions");
+
+  if (m_part_info->linear_hash_ind)
+  {
+    if (m_part_info->part_type == HASH_PARTITION)
+      set_linear_hash_mask(m_part_info, m_part_info->num_parts);
+    else
+      set_linear_hash_mask(m_part_info, m_part_info->num_subparts);
+  }
+  else if (m_part_info->part_type == VERSIONING_PARTITION)
+  {
+    if (m_part_info->check_constants(ha_thd(), m_part_info))
+      goto init_error;
+  }
+
+  while (reorg_part < m_reorged_parts)
+  {
+    handler *file= m_reorged_file[reorg_part];
+    uint32 new_part;
+
+    late_extra_cache(reorg_part);
+    if (unlikely((result= file->ha_rnd_init_with_error(1))))
+      goto init_error;
+    while (TRUE)
+    {
+      if ((result= file->ha_rnd_next(m_rec0)))
+      {
+        if (result != HA_ERR_END_OF_FILE)
+          goto error;
+        /*
+          End-of-file reached, break out to continue with next partition or
+          end the copy process.
+        */
+        break;
+      }
+      /* Found record to insert into new handler */
+      if (m_part_info->get_partition_id(m_part_info, &new_part,
+                                        &func_value))
+      {
+        /*
+           This record is in the original table but will not be in the new
+           table since it doesn't fit into any partition any longer due to
+           changed partitioning ranges or list values.
+        */
+        (*deleted)++;
+      }
+      else
+      {
+        /* Copy record to new handler */
+        (*copied)++;
+        DBUG_ASSERT(!m_new_file[new_part]->row_logging);
+        result= m_new_file[new_part]->ha_write_row(m_rec0);
+        if (result)
+          goto error;
+      }
+    }
+    late_extra_no_cache(reorg_part);
+    file->ha_rnd_end();
+    reorg_part++;
+  }
+  DBUG_EXECUTE_IF("debug_abort_copy_partitions",
+                  DBUG_RETURN(HA_ERR_UNSUPPORTED); );
+  DBUG_RETURN(FALSE);
+error:
+  m_reorged_file[reorg_part]->ha_rnd_end();
+init_error:
+  DBUG_RETURN(result);
+}
+
+/*
+  Update create info as part of ALTER TABLE
+
+  SYNOPSIS
+    update_create_info()
+    create_info                   Create info from ALTER TABLE
+
+  RETURN VALUE
+    NONE
+
+  DESCRIPTION
+  Forward this handler call to the storage engine foreach
+  partition handler.  The data_file_name for each partition may
+  need to be reset if the tablespace was moved.  Use a dummy
+  HA_CREATE_INFO structure and transfer necessary data.
+*/
+
+void ha_partition::update_create_info(HA_CREATE_INFO *create_info)
+{
+  DBUG_ENTER("ha_partition::update_create_info");
+
+  /*
+    Fix for bug#38751, some engines needs info-calls in ALTER.
+    Archive need this since it flushes in ::info.
+    HA_STATUS_AUTO is optimized so it will not always be forwarded
+    to all partitions, but HA_STATUS_VARIABLE will.
+  */
+  info(HA_STATUS_VARIABLE | HA_STATUS_OPEN);
+
+  info(HA_STATUS_AUTO);
+
+  if (!(create_info->used_fields & HA_CREATE_USED_AUTO))
+    create_info->auto_increment_value= stats.auto_increment_value;
+
+  /*
+    DATA DIRECTORY and INDEX DIRECTORY are never applied to the whole
+    partitioned table, only its parts.
+  */
+  my_bool from_alter= (create_info->data_file_name == (const char*) -1);
+  create_info->data_file_name= create_info->index_file_name= NULL;
+
+  if (!(m_file[0]->ht->flags & HTON_CAN_READ_CONNECT_STRING_IN_PARTITION))
+    create_info->connect_string= null_clex_str;
+
+  /*
+    We do not need to update the individual partition DATA DIRECTORY settings
+    since they can be changed by ALTER TABLE ... REORGANIZE PARTITIONS.
+  */
+  if (from_alter)
+    DBUG_VOID_RETURN;
+
+  /*
+    send Handler::update_create_info() to the storage engine for each
+    partition that currently has a handler object.  Using a dummy
+    HA_CREATE_INFO structure to collect DATA and INDEX DIRECTORYs.
+  */
+
+  List_iterator<partition_element> part_it(m_part_info->partitions);
+  partition_element *part_elem, *sub_elem;
+  uint num_subparts= m_part_info->num_subparts;
+  uint num_parts= (num_subparts ? m_file_tot_parts / num_subparts :
+                   m_file_tot_parts);
+  HA_CREATE_INFO dummy_info;
+  dummy_info.init();
+
+  /*
+    Since update_create_info() can be called from mysql_prepare_alter_table()
+    when not all handlers are set up, we look for that condition first.
+    If all handlers are not available, do not call update_create_info for any.
+  */
+  uint i, j, part;
+  for (i= 0; i < num_parts; i++)
+  {
+    part_elem= part_it++;
+    if (!part_elem)
+      DBUG_VOID_RETURN;
+    if (m_is_sub_partitioned)
+    {
+      List_iterator<partition_element> subpart_it(part_elem->subpartitions);
+      for (j= 0; j < num_subparts; j++)
+      {
+        sub_elem= subpart_it++;
+        if (!sub_elem)
+          DBUG_VOID_RETURN;
+        part= i * num_subparts + j;
+        if (part >= m_file_tot_parts || !m_file[part])
+          DBUG_VOID_RETURN;
+      }
+    }
+    else
+    {
+      if (!m_file[i])
+        DBUG_VOID_RETURN;
+    }
+  }
+  part_it.rewind();
+
+  for (i= 0; i < num_parts; i++)
+  {
+    part_elem= part_it++;
+    DBUG_ASSERT(part_elem);
+    if (m_is_sub_partitioned)
+    {
+      List_iterator<partition_element> subpart_it(part_elem->subpartitions);
+      for (j= 0; j < num_subparts; j++)
+      {
+        sub_elem= subpart_it++;
+        DBUG_ASSERT(sub_elem);
+        part= i * num_subparts + j;
+        DBUG_ASSERT(part < m_file_tot_parts);
+        DBUG_ASSERT(m_file[part]);
+        dummy_info.data_file_name= dummy_info.index_file_name = NULL;
+        m_file[part]->update_create_info(&dummy_info);
+        sub_elem->data_file_name = (char*) dummy_info.data_file_name;
+        sub_elem->index_file_name = (char*) dummy_info.index_file_name;
+      }
+    }
+    else
+    {
+      DBUG_ASSERT(m_file[i]);
+      dummy_info.data_file_name= dummy_info.index_file_name= NULL;
+      m_file[i]->update_create_info(&dummy_info);
+      part_elem->data_file_name = (char*) dummy_info.data_file_name;
+      part_elem->index_file_name = (char*) dummy_info.index_file_name;
+    }
+  }
+  DBUG_VOID_RETURN;
+}
+
+
+/**
+  Change the internal TABLE_SHARE pointer
+
+  @param table_arg    TABLE object
+  @param share        New share to use
+
+  @note Is used in error handling in delete_table.
+  All handlers should exist (lock_partitions should not be used)
+*/
+
+void ha_partition::change_table_ptr(TABLE *table_arg, TABLE_SHARE *share)
+{
+  handler **file_array;
+  table= table_arg;
+  table_share= share;
+  /*
+    m_file can be NULL when using an old cached table in DROP TABLE, when the
+    table just has REMOVED PARTITIONING, see Bug#42438
+  */
+  if (m_file)
+  {
+    file_array= m_file;
+    DBUG_ASSERT(*file_array);
+    do
+    {
+      (*file_array)->change_table_ptr(table_arg, share);
+    } while (*(++file_array));
+  }
+
+  if (m_added_file && m_added_file[0])
+  {
+    /* if in middle of a drop/rename etc */
+    file_array= m_added_file;
+    do
+    {
+      (*file_array)->change_table_ptr(table_arg, share);
+    } while (*(++file_array));
+  }
+}
+
+
+/**
+  Handle delete and rename table
+
+    @param from         Full path of old table
+    @param to           Full path of new table. May be NULL in case of delete
+
+  @return Operation status
+    @retval >0  Error
+    @retval 0   Success
+
+  @note  Common routine to handle delete_table and rename_table.
+  The routine uses the partition handler file to get the
+  names of the partition instances. Both these routines
+  are called after creating the handler without table
+  object and thus the file is needed to discover the
+  names of the partitions and the underlying storage engines.
+*/
+
+uint ha_partition::del_ren_table(const char *from, const char *to)
+{
+  int save_error= 0;
+  int error;
+  char from_buff[FN_REFLEN + 1], to_buff[FN_REFLEN + 1],
+       from_lc_buff[FN_REFLEN], to_lc_buff[FN_REFLEN];
+  char *name_buffer_ptr;
+  const char *from_path;
+  const char *to_path= NULL;
+  uint i;
+  handler **file, **abort_file;
+  THD *thd= ha_thd();
+  DBUG_ENTER("ha_partition::del_ren_table");
+
+  if (get_from_handler_file(from, thd->mem_root, false))
+    DBUG_RETURN(my_errno ? my_errno : ENOENT);
+  DBUG_ASSERT(m_file_buffer);
+  DBUG_PRINT("enter", ("from: (%s) to: (%s)", from, to ? to : "(nil)"));
+  name_buffer_ptr= m_name_buffer_ptr;
+
+  file= m_file;
+  /* The command should be logged with IF EXISTS if using a shared table */
+  if (m_file[0]->ht->flags & HTON_TABLE_MAY_NOT_EXIST_ON_SLAVE)
+    thd->replication_flags|= OPTION_IF_EXISTS;
+
+  if (to == NULL)
+  {
+    /*
+      Delete table, start by delete the .par file. If error, break, otherwise
+      delete as much as possible.
+    */
+    if (unlikely((error= handler::delete_table(from))))
+      DBUG_RETURN(error);
+  }
+
+  if (ha_check_if_updates_are_ignored(thd, partition_ht(),
+                                      to ? "RENAME" : "DROP"))
+    DBUG_RETURN(0);
+
+  /*
+    Since ha_partition has HA_FILE_BASED, it must alter underlying table names
+    if they do not have HA_FILE_BASED and lower_case_table_names == 2.
+    See Bug#37402, for Mac OS X.
+    The appended #P#<partname>[#SP#<subpartname>] will remain in current case.
+    Using the first partitions handler, since mixing handlers is not allowed.
+  */
+  from_path= get_canonical_filename(*file, from, from_lc_buff);
+  if (to != NULL)
+    to_path= get_canonical_filename(*file, to, to_lc_buff);
+  i= 0;
+  do
+  {
+    if (unlikely((error= create_partition_name(from_buff, sizeof(from_buff),
+                                               from_path, name_buffer_ptr,
+                                               NORMAL_PART_NAME, FALSE))))
+      goto rename_error;
+
+    if (to != NULL)
+    {                                           // Rename branch
+      if (unlikely((error= create_partition_name(to_buff, sizeof(to_buff),
+                                                 to_path, name_buffer_ptr,
+                                                 NORMAL_PART_NAME, FALSE))))
+        goto rename_error;
+      error= (*file)->ha_rename_table(from_buff, to_buff);
+      if (unlikely(error))
+        goto rename_error;
+    }
+    else                                        // delete branch
+    {
+      error= (*file)->delete_table(from_buff);
+    }
+    name_buffer_ptr= strend(name_buffer_ptr) + 1;
+    if (unlikely(error))
+      save_error= error;
+    i++;
+  } while (*(++file));
+  if (to != NULL)
+  {
+    if (unlikely((error= handler::rename_table(from, to))))
+    {
+      /* Try to revert everything, ignore errors */
+      (void) handler::rename_table(to, from);
+      goto rename_error;
+    }
+  }
+
+  /* Update .par file in the handlers that supports it */
+  if ((*m_file)->ht->create_partitioning_metadata)
+  {
+    error= (*m_file)->ht->create_partitioning_metadata(to, from,
+                                                       to == NULL ?
+                                                       CHF_DELETE_FLAG :
+                                                       CHF_RENAME_FLAG);
+    DBUG_EXECUTE_IF("failed_create_partitioning_metadata",
+                    { my_message_sql(ER_OUT_OF_RESOURCES,"Simulated crash",MYF(0));
+                      error= 1;
+                    });
+    if (error)
+    {
+      if (to)
+      {
+        (void) handler::rename_table(to, from);
+        (void) (*m_file)->ht->create_partitioning_metadata(from, to,
+                                                           CHF_RENAME_FLAG);
+        goto rename_error;
+      }
+      else
+        save_error=error;
+    }
+  }
+  DBUG_RETURN(save_error);
+
+rename_error:
+  name_buffer_ptr= m_name_buffer_ptr;
+  for (abort_file= file, file= m_file; file < abort_file; file++)
+  {
+    /* Revert the rename, back from 'to' to the original 'from' */
+    if (!create_partition_name(from_buff, sizeof(from_buff), from_path,
+                               name_buffer_ptr, NORMAL_PART_NAME, FALSE) &&
+        !create_partition_name(to_buff, sizeof(to_buff), to_path,
+                               name_buffer_ptr, NORMAL_PART_NAME, FALSE))
+    {
+      /* Ignore error here */
+      (void) (*file)->ha_rename_table(to_buff, from_buff);
+    }
+    name_buffer_ptr= strend(name_buffer_ptr) + 1;
+  }
+  DBUG_RETURN(error);
+}
+
+uint ha_partition::count_query_cache_dependant_tables(uint8 *tables_type)
+{
+  DBUG_ENTER("ha_partition::count_query_cache_dependant_tables");
+  /* Here we rely on the fact that all tables are of the same type */
+  uint8 type= m_file[0]->table_cache_type();
+  (*tables_type)|= type;
+  DBUG_PRINT("enter", ("cnt: %u", (uint) m_tot_parts));
+  /*
+    We need save underlying tables only for HA_CACHE_TBL_ASKTRANSACT:
+    HA_CACHE_TBL_NONTRANSACT - because all changes goes through partition table
+    HA_CACHE_TBL_NOCACHE - because will not be cached
+    HA_CACHE_TBL_TRANSACT - QC need to know that such type present
+  */
+  DBUG_RETURN(type == HA_CACHE_TBL_ASKTRANSACT ? m_tot_parts : 0);
+}
+
+my_bool ha_partition::
+reg_query_cache_dependant_table(THD *thd,
+                                char *engine_key, uint engine_key_len,
+                                char *cache_key, uint cache_key_len,
+                                uint8 type,
+                                Query_cache *cache,
+                                Query_cache_block_table **block_table,
+                                handler *file,
+                                uint *n)
+{
+  DBUG_ENTER("ha_partition::reg_query_cache_dependant_table");
+  qc_engine_callback engine_callback;
+  ulonglong engine_data;
+  /* ask undelying engine */
+  if (!file->register_query_cache_table(thd, engine_key,
+                                        engine_key_len,
+                                        &engine_callback,
+                                        &engine_data))
+  {
+    DBUG_PRINT("qcache", ("Handler does not allow caching for %.*s",
+                          engine_key_len, engine_key));
+    /*
+      As this can change from call to call, don't reset set
+      thd->lex->safe_to_cache_query
+    */
+    thd->query_cache_is_applicable= 0;        // Query can't be cached
+    DBUG_RETURN(TRUE);
+  }
+  (++(*block_table))->n= ++(*n);
+  if (!cache->insert_table(thd, cache_key_len,
+                           cache_key, (*block_table),
+                           (uint32) table_share->db.length,
+                           (uint8) (cache_key_len -
+                                    table_share->table_cache_key.length),
+                           type,
+                           engine_callback, engine_data,
+                           FALSE))
+    DBUG_RETURN(TRUE);
+  DBUG_RETURN(FALSE);
+}
+
+
+my_bool ha_partition::
+register_query_cache_dependant_tables(THD *thd,
+                                      Query_cache *cache,
+                                      Query_cache_block_table **block_table,
+                                      uint *n)
+{
+  char *engine_key_end, *query_cache_key_end;
+  uint i;
+  uint num_parts= m_part_info->num_parts;
+  uint num_subparts= m_part_info->num_subparts;
+  int diff_length;
+  List_iterator<partition_element> part_it(m_part_info->partitions);
+  char engine_key[FN_REFLEN], query_cache_key[FN_REFLEN];
+  DBUG_ENTER("ha_partition::register_query_cache_dependant_tables");
+
+  /* see ha_partition::count_query_cache_dependant_tables */
+  if (m_file[0]->table_cache_type() != HA_CACHE_TBL_ASKTRANSACT)
+    DBUG_RETURN(FALSE); // nothing to register
+
+  /* prepare static part of the key */
+  memcpy(engine_key, table_share->normalized_path.str,
+         table_share->normalized_path.length);
+  memcpy(query_cache_key, table_share->table_cache_key.str,
+         table_share->table_cache_key.length);
+
+  diff_length= ((int) table_share->table_cache_key.length -
+                (int) table_share->normalized_path.length -1);
+
+  engine_key_end= engine_key + table_share->normalized_path.length;
+  query_cache_key_end= query_cache_key + table_share->table_cache_key.length -1;
+
+  engine_key_end[0]= engine_key_end[2]= query_cache_key_end[0]=
+    query_cache_key_end[2]= '#';
+  query_cache_key_end[1]= engine_key_end[1]= 'P';
+  engine_key_end+= 3;
+  query_cache_key_end+= 3;
+
+  i= 0;
+  do
+  {
+    partition_element *part_elem= part_it++;
+    char *engine_pos= strmov(engine_key_end, part_elem->partition_name);
+    if (m_is_sub_partitioned)
+    {
+      List_iterator<partition_element> subpart_it(part_elem->subpartitions);
+      partition_element *sub_elem;
+      uint j= 0, part;
+      engine_pos[0]= engine_pos[3]= '#';
+      engine_pos[1]= 'S';
+      engine_pos[2]= 'P';
+      engine_pos += 4;
+      do
+      {
+        char *end;
+        uint length;
+        sub_elem= subpart_it++;
+        part= i * num_subparts + j;
+        /* we store the end \0 as part of the key */
+        end= strmov(engine_pos, sub_elem->partition_name) + 1;
+        length= (uint)(end - engine_key);
+        /* Copy the suffix and end 0 to query cache key */
+        memcpy(query_cache_key_end, engine_key_end, (end - engine_key_end));
+        if (reg_query_cache_dependant_table(thd, engine_key, length,
+                                            query_cache_key,
+                                            length + diff_length,
+                                            m_file[part]->table_cache_type(),
+                                            cache,
+                                            block_table, m_file[part],
+                                            n))
+          DBUG_RETURN(TRUE);
+      } while (++j < num_subparts);
+    }
+    else
+    {
+      char *end= engine_pos+1;                  // copy end \0
+      uint length= (uint)(end - engine_key);
+      /* Copy the suffix and end 0 to query cache key */
+      memcpy(query_cache_key_end, engine_key_end, (end - engine_key_end));
+      if (reg_query_cache_dependant_table(thd, engine_key, length,
+                                          query_cache_key,
+                                          length + diff_length,
+                                          m_file[i]->table_cache_type(),
+                                          cache,
+                                          block_table, m_file[i],
+                                          n))
+        DBUG_RETURN(TRUE);
+    }
+  } while (++i < num_parts);
+  DBUG_PRINT("info", ("cnt: %u", (uint)m_tot_parts));
+  DBUG_RETURN(FALSE);
+}
+
+
+/**
+  Set up table share object before calling create on underlying handler
+
+  @param table             Table object
+  @param info              Create info
+  @param part_elem[in,out] Pointer to used partition_element, searched if NULL
+
+  @return    status
+    @retval  TRUE  Error
+    @retval  FALSE Success
+
+  @details
+    Set up
+    1) Comment on partition
+    2) MAX_ROWS, MIN_ROWS on partition
+    3) Index file name on partition
+    4) Data file name on partition
+*/
+
+int ha_partition::set_up_table_before_create(TABLE *tbl,
+                    const char *partition_name_with_path,
+                    HA_CREATE_INFO *info,
+                    partition_element *part_elem)
+{
+  int error= 0;
+  LEX_CSTRING part_name;
+  THD *thd= ha_thd();
+  DBUG_ENTER("set_up_table_before_create");
+
+  DBUG_ASSERT(part_elem);
+
+  if (!part_elem)
+    DBUG_RETURN(1);
+  tbl->s->max_rows= part_elem->part_max_rows;
+  tbl->s->min_rows= part_elem->part_min_rows;
+  part_name.str= strrchr(partition_name_with_path, FN_LIBCHAR)+1;
+  part_name.length= strlen(part_name.str);
+  if ((part_elem->index_file_name &&
+      (error= append_file_to_dir(thd,
+                                 (const char**)&part_elem->index_file_name,
+                                 &part_name))) ||
+      (part_elem->data_file_name &&
+      (error= append_file_to_dir(thd,
+                                 (const char**)&part_elem->data_file_name,
+                                 &part_name))))
+  {
+    DBUG_RETURN(error);
+  }
+  info->index_file_name= part_elem->index_file_name;
+  info->data_file_name= part_elem->data_file_name;
+  info->connect_string= part_elem->connect_string;
+  if (info->connect_string.length)
+    info->used_fields|= HA_CREATE_USED_CONNECTION;
+  tbl->s->connect_string= part_elem->connect_string;
+  DBUG_RETURN(0);
+}
+
+
+/*
+  Add two names together
+
+  SYNOPSIS
+    name_add()
+    out:dest                          Destination string
+    first_name                        First name
+    sec_name                          Second name
+
+  RETURN VALUE
+    >0                                Error
+    0                                 Success
+
+  DESCRIPTION
+    Routine used to add two names with '_' in between then. Service routine
+    to create_handler_file
+    Include the NULL in the count of characters since it is needed as separator
+    between the partition names.
+*/
+
+static uint name_add(char *dest, const char *first_name, const char *sec_name)
+{
+  return (uint) (strxmov(dest, first_name, "#SP#", sec_name, NullS) -dest) + 1;
+}
+
+
+/**
+  Create the special .par file
+
+  @param name  Full path of table name
+
+  @return Operation status
+    @retval FALSE  Error code
+    @retval TRUE   Success
+
+  @note
+    Method used to create handler file with names of partitions, their
+    engine types and the number of partitions.
+*/
+
+bool ha_partition::create_handler_file(const char *name)
+{
+  partition_element *part_elem, *subpart_elem;
+  size_t i, j, part_name_len, subpart_name_len;
+  size_t tot_partition_words, tot_name_len, num_parts;
+  size_t tot_parts= 0;
+  size_t tot_len_words, tot_len_byte, chksum, tot_name_words;
+  char *name_buffer_ptr;
+  uchar *file_buffer, *engine_array;
+  bool result= TRUE;
+  char file_name[FN_REFLEN];
+  char part_name[FN_REFLEN];
+  char subpart_name[FN_REFLEN];
+  File file;
+  List_iterator_fast <partition_element> part_it(m_part_info->partitions);
+  DBUG_ENTER("create_handler_file");
+
+  num_parts= m_part_info->partitions.elements;
+  DBUG_PRINT("enter", ("table name: %s  num_parts: %zu", name, num_parts));
+  tot_name_len= 0;
+  for (i= 0; i < num_parts; i++)
+  {
+    part_elem= part_it++;
+    if (part_elem->part_state != PART_NORMAL &&
+        part_elem->part_state != PART_TO_BE_ADDED &&
+        part_elem->part_state != PART_CHANGED)
+      continue;
+    tablename_to_filename(part_elem->partition_name, part_name,
+                          FN_REFLEN);
+    part_name_len= strlen(part_name);
+    if (!m_is_sub_partitioned)
+    {
+      tot_name_len+= part_name_len + 1;
+      tot_parts++;
+    }
+    else
+    {
+      List_iterator_fast <partition_element> sub_it(part_elem->subpartitions);
+      for (j= 0; j < m_part_info->num_subparts; j++)
+      {
+	subpart_elem= sub_it++;
+        tablename_to_filename(subpart_elem->partition_name,
+                              subpart_name,
+                              FN_REFLEN);
+	subpart_name_len= strlen(subpart_name);
+	tot_name_len+= part_name_len + subpart_name_len + 5;
+        tot_parts++;
+      }
+    }
+  }
+  /*
+     File format:
+     Length in words              4 byte
+     Checksum                     4 byte
+     Total number of partitions   4 byte
+     Array of engine types        n * 4 bytes where
+     n = (m_tot_parts + 3)/4
+     Length of name part in bytes 4 bytes
+     (Names in filename format)
+     Name part                    m * 4 bytes where
+     m = ((length_name_part + 3)/4)*4
+
+     All padding bytes are zeroed
+  */
+  tot_partition_words= (tot_parts + PAR_WORD_SIZE - 1) / PAR_WORD_SIZE;
+  tot_name_words= (tot_name_len + PAR_WORD_SIZE - 1) / PAR_WORD_SIZE;
+  /* 4 static words (tot words, checksum, tot partitions, name length) */
+  tot_len_words= 4 + tot_partition_words + tot_name_words;
+  tot_len_byte= PAR_WORD_SIZE * tot_len_words;
+  if (!(file_buffer= (uchar *) my_malloc(key_memory_ha_partition_file,
+                                         tot_len_byte, MYF(MY_ZEROFILL))))
+    DBUG_RETURN(TRUE);
+  engine_array= (file_buffer + PAR_ENGINES_OFFSET);
+  name_buffer_ptr= (char*) (engine_array + tot_partition_words * PAR_WORD_SIZE
+                            + PAR_WORD_SIZE);
+  part_it.rewind();
+  for (i= 0; i < num_parts; i++)
+  {
+    part_elem= part_it++;
+    if (part_elem->part_state != PART_NORMAL &&
+        part_elem->part_state != PART_TO_BE_ADDED &&
+        part_elem->part_state != PART_CHANGED)
+      continue;
+    if (!m_is_sub_partitioned)
+    {
+      tablename_to_filename(part_elem->partition_name, part_name, FN_REFLEN);
+      name_buffer_ptr= strmov(name_buffer_ptr, part_name)+1;
+      *engine_array= (uchar) ha_legacy_type(part_elem->engine_type);
+      DBUG_PRINT("info", ("engine: %u", *engine_array));
+      engine_array++;
+    }
+    else
+    {
+      List_iterator_fast <partition_element> sub_it(part_elem->subpartitions);
+      for (j= 0; j < m_part_info->num_subparts; j++)
+      {
+	subpart_elem= sub_it++;
+        tablename_to_filename(part_elem->partition_name, part_name,
+                              FN_REFLEN);
+        tablename_to_filename(subpart_elem->partition_name, subpart_name,
+                              FN_REFLEN);
+	name_buffer_ptr+= name_add(name_buffer_ptr,
+				   part_name,
+				   subpart_name);
+        *engine_array= (uchar) ha_legacy_type(subpart_elem->engine_type);
+        DBUG_PRINT("info", ("engine: %u", *engine_array));
+	engine_array++;
+      }
+    }
+  }
+  chksum= 0;
+  int4store(file_buffer, tot_len_words);
+  int4store(file_buffer + PAR_NUM_PARTS_OFFSET, tot_parts);
+  int4store(file_buffer + PAR_ENGINES_OFFSET +
+            (tot_partition_words * PAR_WORD_SIZE),
+            tot_name_len);
+  for (i= 0; i < tot_len_words; i++)
+    chksum^= uint4korr(file_buffer + PAR_WORD_SIZE * i);
+  int4store(file_buffer + PAR_CHECKSUM_OFFSET, chksum);
+  /*
+    Add .par extension to the file name.
+    Create and write and close file
+    to be used at open, delete_table and rename_table
+  */
+  fn_format(file_name, name, "", ha_par_ext, MY_APPEND_EXT);
+  if ((file= mysql_file_create(key_file_ha_partition_par,
+                               file_name, CREATE_MODE, O_RDWR | O_TRUNC,
+                               MYF(MY_WME))) >= 0)
+  {
+    result= mysql_file_write(file, (uchar *) file_buffer, tot_len_byte,
+                             MYF(MY_WME | MY_NABP)) != 0;
+
+    /* Write connection information (for federatedx engine) */
+    part_it.rewind();
+    for (i= 0; i < num_parts && !result; i++)
+    {
+      uchar buffer[4];
+      part_elem= part_it++;
+      size_t length= part_elem->connect_string.length;
+      int4store(buffer, length);
+      if (my_write(file, buffer, 4, MYF(MY_WME | MY_NABP)) ||
+          my_write(file, (uchar *) part_elem->connect_string.str, length,
+                   MYF(MY_WME | MY_NABP)))
+      {
+        result= TRUE;
+        break;
+      }
+    }
+    (void) mysql_file_close(file, MYF(0));
+    if (result)
+      mysql_file_delete(key_file_ha_partition_par, file_name, MYF(MY_WME));
+  }
+  else
+    result= TRUE;
+  my_free(file_buffer);
+  DBUG_RETURN(result);
+}
+
+
+/**
+  Clear handler variables and free some memory
+*/
+
+void ha_partition::clear_handler_file()
+{
+  if (m_engine_array)
+    plugin_unlock_list(NULL, m_engine_array, m_tot_parts);
+  free_root(&m_mem_root, MYF(MY_KEEP_PREALLOC));
+  m_file_buffer= NULL;
+  m_engine_array= NULL;
+  m_connect_string= NULL;
+}
+
+
+/**
+  Create underlying handler objects
+
+  @param mem_root  Allocate memory through this
+
+  @return Operation status
+    @retval TRUE   Error
+    @retval FALSE  Success
+*/
+
+bool ha_partition::create_handlers(MEM_ROOT *mem_root)
+{
+  uint i;
+  uint alloc_len= (m_tot_parts + 1) * sizeof(handler*);
+  handlerton *hton0;
+  DBUG_ENTER("create_handlers");
+
+  if (!(m_file= (handler **) alloc_root(mem_root, alloc_len)))
+    DBUG_RETURN(TRUE);
+  m_file_tot_parts= m_tot_parts;
+  bzero((char*) m_file, alloc_len);
+  for (i= 0; i < m_tot_parts; i++)
+  {
+    handlerton *hton= plugin_data(m_engine_array[i], handlerton*);
+    if (!(m_file[i]= get_new_handler(table_share, mem_root, hton)))
+      DBUG_RETURN(TRUE);
+    DBUG_PRINT("info", ("engine_type: %u", hton->db_type));
+  }
+  /* For the moment we only support partition over the same table engine */
+  hton0= plugin_data(m_engine_array[0], handlerton*);
+  if (hton0 == myisam_hton)
+  {
+    DBUG_PRINT("info", ("MyISAM"));
+    m_myisam= TRUE;
+  }
+  /* INNODB may not be compiled in... */
+  else if (ha_legacy_type(hton0) == DB_TYPE_INNODB)
+  {
+    DBUG_PRINT("info", ("InnoDB"));
+    m_innodb= TRUE;
+  }
+  DBUG_RETURN(FALSE);
+}
+
+
+/*
+  Create underlying handler objects from partition info
+
+  SYNOPSIS
+    new_handlers_from_part_info()
+    mem_root		Allocate memory through this
+
+  RETURN VALUE
+    TRUE                  Error
+    FALSE                 Success
+*/
+
+bool ha_partition::new_handlers_from_part_info(MEM_ROOT *mem_root)
+{
+  uint i, j, part_count;
+  partition_element *part_elem;
+  uint alloc_len= (m_tot_parts + 1) * sizeof(handler*);
+  List_iterator_fast <partition_element> part_it(m_part_info->partitions);
+  DBUG_ENTER("ha_partition::new_handlers_from_part_info");
+
+  if (!(m_file= (handler **) alloc_root(mem_root, alloc_len)))
+    goto error;
+
+  m_file_tot_parts= m_tot_parts;
+  bzero((char*) m_file, alloc_len);
+  DBUG_ASSERT(m_part_info->num_parts > 0);
+
+  i= 0;
+  part_count= 0;
+  /*
+    Don't know the size of the underlying storage engine, invent a number of
+    bytes allocated for error message if allocation fails
+  */
+  do
+  {
+    part_elem= part_it++;
+    if (m_is_sub_partitioned)
+    {
+      for (j= 0; j < m_part_info->num_subparts; j++)
+      {
+	if (!(m_file[part_count++]= get_new_handler(table_share, mem_root,
+                                                    part_elem->engine_type)))
+          goto error;
+	DBUG_PRINT("info", ("engine_type: %u",
+                   (uint) ha_legacy_type(part_elem->engine_type)));
+      }
+    }
+    else
+    {
+      if (!(m_file[part_count++]= get_new_handler(table_share, mem_root,
+                                                  part_elem->engine_type)))
+        goto error;
+      DBUG_PRINT("info", ("engine_type: %u",
+                 (uint) ha_legacy_type(part_elem->engine_type)));
+    }
+  } while (++i < m_part_info->num_parts);
+  if (part_elem->engine_type == myisam_hton)
+  {
+    DBUG_PRINT("info", ("MyISAM"));
+    m_myisam= TRUE;
+  }
+  DBUG_RETURN(FALSE);
+error:
+  DBUG_RETURN(TRUE);
+}
+
+
+/**
+  Read the .par file to get the partitions engines and names
+
+  @param name  Name of table file (without extension)
+
+  @return Operation status
+    @retval true   Failure
+    @retval false  Success
+
+  @note On success, m_file_buffer is allocated and must be
+  freed by the caller. m_name_buffer_ptr and m_tot_parts is also set.
+*/
+
+bool ha_partition::read_par_file(const char *name)
+{
+  char buff[FN_REFLEN];
+  uchar *tot_name_len_offset;
+  File file;
+  uchar *file_buffer;
+  uint i, len_bytes, len_words, tot_partition_words, tot_name_words, chksum;
+  DBUG_ENTER("ha_partition::read_par_file");
+  DBUG_PRINT("enter", ("table name: '%s'", name));
+
+  if (m_file_buffer)
+    DBUG_RETURN(false);
+  fn_format(buff, name, "", ha_par_ext, MY_APPEND_EXT);
+
+  /* Following could be done with mysql_file_stat to read in whole file */
+  if ((file= mysql_file_open(key_file_ha_partition_par,
+                             buff, O_RDONLY | O_SHARE, MYF(0))) < 0)
+    DBUG_RETURN(TRUE);
+  if (mysql_file_read(file, (uchar *) &buff[0], PAR_WORD_SIZE, MYF(MY_NABP)))
+    goto err1;
+  len_words= uint4korr(buff);
+  len_bytes= PAR_WORD_SIZE * len_words;
+  if (mysql_file_seek(file, 0, MY_SEEK_SET, MYF(0)) == MY_FILEPOS_ERROR)
+    goto err1;
+  if (!(file_buffer= (uchar*) alloc_root(&m_mem_root, len_bytes)))
+    goto err1;
+  if (mysql_file_read(file, file_buffer, len_bytes, MYF(MY_NABP)))
+    goto err2;
+
+  chksum= 0;
+  for (i= 0; i < len_words; i++)
+    chksum ^= uint4korr((file_buffer) + PAR_WORD_SIZE * i);
+  if (chksum)
+    goto err2;
+  m_tot_parts= uint4korr((file_buffer) + PAR_NUM_PARTS_OFFSET);
+  DBUG_PRINT("info", ("No of parts: %u", m_tot_parts));
+  tot_partition_words= (m_tot_parts + PAR_WORD_SIZE - 1) / PAR_WORD_SIZE;
+
+  tot_name_len_offset= file_buffer + PAR_ENGINES_OFFSET +
+                       PAR_WORD_SIZE * tot_partition_words;
+  tot_name_words= (uint4korr(tot_name_len_offset) + PAR_WORD_SIZE - 1) /
+                  PAR_WORD_SIZE;
+  /*
+    Verify the total length = tot size word, checksum word, num parts word +
+    engines array + name length word + name array.
+  */
+  if (len_words != (tot_partition_words + tot_name_words + 4))
+    goto err2;
+  m_file_buffer= file_buffer;          // Will be freed in clear_handler_file()
+  m_name_buffer_ptr= (char*) (tot_name_len_offset + PAR_WORD_SIZE);
+
+  if (!(m_connect_string= (LEX_CSTRING*)
+        alloc_root(&m_mem_root, m_tot_parts * sizeof(LEX_CSTRING))))
+    goto err2;
+  bzero(m_connect_string, m_tot_parts * sizeof(LEX_CSTRING));
+
+  /* Read connection arguments (for federated X engine) */
+  for (i= 0; i < m_tot_parts; i++)
+  {
+    LEX_CSTRING connect_string;
+    uchar buffer[4];
+    char *tmp;
+    if (my_read(file, buffer, 4, MYF(MY_NABP)))
+    {
+      /* No extra options; Probably not a federatedx engine */
+      break;
+    }
+    connect_string.length= uint4korr(buffer);
+    connect_string.str= tmp= (char*) alloc_root(&m_mem_root,
+                                                connect_string.length+1);
+    if (my_read(file, (uchar*) connect_string.str, connect_string.length,
+                MYF(MY_NABP)))
+      break;
+    tmp[connect_string.length]= 0;
+    m_connect_string[i]= connect_string;
+  }
+
+  (void) mysql_file_close(file, MYF(0));
+  DBUG_RETURN(false);
+
+err2:
+err1:
+  (void) mysql_file_close(file, MYF(0));
+  DBUG_RETURN(true);
+}
+
+
+/**
+  Setup m_engine_array
+
+  @param mem_root  MEM_ROOT to use for allocating new handlers
+
+  @return Operation status
+    @retval false  Success
+    @retval true   Failure
+*/
+
+bool ha_partition::setup_engine_array(MEM_ROOT *mem_root)
+{
+  uint i;
+  uchar *buff;
+  handlerton **engine_array, *first_engine;
+  enum legacy_db_type db_type, first_db_type;
+
+  DBUG_ASSERT(!m_file);
+  DBUG_ENTER("ha_partition::setup_engine_array");
+  engine_array= (handlerton **) my_alloca(m_tot_parts * sizeof(handlerton*));
+  if (!engine_array)
+    DBUG_RETURN(true);
+
+  buff= (uchar *) (m_file_buffer + PAR_ENGINES_OFFSET);
+  first_db_type= (enum legacy_db_type) buff[0];
+  first_engine= ha_resolve_by_legacy_type(ha_thd(), first_db_type);
+  if (!first_engine)
+    goto err;
+
+  if (!(m_engine_array= (plugin_ref*)
+        alloc_root(&m_mem_root, m_tot_parts * sizeof(plugin_ref))))
+    goto err;
+
+  for (i= 0; i < m_tot_parts; i++)
+  {
+    db_type= (enum legacy_db_type) buff[i];
+    if (db_type != first_db_type)
+    {
+      DBUG_PRINT("error", ("partition %u engine %d is not same as "
+                           "first partition %d", i, db_type,
+                           (int) first_db_type));
+      DBUG_ASSERT(0);
+      clear_handler_file();
+      goto err;
+    }
+    m_engine_array[i]= ha_lock_engine(NULL, first_engine);
+    if (!m_engine_array[i])
+    {
+      clear_handler_file();
+      goto err;
+    }
+  }
+
+  my_afree(engine_array);
+
+  if (create_handlers(mem_root))
+  {
+    clear_handler_file();
+    DBUG_RETURN(true);
+  }
+
+  DBUG_RETURN(false);
+
+err:
+  my_afree(engine_array);
+  DBUG_RETURN(true);
+}
+
+
+/**
+  Get info about partition engines and their names from the .par file
+
+  @param name      Full path of table name
+  @param mem_root  Allocate memory through this
+  @param is_clone  If it is a clone, don't create new handlers
+
+  @return Operation status
+    @retval true   Error
+    @retval false  Success
+
+  @note Open handler file to get partition names, engine types and number of
+  partitions.
+*/
+
+bool ha_partition::get_from_handler_file(const char *name, MEM_ROOT *mem_root,
+                                         bool is_clone)
+{
+  DBUG_ENTER("ha_partition::get_from_handler_file");
+  DBUG_PRINT("enter", ("table name: '%s'", name));
+
+  if (m_file_buffer)
+    DBUG_RETURN(false);
+
+  if (read_par_file(name))
+    DBUG_RETURN(true);
+
+  if (!is_clone && setup_engine_array(mem_root))
+    DBUG_RETURN(true);
+
+  DBUG_RETURN(false);
+}
+
+
+/****************************************************************************
+                MODULE open/close object
+****************************************************************************/
+
+/**
+  Get the partition name.
+
+  @param       part   Struct containing name and length
+  @param[out]  length Length of the name
+
+  @return Partition name
+*/
+
+static uchar *get_part_name(PART_NAME_DEF *part, size_t *length,
+                            my_bool not_used __attribute__((unused)))
+{
+  *length= part->length;
+  return part->partition_name;
+}
+
+
+/**
+  Insert a partition name in the partition_name_hash.
+
+  @param name        Name of partition
+  @param part_id     Partition id (number)
+  @param is_subpart  Set if the name belongs to a subpartition
+
+  @return Operation status
+    @retval true   Failure
+    @retval false  Success
+*/
+
+bool ha_partition::insert_partition_name_in_hash(const char *name, uint part_id,
+                                                 bool is_subpart)
+{
+  PART_NAME_DEF *part_def;
+  uchar *part_name;
+  size_t part_name_length;
+  DBUG_ENTER("ha_partition::insert_partition_name_in_hash");
+  /*
+    Calculate and store the length here, to avoid doing it when
+    searching the hash.
+  */
+  part_name_length= strlen(name);
+  /*
+    Must use memory that lives as long as table_share.
+    Freed in the Partition_share destructor.
+    Since we use my_multi_malloc, then my_free(part_def) will also free
+    part_name, as a part of my_hash_free.
+  */
+  if (!my_multi_malloc(key_memory_Partition_share, MY_WME,
+                       &part_def, sizeof(PART_NAME_DEF),
+                       &part_name, part_name_length + 1,
+                       NULL))
+    DBUG_RETURN(true);
+  memcpy(part_name, name, part_name_length + 1);
+  part_def->partition_name= part_name;
+  part_def->length= (uint)part_name_length;
+  part_def->part_id= part_id;
+  part_def->is_subpart= is_subpart;
+  if (my_hash_insert(&part_share->partition_name_hash, (uchar *) part_def))
+  {
+    my_free(part_def);
+    DBUG_RETURN(true);
+  }
+  DBUG_RETURN(false);
+}
+
+
+/**
+  Populate the partition_name_hash in part_share.
+*/
+
+bool ha_partition::populate_partition_name_hash()
+{
+  List_iterator<partition_element> part_it(m_part_info->partitions);
+  uint num_parts= m_part_info->num_parts;
+  uint num_subparts= m_is_sub_partitioned ? m_part_info->num_subparts : 1;
+  uint tot_names;
+  uint i= 0;
+  DBUG_ASSERT(part_share);
+
+  DBUG_ENTER("ha_partition::populate_partition_name_hash");
+
+  /*
+    partition_name_hash is only set once and never changed
+    -> OK to check without locking.
+  */
+
+  if (part_share->partition_name_hash_initialized)
+    DBUG_RETURN(false);
+  lock_shared_ha_data();
+  if (part_share->partition_name_hash_initialized)
+  {
+    unlock_shared_ha_data();
+    DBUG_RETURN(false);
+  }
+  tot_names= m_is_sub_partitioned ? m_tot_parts + num_parts : num_parts;
+  if (my_hash_init(key_memory_Partition_share,
+                   &part_share->partition_name_hash, system_charset_info,
+                   tot_names, 0, 0, (my_hash_get_key) get_part_name, my_free,
+                   HASH_UNIQUE))
+  {
+    unlock_shared_ha_data();
+    DBUG_RETURN(TRUE);
+  }
+
+  do
+  {
+    partition_element *part_elem= part_it++;
+    DBUG_ASSERT(part_elem->part_state == PART_NORMAL);
+    if (part_elem->part_state == PART_NORMAL)
+    {
+      if (insert_partition_name_in_hash(part_elem->partition_name,
+                                        i * num_subparts, false))
+        goto err;
+      if (m_is_sub_partitioned)
+      {
+        List_iterator<partition_element>
+                                    subpart_it(part_elem->subpartitions);
+        partition_element *sub_elem;
+        uint j= 0;
+        do
+        {
+          sub_elem= subpart_it++;
+          if (insert_partition_name_in_hash(sub_elem->partition_name,
+                                            i * num_subparts + j, true))
+            goto err;
+
+        } while (++j < num_subparts);
+      }
+    }
+  } while (++i < num_parts);
+
+  part_share->partition_name_hash_initialized= true;
+  unlock_shared_ha_data();
+
+  DBUG_RETURN(FALSE);
+err:
+  my_hash_free(&part_share->partition_name_hash);
+  unlock_shared_ha_data();
+
+  DBUG_RETURN(TRUE);
+}
+
+
+/**
+  Set Handler_share pointer and allocate Handler_share pointers
+  for each partition and set those.
+
+  @param ha_share_arg  Where to store/retrieve the Partitioning_share pointer
+                       to be shared by all instances of the same table.
+
+  @return Operation status
+    @retval true  Failure
+    @retval false Success
+*/
+
+bool ha_partition::set_ha_share_ref(Handler_share **ha_share_arg)
+{
+  Handler_share **ha_shares;
+  uint i;
+  DBUG_ENTER("ha_partition::set_ha_share_ref");
+
+  DBUG_ASSERT(!part_share);
+  DBUG_ASSERT(table_share);
+  DBUG_ASSERT(!m_is_clone_of);
+  DBUG_ASSERT(m_tot_parts);
+  if (handler::set_ha_share_ref(ha_share_arg))
+    DBUG_RETURN(true);
+  if (!(part_share= get_share()))
+    DBUG_RETURN(true);
+  DBUG_ASSERT(part_share->partitions_share_refs.num_parts >= m_tot_parts);
+  ha_shares= part_share->partitions_share_refs.ha_shares;
+  for (i= 0; i < m_tot_parts; i++)
+  {
+    if (m_file[i]->set_ha_share_ref(&ha_shares[i]))
+      DBUG_RETURN(true);
+  }
+  DBUG_RETURN(false);
+}
+
+
+/**
+  Get the PARTITION_SHARE for the table.
+
+  @return Operation status
+    @retval true   Error
+    @retval false  Success
+
+  @note Gets or initializes the Partition_share object used by partitioning.
+  The Partition_share is used for handling the auto_increment etc.
+*/
+
+Partition_share *ha_partition::get_share()
+{
+  Partition_share *tmp_share;
+  DBUG_ENTER("ha_partition::get_share");
+  DBUG_ASSERT(table_share);
+
+  lock_shared_ha_data();
+  if (!(tmp_share= static_cast<Partition_share*>(get_ha_share_ptr())))
+  {
+    tmp_share= new Partition_share;
+    if (!tmp_share)
+      goto err;
+    if (tmp_share->init(m_tot_parts))
+    {
+      delete tmp_share;
+      tmp_share= NULL;
+      goto err;
+    }
+    set_ha_share_ptr(static_cast<Handler_share*>(tmp_share));
+  }
+err:
+  unlock_shared_ha_data();
+  DBUG_RETURN(tmp_share);
+}
+
+
+
+/**
+  Helper function for freeing all internal bitmaps.
+*/
+
+void ha_partition::free_partition_bitmaps()
+{
+  /* Initialize the bitmap we use to minimize ha_start_bulk_insert calls */
+  my_bitmap_free(&m_bulk_insert_started);
+  my_bitmap_free(&m_locked_partitions);
+  my_bitmap_free(&m_partitions_to_reset);
+  my_bitmap_free(&m_key_not_found_partitions);
+  my_bitmap_free(&m_opened_partitions);
+  my_bitmap_free(&m_mrr_used_partitions);
+}
+
+
+/**
+  Helper function for initializing all internal bitmaps.
+
+  Note:
+  All bitmaps, including partially allocated, are freed in
+  free_partion_bitmaps()
+*/
+
+bool ha_partition::init_partition_bitmaps()
+{
+  DBUG_ENTER("ha_partition::init_partition_bitmaps");
+
+  /* Initialize the bitmap we use to minimize ha_start_bulk_insert calls */
+  if (my_bitmap_init(&m_bulk_insert_started, NULL, m_tot_parts + 1, FALSE))
+    DBUG_RETURN(true);
+
+  /* Initialize the bitmap we use to keep track of locked partitions */
+  if (my_bitmap_init(&m_locked_partitions, NULL, m_tot_parts, FALSE))
+    DBUG_RETURN(true);
+
+  /*
+    Initialize the bitmap we use to keep track of partitions which may have
+    something to reset in ha_reset().
+  */
+  if (my_bitmap_init(&m_partitions_to_reset, NULL, m_tot_parts, FALSE))
+    DBUG_RETURN(true);
+
+  /*
+    Initialize the bitmap we use to keep track of partitions which returned
+    HA_ERR_KEY_NOT_FOUND from index_read_map.
+  */
+  if (my_bitmap_init(&m_key_not_found_partitions, NULL, m_tot_parts, FALSE))
+    DBUG_RETURN(true);
+
+  if (bitmap_init(&m_mrr_used_partitions, NULL, m_tot_parts, TRUE))
+    DBUG_RETURN(true);
+
+  if (my_bitmap_init(&m_opened_partitions, NULL, m_tot_parts, FALSE))
+    DBUG_RETURN(true);
+
+  m_file_sample= NULL;
+
+  /* Initialize the bitmap for read/lock_partitions */
+  if (!m_is_clone_of)
+  {
+    DBUG_ASSERT(!m_clone_mem_root);
+    if (m_part_info->set_partition_bitmaps(NULL))
+      DBUG_RETURN(true);
+  }
+  DBUG_RETURN(false);
+}
+
+
+/*
+  Open handler object
+SYNOPSIS
+    open()
+    name                  Full path of table name
+    mode                  Open mode flags
+    test_if_locked        ?
+
+  RETURN VALUE
+    >0                    Error
+    0                     Success
+
+  DESCRIPTION
+    Used for opening tables. The name will be the name of the file.
+    A table is opened when it needs to be opened. For instance
+    when a request comes in for a select on the table (tables are not
+    open and closed for each request, they are cached).
+
+    Called from handler.cc by handler::ha_open(). The server opens all tables
+    by calling ha_open() which then calls the handler specific open().
+*/
+
+int ha_partition::open(const char *name, int mode, uint test_if_locked)
+{
+  int error= HA_ERR_INITIALIZATION;
+  handler **file;
+  char name_buff[FN_REFLEN + 1];
+  ulonglong check_table_flags;
+  DBUG_ENTER("ha_partition::open");
+
+  DBUG_ASSERT(table->s == table_share);
+  ref_length= 0;
+  m_mode= mode;
+  m_open_test_lock= test_if_locked;
+  m_part_field_array= m_part_info->full_part_field_array;
+  if (get_from_handler_file(name, &table->mem_root, MY_TEST(m_is_clone_of)))
+    DBUG_RETURN(error);
+  if (populate_partition_name_hash())
+  {
+    DBUG_RETURN(HA_ERR_INITIALIZATION);
+  }
+  m_start_key.length= 0;
+  m_rec0= table->record[0];
+  m_rec_length= table_share->reclength;
+  if (!m_part_ids_sorted_by_num_of_records)
+  {
+    if (!(m_part_ids_sorted_by_num_of_records=
+            (uint32*) my_malloc(key_memory_ha_partition_part_ids,
+                                m_tot_parts * sizeof(uint32), MYF(MY_WME))))
+      DBUG_RETURN(error);
+    uint32 i;
+    /* Initialize it with all partition ids. */
+    for (i= 0; i < m_tot_parts; i++)
+      m_part_ids_sorted_by_num_of_records[i]= i;
+  }
+
+  if (init_partition_bitmaps())
+    goto err_alloc;
+
+  if (!MY_TEST(m_is_clone_of) &&
+      unlikely((error=
+                m_part_info->set_partition_bitmaps(m_partitions_to_open))))
+    goto err_alloc;
+
+  /* Allocate memory used with MMR */
+  if (!(m_range_info= (void **)
+        my_multi_malloc(PSI_INSTRUMENT_ME, MYF(MY_WME),
+                        &m_range_info, sizeof(range_id_t) * m_tot_parts,
+                        &m_stock_range_seq, sizeof(uint) * m_tot_parts,
+                        &m_mrr_buffer, sizeof(HANDLER_BUFFER) * m_tot_parts,
+                        &m_mrr_buffer_size, sizeof(uint) * m_tot_parts,
+                        &m_part_mrr_range_length, sizeof(uint) * m_tot_parts,
+                        &m_part_mrr_range_first,
+                        sizeof(PARTITION_PART_KEY_MULTI_RANGE *) * m_tot_parts,
+                        &m_part_mrr_range_current,
+                        sizeof(PARTITION_PART_KEY_MULTI_RANGE *) * m_tot_parts,
+                        &m_partition_part_key_multi_range_hld,
+                        sizeof(PARTITION_PART_KEY_MULTI_RANGE_HLD) * m_tot_parts,
+                        NullS)))
+    goto err_alloc;
+
+  bzero(m_mrr_buffer, m_tot_parts * sizeof(HANDLER_BUFFER));
+  bzero(m_part_mrr_range_first,
+        sizeof(PARTITION_PART_KEY_MULTI_RANGE *) * m_tot_parts);
+
+  if (m_is_clone_of)
+  {
+    uint i, alloc_len;
+    char *name_buffer_ptr;
+    DBUG_ASSERT(m_clone_mem_root);
+    /* Allocate an array of handler pointers for the partitions handlers. */
+    alloc_len= (m_tot_parts + 1) * sizeof(handler*);
+    if (!(m_file= (handler **) alloc_root(m_clone_mem_root, alloc_len)))
+    {
+      error= HA_ERR_INITIALIZATION;
+      goto err_alloc;
+    }
+    memset(m_file, 0, alloc_len);
+    name_buffer_ptr= m_name_buffer_ptr;
+    /*
+      Populate them by cloning the original partitions. This also opens them.
+      Note that file->ref is allocated too.
+    */
+    file= m_is_clone_of->m_file;
+    for (i= 0; i < m_tot_parts; i++)
+    {
+      if (!bitmap_is_set(&m_is_clone_of->m_opened_partitions, i))
+        continue;
+
+      if (unlikely((error= create_partition_name(name_buff, sizeof(name_buff),
+                                                 name, name_buffer_ptr,
+                                                 NORMAL_PART_NAME, FALSE))))
+        goto err_handler;
+      /* ::clone() will also set ha_share from the original. */
+      if (!(m_file[i]= file[i]->clone(name_buff, m_clone_mem_root)))
+      {
+        error= HA_ERR_INITIALIZATION;
+        file= &m_file[i];
+        goto err_handler;
+      }
+      if (!m_file_sample)
+        m_file_sample= m_file[i];
+      name_buffer_ptr+= strlen(name_buffer_ptr) + 1;
+      bitmap_set_bit(&m_opened_partitions, i);
+    }
+  }
+  else
+  {
+    check_insert_autoincrement();
+    if (unlikely((error= open_read_partitions(name_buff, sizeof(name_buff)))))
+      goto err_handler;
+    m_num_locks= m_file_sample->lock_count();
+  }
+  /*
+    We want to know the upper bound for locks, to allocate enough memory.
+    There is no performance lost if we simply return in lock_count() the
+    maximum number locks needed, only some minor over allocation of memory
+    in get_lock_data().
+  */
+  m_num_locks*= m_tot_parts;
+
+  file= m_file;
+  ref_length= get_open_file_sample()->ref_length;
+  check_table_flags= ((get_open_file_sample()->ha_table_flags() &
+                       ~(PARTITION_DISABLED_TABLE_FLAGS)) |
+                      (PARTITION_ENABLED_TABLE_FLAGS));
+  while (*(++file))
+  {
+    if (!bitmap_is_set(&m_opened_partitions, (uint)(file - m_file)))
+      continue;
+    /* MyISAM can have smaller ref_length for partitions with MAX_ROWS set */
+    set_if_bigger(ref_length, ((*file)->ref_length));
+    /*
+      Verify that all partitions have the same set of table flags.
+      Mask all flags that partitioning enables/disables.
+    */
+    if (check_table_flags != (((*file)->ha_table_flags() &
+                               ~(PARTITION_DISABLED_TABLE_FLAGS)) |
+                              (PARTITION_ENABLED_TABLE_FLAGS)))
+    {
+      error= HA_ERR_INITIALIZATION;
+      /* set file to last handler, so all of them are closed */
+      file= &m_file[m_tot_parts - 1];
+      goto err_handler;
+    }
+  }
+  key_used_on_scan= get_open_file_sample()->key_used_on_scan;
+  implicit_emptied= get_open_file_sample()->implicit_emptied;
+  /*
+    Add 2 bytes for partition id in position ref length.
+    ref_length=max_in_all_partitions(ref_length) + PARTITION_BYTES_IN_POS
+  */
+  ref_length+= PARTITION_BYTES_IN_POS;
+  m_ref_length= ref_length;
+
+  /*
+    Release buffer read from .par file. It will not be reused again after
+    being opened once.
+  */
+  clear_handler_file();
+
+  /*
+    Some handlers update statistics as part of the open call. This will in
+    some cases corrupt the statistics of the partition handler and thus
+    to ensure we have correct statistics we call info from open after
+    calling open on all individual handlers.
+  */
+  m_handler_status= handler_opened;
+  if (m_part_info->part_expr)
+    m_part_func_monotonicity_info=
+                            m_part_info->part_expr->get_monotonicity_info();
+  else if (m_part_info->list_of_part_fields)
+    m_part_func_monotonicity_info= MONOTONIC_STRICT_INCREASING;
+  info(HA_STATUS_VARIABLE | HA_STATUS_CONST | HA_STATUS_OPEN);
+  DBUG_RETURN(0);
+
+err_handler:
+  DEBUG_SYNC(ha_thd(), "partition_open_error");
+  DBUG_ASSERT(m_tot_parts > 0);
+  for (uint i= m_tot_parts - 1; ; --i)
+  {
+    if (bitmap_is_set(&m_opened_partitions, i))
+      m_file[i]->ha_close();
+    if (!i)
+      break;
+  }
+err_alloc:
+  free_partition_bitmaps();
+  my_free(m_range_info);
+  m_range_info= 0;
+
+  DBUG_RETURN(error);
+}
+
+
+/*
+  Disabled since it is not possible to prune yet.
+  without pruning, it need to rebind/unbind every partition in every
+  statement which uses a table from the table cache. Will also use
+  as many PSI_tables as there are partitions.
+*/
+
+#ifdef HAVE_M_PSI_PER_PARTITION
+void ha_partition::unbind_psi()
+{
+  uint i;
+
+  DBUG_ENTER("ha_partition::unbind_psi");
+  handler::unbind_psi();
+  for (i= 0; i < m_tot_parts; i++)
+  {
+    DBUG_ASSERT(m_file[i] != NULL);
+    m_file[i]->unbind_psi();
+  }
+  DBUG_VOID_RETURN;
+}
+
+int ha_partition::rebind()
+{
+  uint i;
+
+  DBUG_ENTER("ha_partition::rebind");
+  if (int error= handler::rebind())
+    DBUG_RETURN(error);
+  for (i= 0; i < m_tot_parts; i++)
+  {
+    DBUG_ASSERT(m_file[i] != NULL);
+    if (int error= m_file[i]->rebind())
+    {
+      while (i)
+        m_file[--i]->unbind_psi();
+      handler::unbind_psi();
+      DBUG_RETURN(error);
+    }
+  }
+  DBUG_RETURN(0);
+}
+#endif /* HAVE_M_PSI_PER_PARTITION */
+
+
+/*
+  Check if the table definition has changed for the part tables
+  We use the first partition for the check.
+*/
+
+int ha_partition::discover_check_version()
+{
+  return m_file[0]->discover_check_version();
+}
+
+/**
+  Clone the open and locked partitioning handler.
+
+  @param  mem_root  MEM_ROOT to use.
+
+  @return Pointer to the successfully created clone or NULL
+
+  @details
+  This function creates a new ha_partition handler as a clone/copy. The
+  original (this) must already be opened and locked. The clone will use
+  the originals m_part_info.
+  It also allocates memory for ref + ref_dup.
+  In ha_partition::open() it will clone its original handlers partitions
+  which will allocate then on the correct MEM_ROOT and also open them.
+*/
+
+handler *ha_partition::clone(const char *name, MEM_ROOT *mem_root)
+{
+  ha_partition *new_handler;
+
+  DBUG_ENTER("ha_partition::clone");
+  new_handler= new (mem_root) ha_partition(ht, table_share, m_part_info,
+                                           this, mem_root);
+  if (!new_handler)
+    DBUG_RETURN(NULL);
+
+  /*
+    We will not clone each partition's handler here, it will be done in
+    ha_partition::open() for clones. Also set_ha_share_ref is not needed
+    here, since 1) ha_share is copied in the constructor used above
+    2) each partition's cloned handler will set it from its original.
+  */
+
+  /*
+    Allocate new_handler->ref here because otherwise ha_open will allocate it
+    on this->table->mem_root and we will not be able to reclaim that memory
+    when the clone handler object is destroyed.
+  */
+  if (!(new_handler->ref= (uchar*) alloc_root(mem_root,
+                                              ALIGN_SIZE(m_ref_length)*2)))
+    goto err;
+
+  if (new_handler->ha_open(table, name,
+                           table->db_stat,
+                           HA_OPEN_IGNORE_IF_LOCKED | HA_OPEN_NO_PSI_CALL))
+    goto err;
+
+  DBUG_RETURN((handler*) new_handler);
+
+err:
+  delete new_handler;
+  DBUG_RETURN(NULL);
+}
+
+
+/*
+  Close handler object
+
+  SYNOPSIS
+    close()
+
+  RETURN VALUE
+    >0                   Error code
+    0                    Success
+
+  DESCRIPTION
+    Called from sql_base.cc, sql_select.cc, and table.cc.
+    In sql_select.cc it is only used to close up temporary tables or during
+    the process where a temporary table is converted over to being a
+    myisam table.
+    For sql_base.cc look at close_data_tables().
+*/
+
+int ha_partition::close(void)
+{
+  bool first= TRUE;
+  handler **file;
+  uint i;
+  st_partition_ft_info *tmp_ft_info;
+  DBUG_ENTER("ha_partition::close");
+  DBUG_ASSERT(table->s == table_share);
+  DBUG_ASSERT(m_part_info);
+
+  destroy_record_priority_queue();
+
+  for (; ft_first ; ft_first= tmp_ft_info)
+  {
+    tmp_ft_info= ft_first->next;
+    my_free(ft_first);
+  }
+
+  /* Free active mrr_ranges */
+  for (i= 0; i < m_tot_parts; i++)
+  {
+    if (m_part_mrr_range_first[i])
+    {
+      PARTITION_PART_KEY_MULTI_RANGE *tmp_mrr_range_first=
+        m_part_mrr_range_first[i];
+      do
+      {
+        PARTITION_PART_KEY_MULTI_RANGE *tmp_mrr_range_current;
+        tmp_mrr_range_current= tmp_mrr_range_first;
+        tmp_mrr_range_first= tmp_mrr_range_first->next;
+        my_free(tmp_mrr_range_current);
+      } while (tmp_mrr_range_first);
+    }
+  }
+  if (m_mrr_range_first)
+  {
+    do
+    {
+      m_mrr_range_current= m_mrr_range_first;
+      m_mrr_range_first= m_mrr_range_first->next;
+      if (m_mrr_range_current->key[0])
+        my_free(m_mrr_range_current->key[0]);
+      if (m_mrr_range_current->key[1])
+        my_free(m_mrr_range_current->key[1]);
+      my_free(m_mrr_range_current);
+    } while (m_mrr_range_first);
+  }
+  my_free(m_range_info);
+  m_range_info= NULL;                           // Safety
+
+  if (m_mrr_full_buffer)
+  {
+    my_free(m_mrr_full_buffer);
+    m_mrr_full_buffer= NULL;
+    m_mrr_full_buffer_size= 0;
+  }
+  file= m_file;
+
+repeat:
+  do
+  {
+    if (!first || bitmap_is_set(&m_opened_partitions, (uint)(file - m_file)))
+      (*file)->ha_close();
+  } while (*(++file));
+
+  free_partition_bitmaps();
+
+  if (first && m_added_file && m_added_file[0])
+  {
+    file= m_added_file;
+    first= FALSE;
+    goto repeat;
+  }
+
+  m_handler_status= handler_closed;
+  DBUG_RETURN(0);
+}
+
+/****************************************************************************
+                MODULE start/end statement
+****************************************************************************/
+/*
+  A number of methods to define various constants for the handler. In
+  the case of the partition handler we need to use some max and min
+  of the underlying handlers in most cases.
+*/
+
+/*
+  Set external locks on table
+
+  SYNOPSIS
+    external_lock()
+    thd                    Thread object
+    lock_type              Type of external lock
+
+  RETURN VALUE
+    >0                   Error code
+    0                    Success
+
+  DESCRIPTION
+    First you should go read the section "locking functions for mysql" in
+    lock.cc to understand this.
+    This create a lock on the table. If you are implementing a storage engine
+    that can handle transactions look at ha_berkeley.cc to see how you will
+    want to go about doing this. Otherwise you should consider calling
+    flock() here.
+    Originally this method was used to set locks on file level to enable
+    several MySQL Servers to work on the same data. For transactional
+    engines it has been "abused" to also mean start and end of statements
+    to enable proper rollback of statements and transactions. When LOCK
+    TABLES has been issued the start_stmt method takes over the role of
+    indicating start of statement but in this case there is no end of
+    statement indicator(?).
+
+    Called from lock.cc by lock_external() and unlock_external(). Also called
+    from sql_table.cc by copy_data_between_tables().
+*/
+
+int ha_partition::external_lock(THD *thd, int lock_type)
+{
+  int error;
+  uint i, first_used_partition;
+  MY_BITMAP *used_partitions;
+  DBUG_ENTER("ha_partition::external_lock");
+
+  DBUG_ASSERT(!auto_increment_lock);
+  DBUG_ASSERT(!auto_increment_safe_stmt_log_lock);
+
+  if (lock_type == F_UNLCK)
+    used_partitions= &m_locked_partitions;
+  else
+    used_partitions= &(m_part_info->lock_partitions);
+
+  first_used_partition= bitmap_get_first_set(used_partitions);
+
+  for (i= first_used_partition;
+       i < m_tot_parts;
+       i= bitmap_get_next_set(used_partitions, i))
+  {
+    DBUG_PRINT("info", ("external_lock(thd, %d) part %u", lock_type, i));
+    if (unlikely((error= m_file[i]->ha_external_lock(thd, lock_type))))
+    {
+      if (lock_type != F_UNLCK)
+        goto err_handler;
+    }
+    DBUG_PRINT("info", ("external_lock part %u lock %d", i, lock_type));
+    if (lock_type != F_UNLCK)
+      bitmap_set_bit(&m_locked_partitions, i);
+  }
+  if (lock_type == F_UNLCK)
+  {
+    bitmap_clear_all(used_partitions);
+  }
+  else
+  {
+    /* Add touched partitions to be included in reset(). */
+    bitmap_union(&m_partitions_to_reset, used_partitions);
+  }
+
+  if (m_added_file && m_added_file[0])
+  {
+    handler **file= m_added_file;
+    DBUG_ASSERT(lock_type == F_UNLCK);
+    do
+    {
+      (void) (*file)->ha_external_lock(thd, lock_type);
+    } while (*(++file));
+  }
+  if (lock_type == F_WRLCK)
+  {
+    if (m_part_info->part_expr)
+      m_part_info->part_expr->walk(&Item::register_field_in_read_map, 1, 0);
+    if (m_part_info->part_type == VERSIONING_PARTITION &&
+      /* TODO: MDEV-20345 exclude more inapproriate commands like INSERT
+         These commands may be excluded because working history partition is needed
+         only for versioned DML. */
+      thd->lex->sql_command != SQLCOM_SELECT &&
+      thd->lex->sql_command != SQLCOM_INSERT_SELECT)
+      m_part_info->vers_set_hist_part(thd);
+  }
+  DBUG_RETURN(0);
+
+err_handler:
+  uint j;
+  for (j= first_used_partition;
+       j < i;
+       j= bitmap_get_next_set(&m_locked_partitions, j))
+  {
+    (void) m_file[j]->ha_external_unlock(thd);
+  }
+  bitmap_clear_all(&m_locked_partitions);
+  DBUG_RETURN(error);
+}
+
+
+/*
+  Get the lock(s) for the table and perform conversion of locks if needed
+
+  SYNOPSIS
+    store_lock()
+    thd                   Thread object
+    to                    Lock object array
+    lock_type             Table lock type
+
+  RETURN VALUE
+    >0                   Error code
+    0                    Success
+
+  DESCRIPTION
+    The idea with handler::store_lock() is the following:
+
+    The statement decided which locks we should need for the table
+    for updates/deletes/inserts we get WRITE locks, for SELECT... we get
+    read locks.
+
+    Before adding the lock into the table lock handler (see thr_lock.c)
+    mysqld calls store lock with the requested locks.  Store lock can now
+    modify a write lock to a read lock (or some other lock), ignore the
+    lock (if we don't want to use MySQL table locks at all) or add locks
+    for many tables (like we do when we are using a MERGE handler).
+
+    Berkeley DB for partition  changes all WRITE locks to TL_WRITE_ALLOW_WRITE
+    (which signals that we are doing WRITES, but we are still allowing other
+    reader's and writer's.
+
+    When releasing locks, store_lock() is also called. In this case one
+    usually doesn't have to do anything.
+
+    store_lock is called when holding a global mutex to ensure that only
+    one thread at a time changes the locking information of tables.
+
+    In some exceptional cases MySQL may send a request for a TL_IGNORE;
+    This means that we are requesting the same lock as last time and this
+    should also be ignored. (This may happen when someone does a flush
+    table when we have opened a part of the tables, in which case mysqld
+    closes and reopens the tables and tries to get the same locks as last
+    time).  In the future we will probably try to remove this.
+
+    Called from lock.cc by get_lock_data().
+*/
+
+THR_LOCK_DATA **ha_partition::store_lock(THD *thd,
+					 THR_LOCK_DATA **to,
+					 enum thr_lock_type lock_type)
+{
+  uint i;
+  DBUG_ENTER("ha_partition::store_lock");
+  DBUG_ASSERT(thd == current_thd);
+
+  /*
+    This can be called from get_lock_data() in mysql_lock_abort_for_thread(),
+    even when thd != table->in_use. In that case don't use partition pruning,
+    but use all partitions instead to avoid using another threads structures.
+  */
+  if (thd != table->in_use)
+  {
+    for (i= 0; i < m_tot_parts; i++)
+      to= m_file[i]->store_lock(thd, to, lock_type);
+  }
+  else
+  {
+    MY_BITMAP *used_partitions= lock_type == TL_UNLOCK ||
+                                lock_type == TL_IGNORE ?
+                                &m_locked_partitions :
+                                &m_part_info->lock_partitions;
+
+    for (i= bitmap_get_first_set(used_partitions);
+         i < m_tot_parts;
+         i= bitmap_get_next_set(used_partitions, i))
+    {
+      DBUG_PRINT("info", ("store lock %u iteration", i));
+      to= m_file[i]->store_lock(thd, to, lock_type);
+    }
+  }
+  DBUG_RETURN(to);
+}
+
+/*
+  Start a statement when table is locked
+
+  SYNOPSIS
+    start_stmt()
+    thd                  Thread object
+    lock_type            Type of external lock
+
+  RETURN VALUE
+    >0                   Error code
+    0                    Success
+
+  DESCRIPTION
+    This method is called instead of external lock when the table is locked
+    before the statement is executed.
+*/
+
+int ha_partition::start_stmt(THD *thd, thr_lock_type lock_type)
+{
+  int error= 0;
+  uint i;
+  /* Assert that read_partitions is included in lock_partitions */
+  DBUG_ASSERT(bitmap_is_subset(&m_part_info->read_partitions,
+                               &m_part_info->lock_partitions));
+  /*
+    m_locked_partitions is set in previous external_lock/LOCK TABLES.
+    Current statement's lock requests must not include any partitions
+    not previously locked.
+  */
+  DBUG_ASSERT(bitmap_is_subset(&m_part_info->lock_partitions,
+                               &m_locked_partitions));
+  DBUG_ENTER("ha_partition::start_stmt");
+
+  for (i= bitmap_get_first_set(&(m_part_info->lock_partitions));
+       i < m_tot_parts;
+       i= bitmap_get_next_set(&m_part_info->lock_partitions, i))
+  {
+    if (unlikely((error= m_file[i]->start_stmt(thd, lock_type))))
+      break;
+    /* Add partition to be called in reset(). */
+    bitmap_set_bit(&m_partitions_to_reset, i);
+  }
+  switch (lock_type)
+  {
+  case TL_WRITE_ALLOW_WRITE:
+  case TL_WRITE_CONCURRENT_INSERT:
+  case TL_WRITE_DELAYED:
+  case TL_WRITE_DEFAULT:
+  case TL_WRITE_LOW_PRIORITY:
+  case TL_WRITE:
+  case TL_WRITE_ONLY:
+    if (m_part_info->part_expr)
+      m_part_info->part_expr->walk(&Item::register_field_in_read_map, 1, 0);
+    if (m_part_info->part_type == VERSIONING_PARTITION &&
+      // TODO: MDEV-20345 (see above)
+      thd->lex->sql_command != SQLCOM_SELECT &&
+      thd->lex->sql_command != SQLCOM_INSERT_SELECT)
+      m_part_info->vers_set_hist_part(thd);
+  default:;
+  }
+  DBUG_RETURN(error);
+}
+
+
+/**
+  Get number of lock objects returned in store_lock
+
+  @returns Number of locks returned in call to store_lock
+
+  @desc
+    Returns the maxinum possible number of store locks needed in call to
+    store lock.
+*/
+
+uint ha_partition::lock_count() const
+{
+  DBUG_ENTER("ha_partition::lock_count");
+  DBUG_RETURN(m_num_locks);
+}
+
+
+/*
+  Unlock last accessed row
+
+  SYNOPSIS
+    unlock_row()
+
+  RETURN VALUE
+    NONE
+
+  DESCRIPTION
+    Record currently processed was not in the result set of the statement
+    and is thus unlocked. Used for UPDATE and DELETE queries.
+*/
+
+void ha_partition::unlock_row()
+{
+  DBUG_ENTER("ha_partition::unlock_row");
+  m_file[m_last_part]->unlock_row();
+  DBUG_VOID_RETURN;
+}
+
+/**
+  Check if semi consistent read was used
+
+  SYNOPSIS
+    was_semi_consistent_read()
+
+  RETURN VALUE
+    TRUE   Previous read was a semi consistent read
+    FALSE  Previous read was not a semi consistent read
+
+  DESCRIPTION
+    See handler.h:
+    In an UPDATE or DELETE, if the row under the cursor was locked by another
+    transaction, and the engine used an optimistic read of the last
+    committed row value under the cursor, then the engine returns 1 from this
+    function. MySQL must NOT try to update this optimistic value. If the
+    optimistic value does not match the WHERE condition, MySQL can decide to
+    skip over this row. Currently only works for InnoDB. This can be used to
+    avoid unnecessary lock waits.
+
+    If this method returns nonzero, it will also signal the storage
+    engine that the next read will be a locking re-read of the row.
+*/
+bool ha_partition::was_semi_consistent_read()
+{
+  DBUG_ENTER("ha_partition::was_semi_consistent_read");
+  DBUG_ASSERT(m_last_part < m_tot_parts);
+  DBUG_ASSERT(bitmap_is_set(&(m_part_info->read_partitions), m_last_part));
+  DBUG_RETURN(m_file[m_last_part]->was_semi_consistent_read());
+}
+
+/**
+  Use semi consistent read if possible
+
+  SYNOPSIS
+    try_semi_consistent_read()
+    yes   Turn on semi consistent read
+
+  RETURN VALUE
+    NONE
+
+  DESCRIPTION
+    See handler.h:
+    Tell the engine whether it should avoid unnecessary lock waits.
+    If yes, in an UPDATE or DELETE, if the row under the cursor was locked
+    by another transaction, the engine may try an optimistic read of
+    the last committed row value under the cursor.
+    Note: prune_partitions are already called before this call, so using
+    pruning is OK.
+*/
+void ha_partition::try_semi_consistent_read(bool yes)
+{
+  uint i;
+  DBUG_ENTER("ha_partition::try_semi_consistent_read");
+
+  i= bitmap_get_first_set(&(m_part_info->read_partitions));
+  DBUG_ASSERT(i != MY_BIT_NONE);
+  for (;
+       i < m_tot_parts;
+       i= bitmap_get_next_set(&m_part_info->read_partitions, i))
+  {
+    m_file[i]->try_semi_consistent_read(yes);
+  }
+  DBUG_VOID_RETURN;
+}
+
+
+/****************************************************************************
+                MODULE change record
+****************************************************************************/
+
+/*
+  Insert a row to the table
+
+  SYNOPSIS
+    write_row()
+    buf                        The row in MySQL Row Format
+
+  RETURN VALUE
+    >0                         Error code
+    0                          Success
+
+  DESCRIPTION
+    write_row() inserts a row. buf() is a byte array of data, normally
+    record[0].
+
+    You can use the field information to extract the data from the native byte
+    array type.
+
+    Example of this would be:
+    for (Field **field=table->field ; *field ; field++)
+    {
+      ...
+    }
+
+    See ha_tina.cc for a variant of extracting all of the data as strings.
+    ha_berkeley.cc has a variant of how to store it intact by "packing" it
+    for ha_berkeley's own native storage type.
+
+    Called from item_sum.cc, item_sum.cc, sql_acl.cc, sql_insert.cc,
+    sql_insert.cc, sql_select.cc, sql_table.cc, sql_udf.cc, and sql_update.cc.
+
+    ADDITIONAL INFO:
+
+    We have to set auto_increment fields, because those may be used in
+    determining which partition the row should be written to.
+*/
+
+int ha_partition::write_row(const uchar * buf)
+{
+  uint32 part_id;
+  int error;
+  longlong func_value;
+  bool have_auto_increment= table->next_number_field && buf == table->record[0];
+  MY_BITMAP *old_map;
+  THD *thd= ha_thd();
+  Sql_mode_save sms(thd);
+  bool saved_auto_inc_field_not_null= table->auto_increment_field_not_null;
+  DBUG_ENTER("ha_partition::write_row");
+  DBUG_PRINT("enter", ("partition this: %p", this));
+
+  /*
+    If we have an auto_increment column and we are writing a changed row
+    or a new row, then update the auto_increment value in the record.
+  */
+  if (have_auto_increment)
+  {
+    if (!table_share->next_number_keypart)
+      update_next_auto_inc_val();
+    error= update_auto_increment();
+
+    /*
+      If we have failed to set the auto-increment value for this row,
+      it is highly likely that we will not be able to insert it into
+      the correct partition. We must check and fail if necessary.
+    */
+    if (unlikely(error))
+      goto exit;
+
+    /*
+      Don't allow generation of auto_increment value the partitions handler.
+      If a partitions handler would change the value, then it might not
+      match the partition any longer.
+      This can occur if 'SET INSERT_ID = 0; INSERT (NULL)',
+      So allow this by adding 'MODE_NO_AUTO_VALUE_ON_ZERO' to sql_mode.
+      The partitions handler::next_insert_id must always be 0. Otherwise
+      we need to forward release_auto_increment, or reset it for all
+      partitions.
+    */
+    if (table->next_number_field->val_int() == 0)
+    {
+      table->auto_increment_field_not_null= TRUE;
+      thd->variables.sql_mode|= MODE_NO_AUTO_VALUE_ON_ZERO;
+    }
+  }
+  old_map= dbug_tmp_use_all_columns(table, &table->read_set);
+  error= m_part_info->get_partition_id(m_part_info, &part_id, &func_value);
+  dbug_tmp_restore_column_map(&table->read_set, old_map);
+  if (unlikely(error))
+  {
+    m_part_info->err_value= func_value;
+    goto exit;
+  }
+  if (!bitmap_is_set(&(m_part_info->lock_partitions), part_id))
+  {
+    DBUG_PRINT("info", ("Write to non-locked partition %u (func_value: %ld)",
+                        part_id, (long) func_value));
+    error= HA_ERR_NOT_IN_LOCK_PARTITIONS;
+    goto exit;
+  }
+  m_last_part= part_id;
+  DBUG_PRINT("info", ("Insert in partition %u", part_id));
+
+  start_part_bulk_insert(thd, part_id);
+
+  DBUG_ASSERT(!m_file[part_id]->row_logging);
+  error= m_file[part_id]->ha_write_row(buf);
+  if (!error && have_auto_increment && !table->s->next_number_keypart)
+    set_auto_increment_if_higher(table->next_number_field);
+
+exit:
+  table->auto_increment_field_not_null= saved_auto_inc_field_not_null;
+  DBUG_RETURN(error);
+}
+
+
+/*
+  Update an existing row
+
+  SYNOPSIS
+    update_row()
+    old_data                 Old record in MySQL Row Format
+    new_data                 New record in MySQL Row Format
+
+  RETURN VALUE
+    >0                         Error code
+    0                          Success
+
+  DESCRIPTION
+    Yes, update_row() does what you expect, it updates a row. old_data will
+    have the previous row record in it, while new_data will have the newest
+    data in it.
+    Keep in mind that the server can do updates based on ordering if an
+    ORDER BY clause was used. Consecutive ordering is not guaranteed.
+
+    Called from sql_select.cc, sql_acl.cc, sql_update.cc, and sql_insert.cc.
+    new_data is always record[0]
+    old_data is always record[1]
+*/
+
+int ha_partition::update_row(const uchar *old_data, const uchar *new_data)
+{
+  THD *thd= ha_thd();
+  uint32 new_part_id, old_part_id= m_last_part;
+  int error= 0;
+  DBUG_ENTER("ha_partition::update_row");
+  m_err_rec= NULL;
+
+  // Need to read partition-related columns, to locate the row's partition:
+  DBUG_ASSERT(bitmap_is_subset(&m_part_info->full_part_field_set,
+                               table->read_set));
+#ifndef DBUG_OFF
+  /*
+    The protocol for updating a row is:
+    1) position the handler (cursor) on the row to be updated,
+       either through the last read row (rnd or index) or by rnd_pos.
+    2) call update_row with both old and new full records as arguments.
+
+    This means that m_last_part should already be set to actual partition
+    where the row was read from. And if that is not the same as the
+    calculated part_id we found a misplaced row, we return an error to
+    notify the user that something is broken in the row distribution
+    between partitions! Since we don't check all rows on read, we return an
+    error instead of correcting m_last_part, to make the user aware of the
+    problem!
+
+    Notice that HA_READ_BEFORE_WRITE_REMOVAL does not require this protocol,
+    so this is not supported for this engine.
+  */
+  error= get_part_for_buf(old_data, m_rec0, m_part_info, &old_part_id);
+  DBUG_ASSERT(!error);
+  DBUG_ASSERT(old_part_id == m_last_part);
+  DBUG_ASSERT(bitmap_is_set(&(m_part_info->read_partitions), old_part_id));
+#endif
+
+  if (unlikely((error= get_part_for_buf(new_data, m_rec0, m_part_info,
+                                        &new_part_id))))
+    goto exit;
+  if (unlikely(!bitmap_is_set(&(m_part_info->lock_partitions), new_part_id)))
+  {
+    error= HA_ERR_NOT_IN_LOCK_PARTITIONS;
+    goto exit;
+  }
+
+
+  m_last_part= new_part_id;
+  start_part_bulk_insert(thd, new_part_id);
+  DBUG_ASSERT(!m_file[new_part_id]->row_logging);
+  if (new_part_id == old_part_id)
+  {
+    DBUG_PRINT("info", ("Update in partition %u", (uint) new_part_id));
+    error= m_file[new_part_id]->ha_update_row(old_data, new_data);
+    goto exit;
+  }
+  else
+  {
+    Field *saved_next_number_field= table->next_number_field;
+    /*
+      Don't allow generation of auto_increment value for update.
+      table->next_number_field is never set on UPDATE.
+      But is set for INSERT ... ON DUPLICATE KEY UPDATE,
+      and since update_row() does not generate or update an auto_inc value,
+      we cannot have next_number_field set when moving a row
+      to another partition with write_row(), since that could
+      generate/update the auto_inc value.
+      This gives the same behavior for partitioned vs non partitioned tables.
+    */
+    table->next_number_field= NULL;
+    DBUG_PRINT("info", ("Update from partition %u to partition %u",
+			(uint) old_part_id, (uint) new_part_id));
+    error= m_file[new_part_id]->ha_write_row((uchar*) new_data);
+    table->next_number_field= saved_next_number_field;
+    if (unlikely(error))
+      goto exit;
+
+    error= m_file[old_part_id]->ha_delete_row(old_data);
+    if (unlikely(error))
+      goto exit;
+  }
+
+exit:
+  /*
+    if updating an auto_increment column, update
+    part_share->next_auto_inc_val if needed.
+    (not to be used if auto_increment on secondary field in a multi-column
+    index)
+    mysql_update does not set table->next_number_field, so we use
+    table->found_next_number_field instead.
+    Also checking that the field is marked in the write set.
+  */
+  if (table->found_next_number_field &&
+      new_data == table->record[0] &&
+      !table->s->next_number_keypart &&
+      bitmap_is_set(table->write_set,
+                    table->found_next_number_field->field_index))
+  {
+    update_next_auto_inc_val();
+    if (part_share->auto_inc_initialized)
+      set_auto_increment_if_higher(table->found_next_number_field);
+  }
+  DBUG_RETURN(error);
+}
+
+
+/*
+  Remove an existing row
+
+  SYNOPSIS
+    delete_row
+    buf                      Deleted row in MySQL Row Format
+
+  RETURN VALUE
+    >0                       Error Code
+    0                        Success
+
+  DESCRIPTION
+    This will delete a row. buf will contain a copy of the row to be deleted.
+    The server will call this right after the current row has been read
+    (from either a previous rnd_xxx() or index_xxx() call).
+    If you keep a pointer to the last row or can access a primary key it will
+    make doing the deletion quite a bit easier.
+    Keep in mind that the server does no guarantee consecutive deletions.
+    ORDER BY clauses can be used.
+
+    Called in sql_acl.cc and sql_udf.cc to manage internal table information.
+    Called in sql_delete.cc, sql_insert.cc, and sql_select.cc. In sql_select
+    it is used for removing duplicates while in insert it is used for REPLACE
+    calls.
+
+    buf is either record[0] or record[1]
+*/
+
+int ha_partition::delete_row(const uchar *buf)
+{
+  int error;
+  DBUG_ENTER("ha_partition::delete_row");
+  m_err_rec= NULL;
+
+  DBUG_ASSERT(bitmap_is_subset(&m_part_info->full_part_field_set,
+                               table->read_set));
+#ifndef DBUG_OFF
+  THD* thd = ha_thd();
+  /*
+    The protocol for deleting a row is:
+    1) position the handler (cursor) on the row to be deleted,
+       either through the last read row (rnd or index) or by rnd_pos.
+    2) call delete_row with the full record as argument.
+
+    This means that m_last_part should already be set to actual partition
+    where the row was read from. And if that is not the same as the
+    calculated part_id we found a misplaced row, we return an error to
+    notify the user that something is broken in the row distribution
+    between partitions! Since we don't check all rows on read, we return an
+    error instead of forwarding the delete to the correct (m_last_part)
+    partition!
+
+    Notice that HA_READ_BEFORE_WRITE_REMOVAL does not require this protocol,
+    so this is not supported for this engine.
+
+    For partitions by system_time, get_part_for_buf() is always either current
+    or last historical partition, but DELETE HISTORY can delete from any
+    historical partition. So, skip the check in this case.
+  */
+  if (!thd->lex->vers_conditions.delete_history)
+  {
+    uint32 part_id;
+    error= get_part_for_buf(buf, m_rec0, m_part_info, &part_id);
+    DBUG_ASSERT(!error);
+    DBUG_ASSERT(part_id == m_last_part);
+  }
+  DBUG_ASSERT(bitmap_is_set(&(m_part_info->read_partitions), m_last_part));
+  DBUG_ASSERT(bitmap_is_set(&(m_part_info->lock_partitions), m_last_part));
+#endif
+
+  if (!bitmap_is_set(&(m_part_info->lock_partitions), m_last_part))
+    DBUG_RETURN(HA_ERR_NOT_IN_LOCK_PARTITIONS);
+
+  DBUG_ASSERT(!m_file[m_last_part]->row_logging);
+  error= m_file[m_last_part]->ha_delete_row(buf);
+  DBUG_RETURN(error);
+}
+
+
+/*
+  Delete all rows in a table
+
+  SYNOPSIS
+    delete_all_rows()
+
+  RETURN VALUE
+    >0                       Error Code
+    0                        Success
+
+  DESCRIPTION
+    Used to delete all rows in a table. Both for cases of truncate and
+    for cases where the optimizer realizes that all rows will be
+    removed as a result of a SQL statement.
+
+    Called from item_sum.cc by Item_func_group_concat::clear(),
+    Item_sum_count::clear(), and Item_func_group_concat::clear().
+    Called from sql_delete.cc by mysql_delete().
+    Called from sql_select.cc by JOIN::reset().
+    Called from sql_union.cc by st_select_lex_unit::exec().
+*/
+
+int ha_partition::delete_all_rows()
+{
+  int error;
+  uint i;
+  DBUG_ENTER("ha_partition::delete_all_rows");
+
+  for (i= bitmap_get_first_set(&m_part_info->read_partitions);
+       i < m_tot_parts;
+       i= bitmap_get_next_set(&m_part_info->read_partitions, i))
+  {
+    /* Can be pruned, like DELETE FROM t PARTITION (pX) */
+    if (unlikely((error= m_file[i]->ha_delete_all_rows())))
+      DBUG_RETURN(error);
+  }
+  DBUG_RETURN(0);
+}
+
+
+/**
+  Manually truncate the table.
+
+  @retval  0    Success.
+  @retval  > 0  Error code.
+*/
+
+int ha_partition::truncate()
+{
+  int error;
+  handler **file;
+  DBUG_ENTER("ha_partition::truncate");
+
+  /*
+    TRUNCATE also means resetting auto_increment. Hence, reset
+    it so that it will be initialized again at the next use.
+  */
+  lock_auto_increment();
+  part_share->next_auto_inc_val= 0;
+  part_share->auto_inc_initialized= false;
+  unlock_auto_increment();
+
+  file= m_file;
+  do
+  {
+    if (unlikely((error= (*file)->ha_truncate())))
+      DBUG_RETURN(error);
+  } while (*(++file));
+  DBUG_RETURN(0);
+}
+
+
+/**
+  Truncate a set of specific partitions.
+
+  @remark Auto increment value will be truncated in that partition as well!
+
+  ALTER TABLE t TRUNCATE PARTITION ...
+*/
+
+int ha_partition::truncate_partition(Alter_info *alter_info, bool *binlog_stmt)
+{
+  int error= 0;
+  List_iterator<partition_element> part_it(m_part_info->partitions);
+  uint num_parts= m_part_info->num_parts;
+  uint num_subparts= m_part_info->num_subparts;
+  uint i= 0;
+  DBUG_ENTER("ha_partition::truncate_partition");
+
+  /* Only binlog when it starts any call to the partitions handlers */
+  *binlog_stmt= false;
+
+  if (set_part_state(alter_info, m_part_info, PART_ADMIN))
+    DBUG_RETURN(HA_ERR_NO_PARTITION_FOUND);
+
+  /*
+    TRUNCATE also means resetting auto_increment. Hence, reset
+    it so that it will be initialized again at the next use.
+  */
+  lock_auto_increment();
+  part_share->next_auto_inc_val= 0;
+  part_share->auto_inc_initialized= FALSE;
+  unlock_auto_increment();
+
+  *binlog_stmt= true;
+
+  do
+  {
+    partition_element *part_elem= part_it++;
+    if (part_elem->part_state == PART_ADMIN)
+    {
+      if (m_is_sub_partitioned)
+      {
+        List_iterator<partition_element>
+                                    subpart_it(part_elem->subpartitions);
+        partition_element *sub_elem;
+        uint j= 0, part;
+        do
+        {
+          sub_elem= subpart_it++;
+          part= i * num_subparts + j;
+          DBUG_PRINT("info", ("truncate subpartition %u (%s)",
+                              part, sub_elem->partition_name));
+          if (unlikely((error= m_file[part]->ha_truncate())))
+            break;
+          sub_elem->part_state= PART_NORMAL;
+        } while (++j < num_subparts);
+      }
+      else
+      {
+        DBUG_PRINT("info", ("truncate partition %u (%s)", i,
+                            part_elem->partition_name));
+        error= m_file[i]->ha_truncate();
+      }
+      part_elem->part_state= PART_NORMAL;
+    }
+  } while (!error && (++i < num_parts));
+  DBUG_RETURN(error);
+}
+
+
+/*
+  Start a large batch of insert rows
+
+  SYNOPSIS
+    start_bulk_insert()
+    rows                  Number of rows to insert
+    flags                 Flags to control index creation
+
+  RETURN VALUE
+    NONE
+
+  DESCRIPTION
+    rows == 0 means we will probably insert many rows
+*/
+void ha_partition::start_bulk_insert(ha_rows rows, uint flags)
+{
+  DBUG_ENTER("ha_partition::start_bulk_insert");
+
+  m_bulk_inserted_rows= 0;
+  bitmap_clear_all(&m_bulk_insert_started);
+  /* use the last bit for marking if bulk_insert_started was called */
+  bitmap_set_bit(&m_bulk_insert_started, m_tot_parts);
+  DBUG_VOID_RETURN;
+}
+
+
+/*
+  Check if start_bulk_insert has been called for this partition,
+  if not, call it and mark it called
+*/
+void ha_partition::start_part_bulk_insert(THD *thd, uint part_id)
+{
+  long old_buffer_size;
+  if (!bitmap_is_set(&m_bulk_insert_started, part_id) &&
+      bitmap_is_set(&m_bulk_insert_started, m_tot_parts))
+  {
+    DBUG_ASSERT(bitmap_is_set(&(m_part_info->lock_partitions), part_id));
+    old_buffer_size= thd->variables.read_buff_size;
+    /* Update read_buffer_size for this partition */
+    thd->variables.read_buff_size= estimate_read_buffer_size(old_buffer_size);
+    m_file[part_id]->ha_start_bulk_insert(guess_bulk_insert_rows());
+    bitmap_set_bit(&m_bulk_insert_started, part_id);
+    thd->variables.read_buff_size= old_buffer_size;
+  }
+  m_bulk_inserted_rows++;
+}
+
+/*
+  Estimate the read buffer size for each partition.
+  SYNOPSIS
+    ha_partition::estimate_read_buffer_size()
+    original_size  read buffer size originally set for the server
+  RETURN VALUE
+    estimated buffer size.
+  DESCRIPTION
+    If the estimated number of rows to insert is less than 10 (but not 0)
+    the new buffer size is same as original buffer size.
+    In case of first partition of when partition function is monotonic
+    new buffer size is same as the original buffer size.
+    For rest of the partition total buffer of 10*original_size is divided
+    equally if number of partition is more than 10 other wise each partition
+    will be allowed to use original buffer size.
+*/
+long ha_partition::estimate_read_buffer_size(long original_size)
+{
+  /*
+    If number of rows to insert is less than 10, but not 0,
+    return original buffer size.
+  */
+  if (estimation_rows_to_insert && (estimation_rows_to_insert < 10))
+    return (original_size);
+  /*
+    If first insert/partition and monotonic partition function,
+    allow using buffer size originally set.
+   */
+  if (!m_bulk_inserted_rows &&
+      m_part_func_monotonicity_info != NON_MONOTONIC &&
+      m_tot_parts > 1)
+    return original_size;
+  /*
+    Allow total buffer used in all partition to go up to 10*read_buffer_size.
+    11*read_buffer_size in case of monotonic partition function.
+  */
+
+  if (m_tot_parts < 10)
+      return original_size;
+  return (original_size * 10 / m_tot_parts);
+}
+
+/*
+  Try to predict the number of inserts into this partition.
+
+  If less than 10 rows (including 0 which means Unknown)
+    just give that as a guess
+  If monotonic partitioning function was used
+    guess that 50 % of the inserts goes to the first partition
+  For all other cases, guess on equal distribution between the partitions
+*/
+ha_rows ha_partition::guess_bulk_insert_rows()
+{
+  DBUG_ENTER("guess_bulk_insert_rows");
+
+  if (estimation_rows_to_insert < 10)
+    DBUG_RETURN(estimation_rows_to_insert);
+
+  /* If first insert/partition and monotonic partition function, guess 50%.  */
+  if (!m_bulk_inserted_rows &&
+      m_part_func_monotonicity_info != NON_MONOTONIC &&
+      m_tot_parts > 1)
+    DBUG_RETURN(estimation_rows_to_insert / 2);
+
+  /* Else guess on equal distribution (+1 is to avoid returning 0/Unknown) */
+  if (m_bulk_inserted_rows < estimation_rows_to_insert)
+    DBUG_RETURN(((estimation_rows_to_insert - m_bulk_inserted_rows)
+                / m_tot_parts) + 1);
+  /* The estimation was wrong, must say 'Unknown' */
+  DBUG_RETURN(0);
+}
+
+
+void ha_partition::sum_copy_info(handler *file)
+{
+  copy_info.records+= file->copy_info.records;
+  copy_info.touched+= file->copy_info.touched;
+  copy_info.copied+=  file->copy_info.copied;
+  copy_info.deleted+= file->copy_info.deleted;
+  copy_info.updated+= file->copy_info.updated;
+}
+
+
+void ha_partition::sum_copy_infos()
+{
+  handler **file_array;
+  bzero(&copy_info, sizeof(copy_info));
+  file_array= m_file;
+  do
+  {
+    if (bitmap_is_set(&(m_opened_partitions), (uint)(file_array - m_file)))
+      sum_copy_info(*file_array);
+  } while (*(++file_array));
+}
+
+void ha_partition::reset_copy_info()
+{
+  handler **file_array;
+  bzero(&copy_info, sizeof(copy_info));
+  file_array= m_file;
+  do
+  {
+    if (bitmap_is_set(&(m_opened_partitions), (uint)(file_array - m_file)))
+      bzero(&(*file_array)->copy_info, sizeof(copy_info));
+  } while (*(++file_array));
+}
+
+
+
+/*
+  Finish a large batch of insert rows
+
+  SYNOPSIS
+    end_bulk_insert()
+
+  RETURN VALUE
+    >0                      Error code
+    0                       Success
+
+  Note: end_bulk_insert can be called without start_bulk_insert
+        being called, see bug#44108.
+
+*/
+
+int ha_partition::end_bulk_insert()
+{
+  int error= 0;
+  uint i;
+  DBUG_ENTER("ha_partition::end_bulk_insert");
+
+  if (!bitmap_is_set(&m_bulk_insert_started, m_tot_parts))
+    DBUG_RETURN(error);
+
+  for (i= bitmap_get_first_set(&m_bulk_insert_started);
+       i < m_tot_parts;
+       i= bitmap_get_next_set(&m_bulk_insert_started, i))
+  {
+    int tmp;
+    if ((tmp= m_file[i]->ha_end_bulk_insert()))
+      error= tmp;
+    sum_copy_info(m_file[i]);
+  }
+  bitmap_clear_all(&m_bulk_insert_started);
+  DBUG_RETURN(error);
+}
+
+
+/****************************************************************************
+                MODULE full table scan
+****************************************************************************/
+/*
+  Initialize engine for random reads
+
+  SYNOPSIS
+    ha_partition::rnd_init()
+    scan	0  Initialize for random reads through rnd_pos()
+		1  Initialize for random scan through rnd_next()
+
+  RETURN VALUE
+    >0          Error code
+    0           Success
+
+  DESCRIPTION
+    rnd_init() is called when the server wants the storage engine to do a
+    table scan or when the server wants to access data through rnd_pos.
+
+    When scan is used we will scan one handler partition at a time.
+    When preparing for rnd_pos we will init all handler partitions.
+    No extra cache handling is needed when scanning is not performed.
+
+    Before initialising we will call rnd_end to ensure that we clean up from
+    any previous incarnation of a table scan.
+    Called from filesort.cc, records.cc, sql_handler.cc, sql_select.cc,
+    sql_table.cc, and sql_update.cc.
+*/
+
+int ha_partition::rnd_init(bool scan)
+{
+  int error;
+  uint i= 0;
+  uint32 part_id;
+  DBUG_ENTER("ha_partition::rnd_init");
+
+  /*
+    For operations that may need to change data, we may need to extend
+    read_set.
+  */
+  if (get_lock_type() == F_WRLCK)
+  {
+    /*
+      If write_set contains any of the fields used in partition and
+      subpartition expression, we need to set all bits in read_set because
+      the row may need to be inserted in a different [sub]partition. In
+      other words update_row() can be converted into write_row(), which
+      requires a complete record.
+    */
+    if (bitmap_is_overlapping(&m_part_info->full_part_field_set,
+                              table->write_set))
+    {
+      DBUG_PRINT("info", ("partition set full bitmap"));
+      bitmap_set_all(table->read_set);
+    }
+    else
+    {
+      /*
+        Some handlers only read fields as specified by the bitmap for the
+        read set. For partitioned handlers we always require that the
+        fields of the partition functions are read such that we can
+        calculate the partition id to place updated and deleted records.
+      */
+      DBUG_PRINT("info", ("partition set part_field bitmap"));
+      bitmap_union(table->read_set, &m_part_info->full_part_field_set);
+    }
+  }
+
+  /* Now we see what the index of our first important partition is */
+  DBUG_PRINT("info", ("m_part_info->read_partitions: %p",
+                      m_part_info->read_partitions.bitmap));
+  part_id= bitmap_get_first_set(&(m_part_info->read_partitions));
+  DBUG_PRINT("info", ("m_part_spec.start_part: %u", (uint) part_id));
+
+  if (part_id == MY_BIT_NONE)
+  {
+    error= 0;
+    goto err1;
+  }
+
+  /*
+    We have a partition and we are scanning with rnd_next
+    so we bump our cache
+  */
+  DBUG_PRINT("info", ("rnd_init on partition: %u", (uint) part_id));
+  if (scan)
+  {
+    /*
+      rnd_end() is needed for partitioning to reset internal data if scan
+      is already in use
+    */
+    rnd_end();
+    late_extra_cache(part_id);
+
+    m_index_scan_type= partition_no_index_scan;
+  }
+
+  for (i= part_id;
+       i < m_tot_parts;
+       i= bitmap_get_next_set(&m_part_info->read_partitions, i))
+  {
+    if (unlikely((error= m_file[i]->ha_rnd_init(scan))))
+      goto err;
+  }
+
+  m_scan_value= scan;
+  m_part_spec.start_part= part_id;
+  m_part_spec.end_part= m_tot_parts - 1;
+  m_rnd_init_and_first= TRUE;
+  DBUG_PRINT("info", ("m_scan_value: %u", m_scan_value));
+  DBUG_RETURN(0);
+
+err:
+  if (scan)
+    late_extra_no_cache(part_id);
+
+  /* Call rnd_end for all previously inited partitions. */
+  for (;
+       part_id < i;
+       part_id= bitmap_get_next_set(&m_part_info->read_partitions, part_id))
+  {
+    m_file[part_id]->ha_rnd_end();
+  }
+err1:
+  m_scan_value= 2;
+  m_part_spec.start_part= NO_CURRENT_PART_ID;
+  DBUG_RETURN(error);
+}
+
+
+/*
+  End of a table scan
+
+  SYNOPSIS
+    rnd_end()
+
+  RETURN VALUE
+    >0          Error code
+    0           Success
+*/
+
+int ha_partition::rnd_end()
+{
+  DBUG_ENTER("ha_partition::rnd_end");
+  switch (m_scan_value) {
+  case 2:                                       // Error
+    break;
+  case 1:                                       // Table scan
+    if (m_part_spec.start_part != NO_CURRENT_PART_ID)
+      late_extra_no_cache(m_part_spec.start_part);
+    /* fall through */
+  case 0:
+    uint i;
+    for (i= bitmap_get_first_set(&m_part_info->read_partitions);
+         i < m_tot_parts;
+         i= bitmap_get_next_set(&m_part_info->read_partitions, i))
+    {
+      m_file[i]->ha_rnd_end();
+    }
+    break;
+  }
+  m_scan_value= 2;
+  m_part_spec.start_part= NO_CURRENT_PART_ID;
+  DBUG_RETURN(0);
+}
+
+
+/*
+  read next row during full table scan (scan in random row order)
+
+  SYNOPSIS
+    rnd_next()
+    buf		buffer that should be filled with data
+
+  RETURN VALUE
+    >0          Error code
+    0           Success
+
+  DESCRIPTION
+    This is called for each row of the table scan. When you run out of records
+    you should return HA_ERR_END_OF_FILE.
+    The Field structure for the table is the key to getting data into buf
+    in a manner that will allow the server to understand it.
+
+    Called from filesort.cc, records.cc, sql_handler.cc, sql_select.cc,
+    sql_table.cc, and sql_update.cc.
+*/
+
+int ha_partition::rnd_next(uchar *buf)
+{
+  handler *file;
+  int result= HA_ERR_END_OF_FILE, error;
+  uint part_id= m_part_spec.start_part;
+  DBUG_ENTER("ha_partition::rnd_next");
+  DBUG_PRINT("enter", ("partition this: %p", this));
+
+  /* upper level will increment this once again at end of call */
+  decrement_statistics(&SSV::ha_read_rnd_next_count);
+
+  if (part_id == NO_CURRENT_PART_ID)
+  {
+    /*
+      The original set of partitions to scan was empty and thus we report
+      the result here.
+    */
+    goto end;
+  }
+
+  DBUG_ASSERT(m_scan_value == 1);
+
+  if (m_rnd_init_and_first)
+  {
+    m_rnd_init_and_first= FALSE;
+    error= handle_pre_scan(FALSE, check_parallel_search());
+    if (m_pre_calling || error)
+      DBUG_RETURN(error);
+  }
+
+  file= m_file[part_id];
+
+  while (TRUE)
+  {
+    result= file->ha_rnd_next(buf);
+    if (!result)
+    {
+      m_last_part= part_id;
+      DBUG_PRINT("info", ("partition m_last_part: %u", (uint) m_last_part));
+      m_part_spec.start_part= part_id;
+      table->status= 0;
+      DBUG_RETURN(0);
+    }
+
+    /*
+      if we get here, then the current partition ha_rnd_next returned failure
+    */
+    if (result != HA_ERR_END_OF_FILE)
+      goto end_dont_reset_start_part;         // Return error
+
+    /* End current partition */
+    late_extra_no_cache(part_id);
+    /* Shift to next partition */
+    part_id= bitmap_get_next_set(&m_part_info->read_partitions, part_id);
+    if (part_id >= m_tot_parts)
+    {
+      result= HA_ERR_END_OF_FILE;
+      break;
+    }
+    m_last_part= part_id;
+    DBUG_PRINT("info", ("partition m_last_part: %u", (uint) m_last_part));
+    m_part_spec.start_part= part_id;
+    file= m_file[part_id];
+    late_extra_cache(part_id);
+  }
+
+end:
+  DBUG_PRINT("exit", ("reset start_part"));
+  m_part_spec.start_part= NO_CURRENT_PART_ID;
+end_dont_reset_start_part:
+  DBUG_RETURN(result);
+}
+
+
+/*
+  Save position of current row
+
+  SYNOPSIS
+    position()
+    record             Current record in MySQL Row Format
+
+  RETURN VALUE
+    NONE
+
+  DESCRIPTION
+    position() is called after each call to rnd_next() if the data needs
+    to be ordered. You can do something like the following to store
+    the position:
+    ha_store_ptr(ref, ref_length, current_position);
+
+    The server uses ref to store data. ref_length in the above case is
+    the size needed to store current_position. ref is just a byte array
+    that the server will maintain. If you are using offsets to mark rows, then
+    current_position should be the offset. If it is a primary key like in
+    BDB, then it needs to be a primary key.
+
+    Called from filesort.cc, sql_select.cc, sql_delete.cc and sql_update.cc.
+*/
+
+void ha_partition::position(const uchar *record)
+{
+  handler *file= m_file[m_last_part];
+  size_t pad_length;
+  DBUG_ASSERT(bitmap_is_set(&(m_part_info->read_partitions), m_last_part));
+  DBUG_ENTER("ha_partition::position");
+
+  file->position(record);
+  int2store(ref, m_last_part);
+  memcpy((ref + PARTITION_BYTES_IN_POS), file->ref, file->ref_length);
+  pad_length= m_ref_length - PARTITION_BYTES_IN_POS - file->ref_length;
+  if (pad_length)
+    memset((ref + PARTITION_BYTES_IN_POS + file->ref_length), 0, pad_length);
+
+  DBUG_VOID_RETURN;
+}
+
+
+/*
+  Read row using position
+
+  SYNOPSIS
+    rnd_pos()
+    out:buf                     Row read in MySQL Row Format
+    position                    Position of read row
+
+  RETURN VALUE
+    >0                          Error code
+    0                           Success
+
+  DESCRIPTION
+    This is like rnd_next, but you are given a position to use
+    to determine the row. The position will be of the type that you stored in
+    ref. You can use ha_get_ptr(pos,ref_length) to retrieve whatever key
+    or position you saved when position() was called.
+    Called from filesort.cc records.cc sql_insert.cc sql_select.cc
+    sql_update.cc.
+*/
+
+int ha_partition::rnd_pos(uchar * buf, uchar *pos)
+{
+  uint part_id;
+  handler *file;
+  DBUG_ENTER("ha_partition::rnd_pos");
+  decrement_statistics(&SSV::ha_read_rnd_count);
+
+  part_id= uint2korr((const uchar *) pos);
+  DBUG_ASSERT(part_id < m_tot_parts);
+  file= m_file[part_id];
+  DBUG_ASSERT(bitmap_is_set(&(m_part_info->read_partitions), part_id));
+  m_last_part= part_id;
+  DBUG_RETURN(file->ha_rnd_pos(buf, (pos + PARTITION_BYTES_IN_POS)));
+}
+
+
+/*
+  Read row using position using given record to find
+
+  SYNOPSIS
+    rnd_pos_by_record()
+    record             Current record in MySQL Row Format
+
+  RETURN VALUE
+    >0                 Error code
+    0                  Success
+
+  DESCRIPTION
+    this works as position()+rnd_pos() functions, but does some extra work,
+    calculating m_last_part - the partition to where the 'record'
+    should go.
+
+    called from replication (log_event.cc)
+*/
+
+int ha_partition::rnd_pos_by_record(uchar *record)
+{
+  DBUG_ENTER("ha_partition::rnd_pos_by_record");
+
+  if (unlikely(get_part_for_buf(record, m_rec0, m_part_info, &m_last_part)))
+    DBUG_RETURN(1);
+
+  int err= m_file[m_last_part]->rnd_pos_by_record(record);
+  DBUG_RETURN(err);
+}
+
+
+/****************************************************************************
+                MODULE index scan
+****************************************************************************/
+/*
+  Positions an index cursor to the index specified in the handle. Fetches the
+  row if available. If the key value is null, begin at the first key of the
+  index.
+
+  There are loads of optimisations possible here for the partition handler.
+  The same optimisations can also be checked for full table scan although
+  only through conditions and not from index ranges.
+  Phase one optimisations:
+    Check if the fields of the partition function are bound. If so only use
+    the single partition it becomes bound to.
+  Phase two optimisations:
+    If it can be deducted through range or list partitioning that only a
+    subset of the partitions are used, then only use those partitions.
+*/
+
+
+/**
+  Setup the ordered record buffer and the priority queue.
+*/
+
+bool ha_partition::init_record_priority_queue()
+{
+  DBUG_ENTER("ha_partition::init_record_priority_queue");
+  DBUG_ASSERT(!m_ordered_rec_buffer);
+  /*
+    Initialize the ordered record buffer.
+  */
+  if (!m_ordered_rec_buffer)
+  {
+    size_t alloc_len;
+    uint used_parts= bitmap_bits_set(&m_part_info->read_partitions);
+
+    if (used_parts == 0) /* Do nothing since no records expected. */
+      DBUG_RETURN(false);
+
+    /* Allocate record buffer for each used partition. */
+    m_priority_queue_rec_len= m_rec_length + PARTITION_BYTES_IN_POS;
+    if (!m_using_extended_keys)
+       m_priority_queue_rec_len += get_open_file_sample()->ref_length;
+    alloc_len= used_parts * m_priority_queue_rec_len;
+    /* Allocate a key for temporary use when setting up the scan. */
+    alloc_len+= table_share->max_key_length;
+
+    if (!(m_ordered_rec_buffer= (uchar*)my_malloc(key_memory_partition_sort_buffer,
+                                                  alloc_len, MYF(MY_WME))))
+      DBUG_RETURN(true);
+
+    /*
+      We set-up one record per partition and each record has 2 bytes in
+      front where the partition id is written. This is used by ordered
+      index_read.
+      We also set-up a reference to the first record for temporary use in
+      setting up the scan.
+    */
+    char *ptr= (char*) m_ordered_rec_buffer;
+    uint i;
+    for (i= bitmap_get_first_set(&m_part_info->read_partitions);
+         i < m_tot_parts;
+         i= bitmap_get_next_set(&m_part_info->read_partitions, i))
+    {
+      DBUG_PRINT("info", ("init rec-buf for part %u", i));
+      int2store(ptr, i);
+      ptr+= m_priority_queue_rec_len;
+    }
+    m_start_key.key= (const uchar*)ptr;
+
+    /* Initialize priority queue, initialized to reading forward. */
+    int (*cmp_func)(void *, uchar *, uchar *);
+    void *cmp_arg= (void*) this;
+    if (!m_using_extended_keys && !(table_flags() & HA_SLOW_CMP_REF))
+      cmp_func= cmp_key_rowid_part_id;
+    else
+      cmp_func= cmp_key_part_id;
+    DBUG_PRINT("info", ("partition queue_init(1) used_parts: %u", used_parts));
+    if (init_queue(&m_queue, used_parts, 0, 0, cmp_func, cmp_arg, 0, 0))
+    {
+      my_free(m_ordered_rec_buffer);
+      m_ordered_rec_buffer= NULL;
+      DBUG_RETURN(true);
+    }
+  }
+  DBUG_RETURN(false);
+}
+
+
+/**
+  Destroy the ordered record buffer and the priority queue.
+*/
+
+void ha_partition::destroy_record_priority_queue()
+{
+  DBUG_ENTER("ha_partition::destroy_record_priority_queue");
+  if (m_ordered_rec_buffer)
+  {
+    delete_queue(&m_queue);
+    my_free(m_ordered_rec_buffer);
+    m_ordered_rec_buffer= NULL;
+  }
+  DBUG_VOID_RETURN;
+}
+
+
+/*
+  Initialize handler before start of index scan
+
+  SYNOPSIS
+    index_init()
+    inx                Index number
+    sorted             Is rows to be returned in sorted order
+
+  RETURN VALUE
+    >0                 Error code
+    0                  Success
+
+  DESCRIPTION
+    index_init is always called before starting index scans (except when
+    starting through index_read_idx and using read_range variants).
+*/
+
+int ha_partition::index_init(uint inx, bool sorted)
+{
+  int error= 0;
+  uint i;
+  DBUG_ENTER("ha_partition::index_init");
+  DBUG_PRINT("enter", ("partition this: %p  inx: %u  sorted: %u", this, inx, sorted));
+
+  active_index= inx;
+  m_part_spec.start_part= NO_CURRENT_PART_ID;
+  m_start_key.length= 0;
+  m_ordered= sorted;
+  m_ordered_scan_ongoing= FALSE;
+  m_curr_key_info[0]= table->key_info+inx;
+  if (pk_is_clustering_key(table->s->primary_key))
+  {
+    /*
+      if PK is clustered, then the key cmp must use the pk to
+      differentiate between equal key in given index.
+    */
+    DBUG_PRINT("info", ("Clustered pk, using pk as secondary cmp"));
+    m_curr_key_info[1]= table->key_info+table->s->primary_key;
+    m_curr_key_info[2]= NULL;
+    m_using_extended_keys= TRUE;
+  }
+  else
+  {
+    m_curr_key_info[1]= NULL;
+    m_using_extended_keys= FALSE;
+  }
+
+  if (init_record_priority_queue())
+    DBUG_RETURN(HA_ERR_OUT_OF_MEM);
+
+  /*
+    Some handlers only read fields as specified by the bitmap for the
+    read set. For partitioned handlers we always require that the
+    fields of the partition functions are read such that we can
+    calculate the partition id to place updated and deleted records.
+    But this is required for operations that may need to change data only.
+  */
+  if (get_lock_type() == F_WRLCK)
+  {
+    DBUG_PRINT("info", ("partition set part_field bitmap"));
+    bitmap_union(table->read_set, &m_part_info->full_part_field_set);
+  }
+  if (sorted)
+  {
+    /*
+      An ordered scan is requested. We must make sure all fields of the
+      used index are in the read set, as partitioning requires them for
+      sorting (see ha_partition::handle_ordered_index_scan).
+
+      The SQL layer may request an ordered index scan without having index
+      fields in the read set when
+       - it needs to do an ordered scan over an index prefix.
+       - it evaluates ORDER BY with SELECT COUNT(*) FROM t1.
+
+      TODO: handle COUNT(*) queries via unordered scan.
+    */
+    KEY **key_info= m_curr_key_info;
+    do
+    {
+      for (i= 0; i < (*key_info)->user_defined_key_parts; i++)
+        (*key_info)->key_part[i].field->register_field_in_read_map();
+    } while (*(++key_info));
+  }
+  for (i= bitmap_get_first_set(&m_part_info->read_partitions);
+       i < m_tot_parts;
+       i= bitmap_get_next_set(&m_part_info->read_partitions, i))
+  {
+    if (unlikely((error= m_file[i]->ha_index_init(inx, sorted))))
+      goto err;
+
+    DBUG_EXECUTE_IF("ha_partition_fail_index_init", {
+      i++;
+      error= HA_ERR_NO_PARTITION_FOUND;
+      goto err;
+    });
+  }
+err:
+  if (unlikely(error))
+  {
+    /* End the previously initialized indexes. */
+    uint j;
+    for (j= bitmap_get_first_set(&m_part_info->read_partitions);
+         j < i;
+         j= bitmap_get_next_set(&m_part_info->read_partitions, j))
+    {
+      (void) m_file[j]->ha_index_end();
+    }
+    destroy_record_priority_queue();
+  }
+  DBUG_RETURN(error);
+}
+
+
+/*
+  End of index scan
+
+  SYNOPSIS
+    index_end()
+
+  RETURN VALUE
+    >0                 Error code
+    0                  Success
+
+  DESCRIPTION
+    index_end is called at the end of an index scan to clean up any
+    things needed to clean up.
+*/
+
+int ha_partition::index_end()
+{
+  int error= 0;
+  handler **file;
+  DBUG_ENTER("ha_partition::index_end");
+
+  active_index= MAX_KEY;
+  m_part_spec.start_part= NO_CURRENT_PART_ID;
+  file= m_file;
+  do
+  {
+    if ((*file)->inited == INDEX)
+    {
+      int tmp;
+      if ((tmp= (*file)->ha_index_end()))
+        error= tmp;
+    }
+    else if ((*file)->inited == RND)
+    {
+      // Possible due to MRR
+      int tmp;
+      if ((tmp= (*file)->ha_rnd_end()))
+        error= tmp;
+    }
+  } while (*(++file));
+  destroy_record_priority_queue();
+  DBUG_RETURN(error);
+}
+
+
+/*
+  Read one record in an index scan and start an index scan
+
+  SYNOPSIS
+    index_read_map()
+    buf                    Read row in MySQL Row Format
+    key                    Key parts in consecutive order
+    keypart_map            Which part of key is used
+    find_flag              What type of key condition is used
+
+  RETURN VALUE
+    >0                 Error code
+    0                  Success
+
+  DESCRIPTION
+    index_read_map starts a new index scan using a start key. The MySQL Server
+    will check the end key on its own. Thus to function properly the
+    partitioned handler need to ensure that it delivers records in the sort
+    order of the MySQL Server.
+    index_read_map can be restarted without calling index_end on the previous
+    index scan and without calling index_init. In this case the index_read_map
+    is on the same index as the previous index_scan. This is particularly
+    used in conjuntion with multi read ranges.
+*/
+
+int ha_partition::index_read_map(uchar *buf, const uchar *key,
+                                 key_part_map keypart_map,
+                                 enum ha_rkey_function find_flag)
+{
+  DBUG_ENTER("ha_partition::index_read_map");
+  decrement_statistics(&SSV::ha_read_key_count);
+  end_range= 0;
+  m_index_scan_type= partition_index_read;
+  m_start_key.key= key;
+  m_start_key.keypart_map= keypart_map;
+  m_start_key.flag= find_flag;
+  DBUG_RETURN(common_index_read(buf, TRUE));
+}
+
+
+/* Compare two part_no partition numbers */
+static int cmp_part_ids(uchar *ref1, uchar *ref2)
+{
+  uint32 diff2= uint2korr(ref2);
+  uint32 diff1= uint2korr(ref1);
+  if (diff2 > diff1)
+    return -1;
+  if (diff2 < diff1)
+    return 1;
+  return 0;
+}
+
+
+/*
+  @brief
+    Provide ordering by (key_value, part_no).
+*/
+
+extern "C" int cmp_key_part_id(void *ptr, uchar *ref1, uchar *ref2)
+{
+  ha_partition *file= (ha_partition*)ptr;
+  int res;
+  if ((res= key_rec_cmp(file->m_curr_key_info, ref1 + PARTITION_BYTES_IN_POS,
+                        ref2 + PARTITION_BYTES_IN_POS)))
+  {
+    return res;
+  }
+  return cmp_part_ids(ref1, ref2);
+}
+
+/*
+  @brief
+    Provide ordering by (key_value, underying_table_rowid, part_no).
+*/
+extern "C" int cmp_key_rowid_part_id(void *ptr, uchar *ref1, uchar *ref2)
+{
+  ha_partition *file= (ha_partition*)ptr;
+  int res;
+
+  if ((res= key_rec_cmp(file->m_curr_key_info, ref1 + PARTITION_BYTES_IN_POS,
+                        ref2 + PARTITION_BYTES_IN_POS)))
+  {
+    return res;
+  }
+  if ((res= file->get_open_file_sample()->cmp_ref(ref1 +
+          PARTITION_BYTES_IN_POS + file->m_rec_length,
+          ref2 + PARTITION_BYTES_IN_POS + file->m_rec_length)))
+  {
+    return res;
+  }
+  return cmp_part_ids(ref1, ref2);
+}
+
+
+/**
+  Common routine for a number of index_read variants
+
+  @param buf             Buffer where the record should be returned.
+  @param have_start_key  TRUE <=> the left endpoint is available, i.e.
+                         we're in index_read call or in read_range_first
+                         call and the range has left endpoint.
+                         FALSE <=> there is no left endpoint (we're in
+                         read_range_first() call and the range has no left
+                         endpoint).
+
+  @return Operation status
+    @retval 0      OK
+    @retval HA_ERR_END_OF_FILE   Whole index scanned, without finding the record.
+    @retval HA_ERR_KEY_NOT_FOUND Record not found, but index cursor positioned.
+    @retval other  error code.
+
+  @details
+    Start scanning the range (when invoked from read_range_first()) or doing
+    an index lookup (when invoked from index_read_XXX):
+     - If possible, perform partition selection
+     - Find the set of partitions we're going to use
+     - Depending on whether we need ordering:
+        NO:  Get the first record from first used partition (see
+             handle_unordered_scan_next_partition)
+        YES: Fill the priority queue and get the record that is the first in
+             the ordering
+*/
+
+int ha_partition::common_index_read(uchar *buf, bool have_start_key)
+{
+  int error;
+  uint UNINIT_VAR(key_len); /* used if have_start_key==TRUE */
+  bool reverse_order= FALSE;
+  DBUG_ENTER("ha_partition::common_index_read");
+
+  DBUG_PRINT("info", ("m_ordered %u m_ordered_scan_ong %u",
+                      m_ordered, m_ordered_scan_ongoing));
+
+  if (have_start_key)
+  {
+    m_start_key.length= key_len= calculate_key_len(table, active_index,
+                                                   m_start_key.key,
+                                                   m_start_key.keypart_map);
+    DBUG_PRINT("info", ("have_start_key map %lu find_flag %u len %u",
+                        m_start_key.keypart_map, m_start_key.flag, key_len));
+    DBUG_ASSERT(key_len);
+  }
+  if (unlikely((error= partition_scan_set_up(buf, have_start_key))))
+  {
+    DBUG_RETURN(error);
+  }
+
+  if (have_start_key &&
+      (m_start_key.flag == HA_READ_PREFIX_LAST ||
+       m_start_key.flag == HA_READ_PREFIX_LAST_OR_PREV ||
+       m_start_key.flag == HA_READ_BEFORE_KEY))
+  {
+    reverse_order= TRUE;
+    m_ordered_scan_ongoing= TRUE;
+  }
+  DBUG_PRINT("info", ("m_ordered %u m_o_scan_ong %u have_start_key %u",
+                      m_ordered, m_ordered_scan_ongoing, have_start_key));
+  if (!m_ordered_scan_ongoing)
+   {
+    /*
+      We use unordered index scan when read_range is used and flag
+      is set to not use ordered.
+      We also use an unordered index scan when the number of partitions to
+      scan is only one.
+      The unordered index scan will use the partition set created.
+    */
+    DBUG_PRINT("info", ("doing unordered scan"));
+    error= handle_pre_scan(FALSE, FALSE);
+    if (likely(!error))
+      error= handle_unordered_scan_next_partition(buf);
+  }
+  else
+  {
+    /*
+      In all other cases we will use the ordered index scan. This will use
+      the partition set created by the get_partition_set method.
+    */
+    error= handle_ordered_index_scan(buf, reverse_order);
+  }
+  DBUG_RETURN(error);
+}
+
+
+/*
+  Start an index scan from leftmost record and return first record
+
+  SYNOPSIS
+    index_first()
+    buf                 Read row in MySQL Row Format
+
+  RETURN VALUE
+    >0                  Error code
+    0                   Success
+
+  DESCRIPTION
+    index_first() asks for the first key in the index.
+    This is similar to index_read except that there is no start key since
+    the scan starts from the leftmost entry and proceeds forward with
+    index_next.
+
+    Called from opt_range.cc, opt_sum.cc, sql_handler.cc,
+    and sql_select.cc.
+*/
+
+int ha_partition::index_first(uchar * buf)
+{
+  DBUG_ENTER("ha_partition::index_first");
+  decrement_statistics(&SSV::ha_read_first_count);
+
+  end_range= 0;
+  m_index_scan_type= partition_index_first;
+  DBUG_RETURN(common_first_last(buf));
+}
+
+
+/*
+  Start an index scan from rightmost record and return first record
+
+  SYNOPSIS
+    index_last()
+    buf                 Read row in MySQL Row Format
+
+  RETURN VALUE
+    >0                  Error code
+    0                   Success
+
+  DESCRIPTION
+    index_last() asks for the last key in the index.
+    This is similar to index_read except that there is no start key since
+    the scan starts from the rightmost entry and proceeds forward with
+    index_prev.
+
+    Called from opt_range.cc, opt_sum.cc, sql_handler.cc,
+    and sql_select.cc.
+*/
+
+int ha_partition::index_last(uchar * buf)
+{
+  DBUG_ENTER("ha_partition::index_last");
+  decrement_statistics(&SSV::ha_read_last_count);
+
+  m_index_scan_type= partition_index_last;
+  DBUG_RETURN(common_first_last(buf));
+}
+
+/*
+  Common routine for index_first/index_last
+
+  SYNOPSIS
+    ha_partition::common_first_last()
+
+  see index_first for rest
+*/
+
+int ha_partition::common_first_last(uchar *buf)
+{
+  int error;
+
+  if (unlikely((error= partition_scan_set_up(buf, FALSE))))
+    return error;
+  if (!m_ordered_scan_ongoing &&
+      m_index_scan_type != partition_index_last)
+  {
+    if (unlikely((error= handle_pre_scan(FALSE, check_parallel_search()))))
+      return error;
+   return handle_unordered_scan_next_partition(buf);
+  }
+  return handle_ordered_index_scan(buf, FALSE);
+}
+
+
+/*
+  Optimization of the default implementation to take advantage of dynamic
+  partition pruning.
+*/
+int ha_partition::index_read_idx_map(uchar *buf, uint index,
+                                     const uchar *key,
+                                     key_part_map keypart_map,
+                                     enum ha_rkey_function find_flag)
+{
+  int error= HA_ERR_KEY_NOT_FOUND;
+  DBUG_ENTER("ha_partition::index_read_idx_map");
+  decrement_statistics(&SSV::ha_read_key_count);
+
+  if (find_flag == HA_READ_KEY_EXACT)
+  {
+    uint part;
+    m_start_key.key= key;
+    m_start_key.keypart_map= keypart_map;
+    m_start_key.flag= find_flag;
+    m_start_key.length= calculate_key_len(table, index, m_start_key.key,
+                                          m_start_key.keypart_map);
+
+    get_partition_set(table, buf, index, &m_start_key, &m_part_spec);
+
+    /* The start part is must be marked as used. */
+    DBUG_ASSERT(m_part_spec.start_part > m_part_spec.end_part ||
+                bitmap_is_set(&(m_part_info->read_partitions),
+                              m_part_spec.start_part));
+
+    for (part= m_part_spec.start_part;
+         part <= m_part_spec.end_part;
+         part= bitmap_get_next_set(&m_part_info->read_partitions, part))
+    {
+      error= m_file[part]->ha_index_read_idx_map(buf, index, key,
+                                                 keypart_map, find_flag);
+      if (likely(error != HA_ERR_KEY_NOT_FOUND &&
+                 error != HA_ERR_END_OF_FILE))
+        break;
+    }
+    if (part <= m_part_spec.end_part)
+      m_last_part= part;
+  }
+  else
+  {
+    /*
+      If not only used with READ_EXACT, we should investigate if possible
+      to optimize for other find_flag's as well.
+    */
+    DBUG_ASSERT(0);
+    /* fall back on the default implementation */
+    error= handler::index_read_idx_map(buf, index, key, keypart_map, find_flag);
+  }
+  DBUG_RETURN(error);
+}
+
+
+/*
+  Read next record in a forward index scan
+
+  SYNOPSIS
+    index_next()
+    buf                   Read row in MySQL Row Format
+
+  RETURN VALUE
+    >0                    Error code
+    0                     Success
+
+  DESCRIPTION
+    Used to read forward through the index.
+*/
+
+int ha_partition::index_next(uchar * buf)
+{
+  DBUG_ENTER("ha_partition::index_next");
+  decrement_statistics(&SSV::ha_read_next_count);
+
+  /*
+    TODO(low priority):
+    If we want partition to work with the HANDLER commands, we
+    must be able to do index_last() -> index_prev() -> index_next()
+    and if direction changes, we must step back those partitions in
+    the record queue so we don't return a value from the wrong direction.
+  */
+  if (m_index_scan_type == partition_index_last)
+    DBUG_RETURN(HA_ERR_WRONG_COMMAND);
+  if (!m_ordered_scan_ongoing)
+  {
+    DBUG_RETURN(handle_unordered_next(buf, FALSE));
+  }
+  DBUG_RETURN(handle_ordered_next(buf, FALSE));
+}
+
+
+/*
+  Read next record special
+
+  SYNOPSIS
+    index_next_same()
+    buf                   Read row in MySQL Row Format
+    key                   Key
+    keylen                Length of key
+
+  RETURN VALUE
+    >0                    Error code
+    0                     Success
+
+  DESCRIPTION
+    This routine is used to read the next but only if the key is the same
+    as supplied in the call.
+*/
+
+int ha_partition::index_next_same(uchar *buf, const uchar *key, uint keylen)
+{
+  DBUG_ENTER("ha_partition::index_next_same");
+  decrement_statistics(&SSV::ha_read_next_count);
+
+  DBUG_ASSERT(keylen == m_start_key.length);
+  if (m_index_scan_type == partition_index_last)
+    DBUG_RETURN(HA_ERR_WRONG_COMMAND);
+  if (!m_ordered_scan_ongoing)
+    DBUG_RETURN(handle_unordered_next(buf, TRUE));
+  DBUG_RETURN(handle_ordered_next(buf, TRUE));
+}
+
+
+int ha_partition::index_read_last_map(uchar *buf,
+                                          const uchar *key,
+                                          key_part_map keypart_map)
+{
+  DBUG_ENTER("ha_partition::index_read_last_map");
+
+  m_ordered= true;                              // Safety measure
+  end_range= NULL;
+  m_index_scan_type= partition_index_read_last;
+  m_start_key.key= key;
+  m_start_key.keypart_map= keypart_map;
+  m_start_key.flag= HA_READ_PREFIX_LAST;
+  DBUG_RETURN(common_index_read(buf, true));
+}
+
+
+/*
+  Read next record when performing index scan backwards
+
+  SYNOPSIS
+    index_prev()
+    buf                   Read row in MySQL Row Format
+
+  RETURN VALUE
+    >0                    Error code
+    0                     Success
+
+  DESCRIPTION
+    Used to read backwards through the index.
+*/
+
+int ha_partition::index_prev(uchar * buf)
+{
+  DBUG_ENTER("ha_partition::index_prev");
+  decrement_statistics(&SSV::ha_read_prev_count);
+
+  /* TODO: read comment in index_next */
+  if (m_index_scan_type == partition_index_first)
+    DBUG_RETURN(HA_ERR_WRONG_COMMAND);
+  DBUG_RETURN(handle_ordered_prev(buf));
+}
+
+
+/*
+  Start a read of one range with start and end key
+
+  SYNOPSIS
+    read_range_first()
+    start_key           Specification of start key
+    end_key             Specification of end key
+    eq_range_arg        Is it equal range
+    sorted              Should records be returned in sorted order
+
+  RETURN VALUE
+    >0                    Error code
+    0                     Success
+
+  DESCRIPTION
+    We reimplement read_range_first since we don't want the compare_key
+    check at the end. This is already performed in the partition handler.
+    read_range_next is very much different due to that we need to scan
+    all underlying handlers.
+*/
+
+int ha_partition::read_range_first(const key_range *start_key,
+				   const key_range *end_key,
+				   bool eq_range_arg, bool sorted)
+{
+  int error;
+  DBUG_ENTER("ha_partition::read_range_first");
+
+  m_ordered= sorted;
+  eq_range= eq_range_arg;
+  set_end_range(end_key);
+
+  range_key_part= m_curr_key_info[0]->key_part;
+  if (start_key)
+    m_start_key= *start_key;
+  else
+    m_start_key.key= NULL;
+
+  m_index_scan_type= partition_read_range;
+  error= common_index_read(m_rec0, MY_TEST(start_key));
+  DBUG_RETURN(error);
+}
+
+
+/*
+  Read next record in read of a range with start and end key
+
+  SYNOPSIS
+    read_range_next()
+
+  RETURN VALUE
+    >0                    Error code
+    0                     Success
+*/
+
+int ha_partition::read_range_next()
+{
+  DBUG_ENTER("ha_partition::read_range_next");
+
+  if (m_ordered_scan_ongoing)
+  {
+    DBUG_RETURN(handle_ordered_next(table->record[0], eq_range));
+  }
+  DBUG_RETURN(handle_unordered_next(table->record[0], eq_range));
+}
+
+/**
+   Create a copy of all keys used by multi_range_read()
+
+   @retval 0 ok
+   @retval HA_ERR_END_OF_FILE no keys in range
+   @retval other value: error
+
+   TODO to save memory:
+   - If (mrr_mode & HA_MRR_MATERIALIZED_KEYS) is set then the keys data is
+     stable and we don't have to copy the keys, only store a pointer to the
+     key.
+   - When allocating key data, store things in a MEM_ROOT buffer instead of
+     a malloc() per key. This will simplify and speed up the current code
+     and use less memory.
+*/
+
+int ha_partition::multi_range_key_create_key(RANGE_SEQ_IF *seq,
+                                             range_seq_t seq_it)
+{
+  uint i, length;
+  key_range *start_key, *end_key;
+  KEY_MULTI_RANGE *range;
+  DBUG_ENTER("ha_partition::multi_range_key_create_key");
+
+  bitmap_clear_all(&m_mrr_used_partitions);
+  m_mrr_range_length= 0;
+  bzero(m_part_mrr_range_length,
+        sizeof(*m_part_mrr_range_length) * m_tot_parts);
+  if (!m_mrr_range_first)
+  {
+    if (!(m_mrr_range_first= (PARTITION_KEY_MULTI_RANGE *)
+          my_multi_malloc(PSI_INSTRUMENT_ME, MYF(MY_WME),
+                          &m_mrr_range_current, sizeof(PARTITION_KEY_MULTI_RANGE),
+                          NullS)))
+      DBUG_RETURN(HA_ERR_OUT_OF_MEM);
+
+    m_mrr_range_first->id= 1;
+    m_mrr_range_first->key[0]= NULL;
+    m_mrr_range_first->key[1]= NULL;
+    m_mrr_range_first->next= NULL;
+  }
+  else
+    m_mrr_range_current= m_mrr_range_first;
+
+  for (i= 0; i < m_tot_parts; i++)
+  {
+    if (!m_part_mrr_range_first[i])
+    {
+      if (!(m_part_mrr_range_first[i]= (PARTITION_PART_KEY_MULTI_RANGE *)
+            my_multi_malloc(PSI_INSTRUMENT_ME, MYF(MY_WME | MY_ZEROFILL),
+                            &m_part_mrr_range_current[i], sizeof(PARTITION_PART_KEY_MULTI_RANGE),
+                            NullS)))
+        DBUG_RETURN(HA_ERR_OUT_OF_MEM);
+    }
+    else
+    {
+      m_part_mrr_range_current[i]= m_part_mrr_range_first[i];
+      m_part_mrr_range_current[i]->partition_key_multi_range= NULL;
+    }
+  }
+  m_mrr_range_current->key_multi_range.start_key.key= NULL;
+  m_mrr_range_current->key_multi_range.end_key.key= NULL;
+
+  while (!seq->next(seq_it, &m_mrr_range_current->key_multi_range))
+  {
+    m_mrr_range_length++;
+    range= &m_mrr_range_current->key_multi_range;
+
+    /* Copy start key */
+    start_key= &range->start_key;
+    DBUG_PRINT("info",("partition range->range_flag: %u", range->range_flag));
+    DBUG_PRINT("info",("partition start_key->key: %p", start_key->key));
+    DBUG_PRINT("info",("partition start_key->length: %u", start_key->length));
+    DBUG_PRINT("info",("partition start_key->keypart_map: %lu",
+                       start_key->keypart_map));
+    DBUG_PRINT("info",("partition start_key->flag: %u", start_key->flag));
+
+    if (start_key->key)
+    {
+      length= start_key->length;
+      if (!m_mrr_range_current->key[0] ||
+          m_mrr_range_current->length[0] < length)
+      {
+        if (m_mrr_range_current->key[0])
+          my_free(m_mrr_range_current->key[0]);
+        if (!(m_mrr_range_current->key[0]=
+              (uchar *) my_malloc(PSI_INSTRUMENT_ME, length, MYF(MY_WME))))
+          DBUG_RETURN(HA_ERR_OUT_OF_MEM);
+        m_mrr_range_current->length[0]= length;
+      }
+      memcpy(m_mrr_range_current->key[0], start_key->key, length);
+      start_key->key= m_mrr_range_current->key[0];
+    }
+
+    /* Copy end key */
+    end_key= &range->end_key;
+    DBUG_PRINT("info",("partition end_key->key: %p", end_key->key));
+    DBUG_PRINT("info",("partition end_key->length: %u", end_key->length));
+    DBUG_PRINT("info",("partition end_key->keypart_map: %lu",
+                       end_key->keypart_map));
+    DBUG_PRINT("info",("partition end_key->flag: %u", end_key->flag));
+    if (end_key->key)
+    {
+      length= end_key->length;
+      if (!m_mrr_range_current->key[1] ||
+          m_mrr_range_current->length[1] < length)
+      {
+        if (m_mrr_range_current->key[1])
+          my_free(m_mrr_range_current->key[1]);
+        if (!(m_mrr_range_current->key[1]=
+              (uchar *) my_malloc(PSI_INSTRUMENT_ME, length, MYF(MY_WME))))
+          DBUG_RETURN(HA_ERR_OUT_OF_MEM);
+        m_mrr_range_current->length[1]= length;
+      }
+      memcpy(m_mrr_range_current->key[1], end_key->key, length);
+      end_key->key= m_mrr_range_current->key[1];
+    }
+
+    m_mrr_range_current->ptr= m_mrr_range_current->key_multi_range.ptr;
+    m_mrr_range_current->key_multi_range.ptr= m_mrr_range_current;
+
+    if (start_key->key && (start_key->flag & HA_READ_KEY_EXACT))
+      get_partition_set(table, table->record[0], active_index,
+                        start_key, &m_part_spec);
+    else
+    {
+      m_part_spec.start_part= 0;
+      m_part_spec.end_part= m_tot_parts - 1;
+    }
+
+    /* Copy key to those partitions that needs it */
+    for (i= m_part_spec.start_part; i <= m_part_spec.end_part; i++)
+    {
+      if (bitmap_is_set(&(m_part_info->read_partitions), i))
+      {
+        bitmap_set_bit(&m_mrr_used_partitions, i);
+        m_part_mrr_range_length[i]++;
+        m_part_mrr_range_current[i]->partition_key_multi_range=
+          m_mrr_range_current;
+
+        if (!m_part_mrr_range_current[i]->next)
+        {
+          PARTITION_PART_KEY_MULTI_RANGE *tmp_part_mrr_range;
+          if (!(tmp_part_mrr_range= (PARTITION_PART_KEY_MULTI_RANGE *)
+                my_malloc(PSI_INSTRUMENT_ME, sizeof(PARTITION_PART_KEY_MULTI_RANGE),
+                          MYF(MY_WME | MY_ZEROFILL))))
+            DBUG_RETURN(HA_ERR_OUT_OF_MEM);
+
+          m_part_mrr_range_current[i]->next= tmp_part_mrr_range;
+          m_part_mrr_range_current[i]= tmp_part_mrr_range;
+        }
+        else
+        {
+          m_part_mrr_range_current[i]= m_part_mrr_range_current[i]->next;
+          m_part_mrr_range_current[i]->partition_key_multi_range= NULL;
+        }
+      }
+    }
+
+    if (!m_mrr_range_current->next)
+    {
+      /* Add end of range sentinel */
+      PARTITION_KEY_MULTI_RANGE *tmp_mrr_range;
+      if (!(tmp_mrr_range= (PARTITION_KEY_MULTI_RANGE *)
+            my_malloc(PSI_INSTRUMENT_ME, sizeof(PARTITION_KEY_MULTI_RANGE), MYF(MY_WME))))
+        DBUG_RETURN(HA_ERR_OUT_OF_MEM);
+
+      tmp_mrr_range->id= m_mrr_range_current->id + 1;
+      tmp_mrr_range->key[0]= NULL;
+      tmp_mrr_range->key[1]= NULL;
+      tmp_mrr_range->next= NULL;
+      m_mrr_range_current->next= tmp_mrr_range;
+    }
+    m_mrr_range_current= m_mrr_range_current->next;
+  }
+
+  if (!m_mrr_range_length)
+  {
+    DBUG_PRINT("Warning",("No keys to use for mrr"));
+    DBUG_RETURN(HA_ERR_END_OF_FILE);
+  }
+
+  /* set start and end part */
+  m_part_spec.start_part= bitmap_get_first_set(&m_mrr_used_partitions);
+
+  for (i= m_tot_parts; i-- > 0;)
+  {
+    if (bitmap_is_set(&m_mrr_used_partitions, i))
+    {
+      m_part_spec.end_part= i;
+      break;
+    }
+  }
+  for (i= 0; i < m_tot_parts; i++)
+  {
+    m_partition_part_key_multi_range_hld[i].partition= this;
+    m_partition_part_key_multi_range_hld[i].part_id= i;
+    m_partition_part_key_multi_range_hld[i].partition_part_key_multi_range=
+      m_part_mrr_range_first[i];
+  }
+  DBUG_PRINT("return",("OK"));
+  DBUG_RETURN(0);
+}
+
+
+static void partition_multi_range_key_get_key_info(void *init_params,
+                                                   uint *length,
+                                                   key_part_map *map)
+{
+  PARTITION_PART_KEY_MULTI_RANGE_HLD *hld=
+    (PARTITION_PART_KEY_MULTI_RANGE_HLD *)init_params;
+  ha_partition *partition= hld->partition;
+  key_range *start_key= (&partition->m_mrr_range_first->
+                         key_multi_range.start_key);
+  DBUG_ENTER("partition_multi_range_key_get_key_info");
+  *length= start_key->length;
+  *map= start_key->keypart_map;
+  DBUG_VOID_RETURN;
+}
+
+
+static range_seq_t partition_multi_range_key_init(void *init_params,
+                                                  uint n_ranges,
+                                                  uint flags)
+{
+  PARTITION_PART_KEY_MULTI_RANGE_HLD *hld=
+    (PARTITION_PART_KEY_MULTI_RANGE_HLD *)init_params;
+  ha_partition *partition= hld->partition;
+  uint i= hld->part_id;
+  DBUG_ENTER("partition_multi_range_key_init");
+  // not used: partition->m_mrr_range_init_flags= flags;
+  hld->partition_part_key_multi_range= partition->m_part_mrr_range_first[i];
+  DBUG_RETURN(init_params);
+}
+
+
+static bool partition_multi_range_key_next(range_seq_t seq,
+                                           KEY_MULTI_RANGE *range)
+{
+  PARTITION_PART_KEY_MULTI_RANGE_HLD *hld=
+    (PARTITION_PART_KEY_MULTI_RANGE_HLD *)seq;
+  PARTITION_KEY_MULTI_RANGE *partition_key_multi_range=
+    hld->partition_part_key_multi_range->partition_key_multi_range;
+  DBUG_ENTER("partition_multi_range_key_next");
+  if (!partition_key_multi_range)
+    DBUG_RETURN(TRUE);
+  *range= partition_key_multi_range->key_multi_range;
+  hld->partition_part_key_multi_range=
+    hld->partition_part_key_multi_range->next;
+  DBUG_RETURN(FALSE);
+}
+
+
+static bool partition_multi_range_key_skip_record(range_seq_t seq,
+                                                  range_id_t range_info,
+                                                  uchar *rowid)
+{
+  PARTITION_PART_KEY_MULTI_RANGE_HLD *hld=
+    (PARTITION_PART_KEY_MULTI_RANGE_HLD *)seq;
+  PARTITION_KEY_MULTI_RANGE *pkmr= (PARTITION_KEY_MULTI_RANGE *)range_info;
+  DBUG_ENTER("partition_multi_range_key_skip_record");
+  DBUG_RETURN(hld->partition->m_seq_if->skip_record(hld->partition->m_seq,
+                                                    pkmr->ptr, rowid));
+}
+
+
+static bool partition_multi_range_key_skip_index_tuple(range_seq_t seq,
+                                                       range_id_t range_info)
+{
+  PARTITION_PART_KEY_MULTI_RANGE_HLD *hld=
+    (PARTITION_PART_KEY_MULTI_RANGE_HLD *)seq;
+  PARTITION_KEY_MULTI_RANGE *pkmr= (PARTITION_KEY_MULTI_RANGE *)range_info;
+  DBUG_ENTER("partition_multi_range_key_skip_index_tuple");
+  DBUG_RETURN(hld->partition->m_seq_if->skip_index_tuple(hld->partition->m_seq,
+                                                         pkmr->ptr));
+}
+
+ha_rows ha_partition::multi_range_read_info_const(uint keyno,
+                                                  RANGE_SEQ_IF *seq,
+                                                  void *seq_init_param,
+                                                  uint n_ranges, uint *bufsz,
+                                                  uint *mrr_mode,
+                                                  Cost_estimate *cost)
+{
+  int error;
+  uint i;
+  handler **file;
+  ha_rows rows= 0;
+  uint ret_mrr_mode= 0;
+  range_seq_t seq_it;
+  part_id_range save_part_spec;
+  Cost_estimate part_cost;
+  DBUG_ENTER("ha_partition::multi_range_read_info_const");
+  DBUG_PRINT("enter", ("partition this: %p", this));
+
+  m_mrr_new_full_buffer_size= 0;
+  save_part_spec= m_part_spec;
+
+  cost->reset();
+
+  seq_it= seq->init(seq_init_param, n_ranges, *mrr_mode);
+  if (unlikely((error= multi_range_key_create_key(seq, seq_it))))
+  {
+    if (likely(error == HA_ERR_END_OF_FILE))    // No keys in range
+    {
+      rows= 0;
+      goto end;
+    }
+    /*
+      This error means that we can't do multi_range_read for the moment
+      (probably running out of memory) and we need to fallback to
+      normal reads
+    */
+    m_part_spec= save_part_spec;
+    DBUG_RETURN(HA_POS_ERROR);
+  }
+  m_part_seq_if.get_key_info=
+    seq->get_key_info ? partition_multi_range_key_get_key_info : NULL;
+  m_part_seq_if.init= partition_multi_range_key_init;
+  m_part_seq_if.next= partition_multi_range_key_next;
+  m_part_seq_if.skip_record= (seq->skip_record ?
+                              partition_multi_range_key_skip_record : NULL);
+  m_part_seq_if.skip_index_tuple= (seq->skip_index_tuple ?
+                                   partition_multi_range_key_skip_index_tuple :
+                                   NULL);
+  file= m_file;
+  do
+  {
+    i= (uint)(file - m_file);
+    DBUG_PRINT("info",("partition part_id: %u", i));
+    if (bitmap_is_set(&m_mrr_used_partitions, i))
+    {
+      ha_rows tmp_rows;
+      uint tmp_mrr_mode;
+      m_mrr_buffer_size[i]= 0;
+      part_cost.reset();
+      tmp_mrr_mode= *mrr_mode;
+      tmp_rows= (*file)->
+        multi_range_read_info_const(keyno, &m_part_seq_if,
+                                    &m_partition_part_key_multi_range_hld[i],
+                                    m_part_mrr_range_length[i],
+                                    &m_mrr_buffer_size[i],
+                                    &tmp_mrr_mode, &part_cost);
+      if (tmp_rows == HA_POS_ERROR)
+      {
+        m_part_spec= save_part_spec;
+        DBUG_RETURN(HA_POS_ERROR);
+      }
+      cost->add(&part_cost);
+      rows+= tmp_rows;
+      ret_mrr_mode|= tmp_mrr_mode;
+      m_mrr_new_full_buffer_size+= m_mrr_buffer_size[i];
+    }
+  } while (*(++file));
+  *mrr_mode= ret_mrr_mode;
+
+end:
+  m_part_spec= save_part_spec;
+  DBUG_RETURN(rows);
+}
+
+
+ha_rows ha_partition::multi_range_read_info(uint keyno, uint n_ranges,
+                                            uint keys,
+                                            uint key_parts, uint *bufsz,
+                                            uint *mrr_mode,
+                                            Cost_estimate *cost)
+{
+  uint i;
+  handler **file;
+  ha_rows rows= 0;
+  Cost_estimate part_cost;
+  DBUG_ENTER("ha_partition::multi_range_read_info");
+  DBUG_PRINT("enter", ("partition this: %p", this));
+
+  cost->reset();
+
+  m_mrr_new_full_buffer_size= 0;
+  file= m_file;
+  do
+  {
+    i= (uint)(file - m_file);
+    if (bitmap_is_set(&(m_part_info->read_partitions), (i)))
+    {
+      ha_rows tmp_rows;
+      m_mrr_buffer_size[i]= 0;
+      part_cost.reset();
+      if ((tmp_rows= (*file)->multi_range_read_info(keyno, n_ranges, keys,
+                                                    key_parts,
+                                                    &m_mrr_buffer_size[i],
+                                                    mrr_mode, &part_cost)))
+        DBUG_RETURN(rows);
+      cost->add(&part_cost);
+      rows+= tmp_rows;
+      m_mrr_new_full_buffer_size+= m_mrr_buffer_size[i];
+    }
+  } while (*(++file));
+
+  DBUG_RETURN(0);
+}
+
+
+int ha_partition::multi_range_read_init(RANGE_SEQ_IF *seq,
+                                        void *seq_init_param,
+                                        uint n_ranges, uint mrr_mode,
+                                        HANDLER_BUFFER *buf)
+{
+  int error;
+  uint i;
+  handler **file;
+  uchar *tmp_buffer;
+  DBUG_ENTER("ha_partition::multi_range_read_init");
+  DBUG_PRINT("enter", ("partition this: %p", this));
+
+  eq_range= 0;
+  m_seq_if= seq;
+  m_seq= seq->init(seq_init_param, n_ranges, mrr_mode);
+  if (unlikely((error= multi_range_key_create_key(seq, m_seq))))
+    DBUG_RETURN(0);
+
+  m_part_seq_if.get_key_info= (seq->get_key_info ?
+                               partition_multi_range_key_get_key_info :
+                               NULL);
+  m_part_seq_if.init= partition_multi_range_key_init;
+  m_part_seq_if.next= partition_multi_range_key_next;
+  m_part_seq_if.skip_record= (seq->skip_record ?
+                              partition_multi_range_key_skip_record :
+                              NULL);
+  m_part_seq_if.skip_index_tuple= (seq->skip_index_tuple ?
+                                   partition_multi_range_key_skip_index_tuple :
+                                   NULL);
+
+  /* m_mrr_new_full_buffer_size was calculated in multi_range_read_info */
+  if (m_mrr_full_buffer_size < m_mrr_new_full_buffer_size)
+  {
+    if (m_mrr_full_buffer)
+      my_free(m_mrr_full_buffer);
+    if (!(m_mrr_full_buffer=
+          (uchar *) my_malloc(PSI_INSTRUMENT_ME, m_mrr_new_full_buffer_size, MYF(MY_WME))))
+    {
+      m_mrr_full_buffer_size= 0;
+      error= HA_ERR_OUT_OF_MEM;
+      goto error;
+    }
+    m_mrr_full_buffer_size= m_mrr_new_full_buffer_size;
+  }
+
+  tmp_buffer= m_mrr_full_buffer;
+  file= m_file;
+  do
+  {
+    i= (uint)(file - m_file);
+    DBUG_PRINT("info",("partition part_id: %u", i));
+    if (bitmap_is_set(&m_mrr_used_partitions, i))
+    {
+      if (m_mrr_new_full_buffer_size)
+      {
+        if (m_mrr_buffer_size[i])
+        {
+          m_mrr_buffer[i].buffer= tmp_buffer;
+          m_mrr_buffer[i].end_of_used_area= tmp_buffer;
+          tmp_buffer+= m_mrr_buffer_size[i];
+          m_mrr_buffer[i].buffer_end= tmp_buffer;
+        }
+      }
+      else
+        m_mrr_buffer[i]= *buf;
+
+      if (unlikely((error= (*file)->
+                    multi_range_read_init(&m_part_seq_if,
+                                          &m_partition_part_key_multi_range_hld[i],
+                                          m_part_mrr_range_length[i],
+                                          mrr_mode,
+                                          &m_mrr_buffer[i]))))
+        goto error;
+      m_stock_range_seq[i]= 0;
+    }
+  } while (*(++file));
+
+  m_multi_range_read_first= TRUE;
+  m_mrr_range_current= m_mrr_range_first;
+  m_index_scan_type= partition_read_multi_range;
+  m_mrr_mode= mrr_mode;
+  m_mrr_n_ranges= n_ranges;
+  DBUG_RETURN(0);
+
+error:
+  DBUG_RETURN(error);
+}
+
+
+int ha_partition::multi_range_read_next(range_id_t *range_info)
+{
+  int error;
+  DBUG_ENTER("ha_partition::multi_range_read_next");
+  DBUG_PRINT("enter", ("partition this: %p  partition m_mrr_mode: %u",
+                       this, m_mrr_mode));
+
+  if ((m_mrr_mode & HA_MRR_SORTED))
+  {
+    if (m_multi_range_read_first)
+    {
+      if (unlikely((error= handle_ordered_index_scan(table->record[0],
+                                                     FALSE))))
+        DBUG_RETURN(error);
+      if (!m_pre_calling)
+        m_multi_range_read_first= FALSE;
+    }
+    else if (unlikely((error= handle_ordered_next(table->record[0],
+                                                  eq_range))))
+      DBUG_RETURN(error);
+    *range_info= m_mrr_range_current->ptr;
+  }
+  else
+  {
+    if (unlikely(m_multi_range_read_first))
+    {
+      if (unlikely((error=
+                    handle_unordered_scan_next_partition(table->record[0]))))
+        DBUG_RETURN(error);
+      if (!m_pre_calling)
+        m_multi_range_read_first= FALSE;
+    }
+    else if (unlikely((error= handle_unordered_next(table->record[0], FALSE))))
+      DBUG_RETURN(error);
+
+    if (!(m_mrr_mode & HA_MRR_NO_ASSOCIATION))
+    {
+      *range_info=
+        ((PARTITION_KEY_MULTI_RANGE *) m_range_info[m_last_part])->ptr;
+    }
+  }
+  DBUG_RETURN(0);
+}
+
+
+int ha_partition::multi_range_read_explain_info(uint mrr_mode, char *str,
+                                                size_t size)
+{
+  DBUG_ENTER("ha_partition::multi_range_read_explain_info");
+  DBUG_RETURN(get_open_file_sample()->
+                multi_range_read_explain_info(mrr_mode, str, size));
+}
+
+
+/**
+  Find and retrieve the Full Text Search relevance ranking for a search string
+  in a full text index.
+
+  @param  handler           Full Text Search handler
+  @param  record            Search string
+  @param  length            Length of the search string
+
+  @retval                   Relevance value
+*/
+
+float partition_ft_find_relevance(FT_INFO *handler,
+                                  uchar *record, uint length)
+{
+  st_partition_ft_info *info= (st_partition_ft_info *)handler;
+  uint m_last_part= ((ha_partition*) info->file)->last_part();
+  FT_INFO *m_handler= info->part_ft_info[m_last_part];
+  DBUG_ENTER("partition_ft_find_relevance");
+  if (!m_handler)
+    DBUG_RETURN((float)-1.0);
+  DBUG_RETURN(m_handler->please->find_relevance(m_handler, record, length));
+}
+
+
+/**
+  Retrieve the Full Text Search relevance ranking for the current
+  full text search.
+
+  @param  handler           Full Text Search handler
+
+  @retval                   Relevance value
+*/
+
+float partition_ft_get_relevance(FT_INFO *handler)
+{
+  st_partition_ft_info *info= (st_partition_ft_info *)handler;
+  uint m_last_part= ((ha_partition*) info->file)->last_part();
+  FT_INFO *m_handler= info->part_ft_info[m_last_part];
+  DBUG_ENTER("partition_ft_get_relevance");
+  if (!m_handler)
+    DBUG_RETURN((float)-1.0);
+  DBUG_RETURN(m_handler->please->get_relevance(m_handler));
+}
+
+
+/**
+  Free the memory for a full text search handler.
+
+  @param  handler           Full Text Search handler
+*/
+
+void partition_ft_close_search(FT_INFO *handler)
+{
+  st_partition_ft_info *info= (st_partition_ft_info *)handler;
+  info->file->ft_close_search(handler);
+}
+
+
+/**
+  Free the memory for a full text search handler.
+
+  @param  handler           Full Text Search handler
+*/
+
+void ha_partition::ft_close_search(FT_INFO *handler)
+{
+  uint i;
+  st_partition_ft_info *info= (st_partition_ft_info *)handler;
+  DBUG_ENTER("ha_partition::ft_close_search");
+
+  for (i= 0; i < m_tot_parts; i++)
+  {
+    FT_INFO *m_handler= info->part_ft_info[i];
+    DBUG_ASSERT(!m_handler ||
+                (m_handler->please && m_handler->please->close_search));
+    if (m_handler &&
+        m_handler->please &&
+        m_handler->please->close_search)
+      m_handler->please->close_search(m_handler);
+  }
+  DBUG_VOID_RETURN;
+}
+
+
+/* Partition Full Text search function table */
+_ft_vft partition_ft_vft =
+{
+  NULL, // partition_ft_read_next
+  partition_ft_find_relevance,
+  partition_ft_close_search,
+  partition_ft_get_relevance,
+  NULL  // partition_ft_reinit_search
+};
+
+
+/**
+  Initialize a full text search.
+*/
+
+int ha_partition::ft_init()
+{
+  int error;
+  uint i= 0;
+  uint32 part_id;
+  DBUG_ENTER("ha_partition::ft_init");
+  DBUG_PRINT("info", ("partition this: %p", this));
+
+  /*
+    For operations that may need to change data, we may need to extend
+    read_set.
+  */
+  if (get_lock_type() == F_WRLCK)
+  {
+    /*
+      If write_set contains any of the fields used in partition and
+      subpartition expression, we need to set all bits in read_set because
+      the row may need to be inserted in a different [sub]partition. In
+      other words update_row() can be converted into write_row(), which
+      requires a complete record.
+    */
+    if (bitmap_is_overlapping(&m_part_info->full_part_field_set,
+                              table->write_set))
+      bitmap_set_all(table->read_set);
+    else
+    {
+      /*
+        Some handlers only read fields as specified by the bitmap for the
+        read set. For partitioned handlers we always require that the
+        fields of the partition functions are read such that we can
+        calculate the partition id to place updated and deleted records.
+      */
+      bitmap_union(table->read_set, &m_part_info->full_part_field_set);
+    }
+  }
+
+  /* Now we see what the index of our first important partition is */
+  DBUG_PRINT("info", ("m_part_info->read_partitions: %p",
+             (void *) m_part_info->read_partitions.bitmap));
+  part_id= bitmap_get_first_set(&(m_part_info->read_partitions));
+  DBUG_PRINT("info", ("m_part_spec.start_part %u", (uint) part_id));
+
+  if (part_id == MY_BIT_NONE)
+  {
+    error= 0;
+    goto err1;
+  }
+
+  DBUG_PRINT("info", ("ft_init on partition %u", (uint) part_id));
+  /*
+    ft_end() is needed for partitioning to reset internal data if scan
+    is already in use
+  */
+  if (m_pre_calling)
+  {
+    if (unlikely((error= pre_ft_end())))
+      goto err1;
+  }
+  else
+    ft_end();
+  m_index_scan_type= partition_ft_read;
+  for (i= part_id; i < m_tot_parts; i++)
+  {
+    if (bitmap_is_set(&(m_part_info->read_partitions), i))
+    {
+      error= m_pre_calling ? m_file[i]->pre_ft_init() : m_file[i]->ft_init();
+      if (unlikely(error))
+        goto err2;
+    }
+  }
+  m_scan_value= 1;
+  m_part_spec.start_part= part_id;
+  m_part_spec.end_part= m_tot_parts - 1;
+  m_ft_init_and_first= TRUE;
+  DBUG_PRINT("info", ("m_scan_value: %u", m_scan_value));
+  DBUG_RETURN(0);
+
+err2:
+  late_extra_no_cache(part_id);
+  while ((int)--i >= (int)part_id)
+  {
+    if (bitmap_is_set(&(m_part_info->read_partitions), i))
+    {
+      if (m_pre_calling)
+        m_file[i]->pre_ft_end();
+      else
+        m_file[i]->ft_end();
+    }
+  }
+err1:
+  m_scan_value= 2;
+  m_part_spec.start_part= NO_CURRENT_PART_ID;
+  DBUG_RETURN(error);
+}
+
+
+/**
+  Initialize a full text search during a bulk access request.
+*/
+
+int ha_partition::pre_ft_init()
+{
+  bool save_m_pre_calling;
+  int error;
+  DBUG_ENTER("ha_partition::pre_ft_init");
+  save_m_pre_calling= m_pre_calling;
+  m_pre_calling= TRUE;
+  error= ft_init();
+  m_pre_calling= save_m_pre_calling;
+  DBUG_RETURN(error);
+}
+
+
+/**
+  Terminate a full text search.
+*/
+
+void ha_partition::ft_end()
+{
+  handler **file;
+  DBUG_ENTER("ha_partition::ft_end");
+  DBUG_PRINT("info", ("partition this: %p", this));
+
+  switch (m_scan_value) {
+  case 2:                                       // Error
+    break;
+  case 1:                                       // Table scan
+    if (NO_CURRENT_PART_ID != m_part_spec.start_part)
+      late_extra_no_cache(m_part_spec.start_part);
+    file= m_file;
+    do
+    {
+      if (bitmap_is_set(&(m_part_info->read_partitions), (uint)(file - m_file)))
+      {
+        if (m_pre_calling)
+          (*file)->pre_ft_end();
+        else
+          (*file)->ft_end();
+      }
+    } while (*(++file));
+    break;
+  }
+  m_scan_value= 2;
+  m_part_spec.start_part= NO_CURRENT_PART_ID;
+  ft_current= 0;
+  DBUG_VOID_RETURN;
+}
+
+
+/**
+  Terminate a full text search during a bulk access request.
+*/
+
+int ha_partition::pre_ft_end()
+{
+  bool save_m_pre_calling;
+  DBUG_ENTER("ha_partition::pre_ft_end");
+  save_m_pre_calling= m_pre_calling;
+  m_pre_calling= TRUE;
+  ft_end();
+  m_pre_calling= save_m_pre_calling;
+  DBUG_RETURN(0);
+}
+
+
+/**
+  Initialize a full text search using the extended API.
+
+  @param  flags             Search flags
+  @param  inx               Key number
+  @param  key               Key value
+
+  @return FT_INFO structure if successful
+          NULL              otherwise
+*/
+
+FT_INFO *ha_partition::ft_init_ext(uint flags, uint inx, String *key)
+{
+  FT_INFO *ft_handler;
+  handler **file;
+  st_partition_ft_info *ft_target, **parent;
+  DBUG_ENTER("ha_partition::ft_init_ext");
+
+  if (ft_current)
+    parent= &ft_current->next;
+  else
+    parent= &ft_first;
+
+  if (!(ft_target= *parent))
+  {
+    FT_INFO **tmp_ft_info;
+    if (!(ft_target= (st_partition_ft_info *)
+          my_multi_malloc(PSI_INSTRUMENT_ME, MYF(MY_WME | MY_ZEROFILL),
+                          &ft_target, sizeof(st_partition_ft_info),
+                          &tmp_ft_info, sizeof(FT_INFO *) * m_tot_parts,
+                          NullS)))
+    {
+      my_error(ER_OUT_OF_RESOURCES, MYF(ME_FATAL));
+      DBUG_RETURN(NULL);
+    }
+    ft_target->part_ft_info= tmp_ft_info;
+    (*parent)= ft_target;
+  }
+
+  ft_current= ft_target;
+  file= m_file;
+  do
+  {
+    if (bitmap_is_set(&(m_part_info->read_partitions), (uint)(file - m_file)))
+    {
+      if ((ft_handler= (*file)->ft_init_ext(flags, inx, key)))
+        (*file)->ft_handler= ft_handler;
+      else
+        (*file)->ft_handler= NULL;
+      ft_target->part_ft_info[file - m_file]= ft_handler;
+    }
+    else
+    {
+      (*file)->ft_handler= NULL;
+      ft_target->part_ft_info[file - m_file]= NULL;
+    }
+  } while (*(++file));
+
+  ft_target->please= &partition_ft_vft;
+  ft_target->file= this;
+  DBUG_RETURN((FT_INFO*)ft_target);
+}
+
+
+/**
+  Return the next record from the FT result set during an ordered index
+  pre-scan
+
+  @param  use_parallel      Is it a parallel search
+
+  @return >0                Error code
+          0                 Success
+*/
+
+int ha_partition::pre_ft_read(bool use_parallel)
+{
+  bool save_m_pre_calling;
+  int error;
+  DBUG_ENTER("ha_partition::pre_ft_read");
+  DBUG_PRINT("info", ("partition this: %p", this));
+  save_m_pre_calling= m_pre_calling;
+  m_pre_calling= TRUE;
+  m_pre_call_use_parallel= use_parallel;
+  error= ft_read(table->record[0]);
+  m_pre_calling= save_m_pre_calling;
+  DBUG_RETURN(error);
+}
+
+
+/**
+  Return the first or next record in a full text search.
+
+  @param  buf               Buffer where the record should be returned
+
+  @return >0                Error code
+          0                 Success
+*/
+
+int ha_partition::ft_read(uchar *buf)
+{
+  handler *file;
+  int result= HA_ERR_END_OF_FILE, error;
+  uint part_id= m_part_spec.start_part;
+  DBUG_ENTER("ha_partition::ft_read");
+  DBUG_PRINT("info", ("partition this: %p", this));
+  DBUG_PRINT("info", ("part_id: %u", part_id));
+
+  if (part_id == NO_CURRENT_PART_ID)
+  {
+    /*
+      The original set of partitions to scan was empty and thus we report
+      the result here.
+    */
+    DBUG_PRINT("info", ("NO_CURRENT_PART_ID"));
+    goto end;
+  }
+
+  DBUG_ASSERT(m_scan_value == 1);
+
+  if (m_ft_init_and_first)                      // First call to ft_read()
+  {
+    m_ft_init_and_first= FALSE;
+    if (!bulk_access_executing)
+    {
+      error= handle_pre_scan(FALSE, check_parallel_search());
+      if (m_pre_calling || error)
+        DBUG_RETURN(error);
+    }
+    late_extra_cache(part_id);
+  }
+
+  file= m_file[part_id];
+
+  while (TRUE)
+  {
+    if (!(result= file->ft_read(buf)))
+    {
+      /* Found row: remember position and return it. */
+      m_part_spec.start_part= m_last_part= part_id;
+      table->status= 0;
+      DBUG_RETURN(0);
+    }
+
+    /*
+      if we get here, then the current partition ft_next returned failure
+    */
+    if (result != HA_ERR_END_OF_FILE)
+      goto end_dont_reset_start_part;         // Return error
+
+    /* End current partition */
+    late_extra_no_cache(part_id);
+    DBUG_PRINT("info", ("stopping using partition %u", (uint) part_id));
+
+    /* Shift to next partition */
+    while (++part_id < m_tot_parts &&
+           !bitmap_is_set(&(m_part_info->read_partitions), part_id))
+      ;
+    if (part_id >= m_tot_parts)
+    {
+      result= HA_ERR_END_OF_FILE;
+      break;
+    }
+    m_part_spec.start_part= m_last_part= part_id;
+    file= m_file[part_id];
+    DBUG_PRINT("info", ("now using partition %u", (uint) part_id));
+    late_extra_cache(part_id);
+  }
+
+end:
+  m_part_spec.start_part= NO_CURRENT_PART_ID;
+end_dont_reset_start_part:
+  table->status= STATUS_NOT_FOUND;
+  DBUG_RETURN(result);
+}
+
+
+/*
+  Common routine to set up index scans
+
+  SYNOPSIS
+    ha_partition::partition_scan_set_up()
+      buf            Buffer to later return record in (this function
+                     needs it to calculcate partitioning function
+                     values)
+
+      idx_read_flag  TRUE <=> m_start_key has range start endpoint which
+                     probably can be used to determine the set of partitions
+                     to scan.
+                     FALSE <=> there is no start endpoint.
+
+  DESCRIPTION
+    Find out which partitions we'll need to read when scanning the specified
+    range.
+
+    If we need to scan only one partition, set m_ordered_scan_ongoing=FALSE
+    as we will not need to do merge ordering.
+
+  RETURN VALUE
+    >0                    Error code
+    0                     Success
+*/
+
+int ha_partition::partition_scan_set_up(uchar * buf, bool idx_read_flag)
+{
+  DBUG_ENTER("ha_partition::partition_scan_set_up");
+
+  if (idx_read_flag)
+    get_partition_set(table, buf, active_index, &m_start_key, &m_part_spec);
+  else
+  {
+    m_part_spec.start_part= 0;
+    m_part_spec.end_part= m_tot_parts - 1;
+  }
+  if (m_part_spec.start_part > m_part_spec.end_part)
+  {
+    /*
+      We discovered a partition set but the set was empty so we report
+      key not found.
+    */
+    DBUG_PRINT("info", ("scan with no partition to scan"));
+    DBUG_RETURN(HA_ERR_END_OF_FILE);
+  }
+  if (m_part_spec.start_part == m_part_spec.end_part)
+  {
+    /*
+      We discovered a single partition to scan, this never needs to be
+      performed using the ordered index scan.
+    */
+    DBUG_PRINT("info", ("index scan using the single partition %u",
+			(uint) m_part_spec.start_part));
+    m_ordered_scan_ongoing= FALSE;
+  }
+  else
+  {
+    /*
+      Set m_ordered_scan_ongoing according how the scan should be done
+      Only exact partitions are discovered atm by get_partition_set.
+      Verify this, also bitmap must have at least one bit set otherwise
+      the result from this table is the empty set.
+    */
+    uint start_part= bitmap_get_first_set(&(m_part_info->read_partitions));
+    if (start_part == MY_BIT_NONE)
+    {
+      DBUG_PRINT("info", ("scan with no partition to scan"));
+      DBUG_RETURN(HA_ERR_END_OF_FILE);
+    }
+    if (start_part > m_part_spec.start_part)
+      m_part_spec.start_part= start_part;
+    DBUG_ASSERT(m_part_spec.start_part < m_tot_parts);
+    m_ordered_scan_ongoing= m_ordered;
+  }
+  DBUG_ASSERT(m_part_spec.start_part < m_tot_parts);
+  DBUG_ASSERT(m_part_spec.end_part < m_tot_parts);
+  DBUG_RETURN(0);
+}
+
+/**
+  Check if we can search partitions in parallel
+
+  @retval TRUE  yes
+  @retval FALSE no
+*/
+
+bool ha_partition::check_parallel_search()
+{
+  TABLE_LIST *table_list= table->pos_in_table_list;
+  st_select_lex *select_lex;
+  JOIN *join;
+  DBUG_ENTER("ha_partition::check_parallel_search");
+  if (!table_list)
+    goto not_parallel;
+
+  while (table_list->parent_l)
+    table_list= table_list->parent_l;
+
+  select_lex= table_list->select_lex;
+  DBUG_PRINT("info",("partition select_lex: %p", select_lex));
+  if (!select_lex)
+    goto not_parallel;
+  if (!select_lex->explicit_limit)
+  {
+    DBUG_PRINT("info",("partition not using explicit_limit"));
+    goto parallel;
+  }
+
+  join= select_lex->join;
+  DBUG_PRINT("info",("partition join: %p", join));
+  if (join && join->skip_sort_order)
+  {
+    DBUG_PRINT("info",("partition order_list.elements: %u",
+                       select_lex->order_list.elements));
+    if (select_lex->order_list.elements)
+    {
+      Item *item= *select_lex->order_list.first->item;
+      DBUG_PRINT("info",("partition item: %p", item));
+      DBUG_PRINT("info",("partition item->type(): %u", item->type()));
+      DBUG_PRINT("info",("partition m_part_info->part_type: %u",
+                         m_part_info->part_type));
+      DBUG_PRINT("info",("partition m_is_sub_partitioned: %s",
+                         m_is_sub_partitioned ? "TRUE" : "FALSE"));
+      DBUG_PRINT("info",("partition m_part_info->part_expr: %p",
+                         m_part_info->part_expr));
+      if (item->type() == Item::FIELD_ITEM &&
+          m_part_info->part_type == RANGE_PARTITION &&
+          !m_is_sub_partitioned &&
+          (!m_part_info->part_expr ||
+           m_part_info->part_expr->type() == Item::FIELD_ITEM))
+      {
+        Field *order_field= ((Item_field *)item)->field;
+        DBUG_PRINT("info",("partition order_field: %p", order_field));
+        if (order_field && order_field->table == table_list->table)
+        {
+          Field *part_field= m_part_info->full_part_field_array[0];
+          DBUG_PRINT("info",("partition order_field: %p", order_field));
+          DBUG_PRINT("info",("partition part_field: %p", part_field));
+          if (part_field == order_field)
+          {
+            /*
+              We are using ORDER BY partition_field LIMIT #
+              In this case, let's not do things in parallel as it's
+              likely that the query can be satisfied from the first
+              partition
+            */
+            DBUG_PRINT("info",("partition with ORDER on partition field"));
+            goto not_parallel;
+          }
+        }
+      }
+      DBUG_PRINT("info",("partition have order"));
+      goto parallel;
+    }
+
+    DBUG_PRINT("info",("partition group_list.elements: %u",
+                       select_lex->group_list.elements));
+    if (select_lex->group_list.elements)
+    {
+      Item *item= *select_lex->group_list.first->item;
+      DBUG_PRINT("info",("partition item: %p", item));
+      DBUG_PRINT("info",("partition item->type(): %u", item->type()));
+      DBUG_PRINT("info",("partition m_part_info->part_type: %u",
+                         m_part_info->part_type));
+      DBUG_PRINT("info",("partition m_is_sub_partitioned: %s",
+                         m_is_sub_partitioned ? "TRUE" : "FALSE"));
+      DBUG_PRINT("info",("partition m_part_info->part_expr: %p",
+                         m_part_info->part_expr));
+      if (item->type() == Item::FIELD_ITEM &&
+          m_part_info->part_type == RANGE_PARTITION &&
+          !m_is_sub_partitioned &&
+          (!m_part_info->part_expr ||
+           m_part_info->part_expr->type() == Item::FIELD_ITEM))
+      {
+        Field *group_field= ((Item_field *)item)->field;
+        DBUG_PRINT("info",("partition group_field: %p", group_field));
+        if (group_field && group_field->table == table_list->table)
+        {
+          Field *part_field= m_part_info->full_part_field_array[0];
+          DBUG_PRINT("info",("partition group_field: %p", group_field));
+          DBUG_PRINT("info",("partition part_field: %p", part_field));
+          if (part_field == group_field)
+          {
+            DBUG_PRINT("info",("partition with GROUP BY on partition field"));
+            goto not_parallel;
+          }
+        }
+      }
+      DBUG_PRINT("info",("partition with GROUP BY"));
+      goto parallel;
+    }
+  }
+  else if (select_lex->order_list.elements ||
+           select_lex->group_list.elements)
+  {
+    DBUG_PRINT("info",("partition is not skip_order"));
+    DBUG_PRINT("info",("partition order_list.elements: %u",
+                       select_lex->order_list.elements));
+    DBUG_PRINT("info",("partition group_list.elements: %u",
+                       select_lex->group_list.elements));
+    goto parallel;
+  }
+  DBUG_PRINT("info",("partition is not skip_order"));
+
+not_parallel:
+  DBUG_PRINT("return",("partition FALSE"));
+  DBUG_RETURN(FALSE);
+
+parallel:
+  DBUG_PRINT("return",("partition TRUE"));
+  DBUG_RETURN(TRUE);
+}
+
+
+int ha_partition::handle_pre_scan(bool reverse_order, bool use_parallel)
+{
+  uint i;
+  DBUG_ENTER("ha_partition::handle_pre_scan");
+  DBUG_PRINT("enter",
+             ("m_part_spec.start_part: %u  m_part_spec.end_part: %u",
+              (uint) m_part_spec.start_part, (uint) m_part_spec.end_part));
+
+  for (i= m_part_spec.start_part; i <= m_part_spec.end_part; i++)
+  {
+    if (!(bitmap_is_set(&(m_part_info->read_partitions), i)))
+      continue;
+    int error;
+    handler *file= m_file[i];
+
+    switch (m_index_scan_type) {
+    case partition_index_read:
+      error= file->pre_index_read_map(m_start_key.key,
+                                  m_start_key.keypart_map,
+                                  m_start_key.flag,
+                                  use_parallel);
+      break;
+    case partition_index_first:
+      error= file->pre_index_first(use_parallel);
+      break;
+    case partition_index_last:
+      error= file->pre_index_last(use_parallel);
+      break;
+    case partition_index_read_last:
+      error= file->pre_index_read_last_map(m_start_key.key,
+                                       m_start_key.keypart_map,
+                                       use_parallel);
+      break;
+    case partition_read_range:
+      error= file->pre_read_range_first(m_start_key.key? &m_start_key: NULL,
+                                    end_range, eq_range, TRUE, use_parallel);
+      break;
+    case partition_read_multi_range:
+      if (!bitmap_is_set(&m_mrr_used_partitions, i))
+        continue;
+      error= file->pre_multi_range_read_next(use_parallel);
+      break;
+    case partition_ft_read:
+      error= file->pre_ft_read(use_parallel);
+      break;
+    case partition_no_index_scan:
+      error= file->pre_rnd_next(use_parallel);
+      break;
+    default:
+      DBUG_ASSERT(FALSE);
+      DBUG_RETURN(0);
+    }
+    if (error == HA_ERR_END_OF_FILE)
+      error= 0;
+    if (unlikely(error))
+      DBUG_RETURN(error);
+  }
+  table->status= 0;
+  DBUG_RETURN(0);
+}
+
+
+/****************************************************************************
+  Unordered Index Scan Routines
+****************************************************************************/
+/*
+  Common routine to handle index_next with unordered results
+
+  SYNOPSIS
+    handle_unordered_next()
+    out:buf                       Read row in MySQL Row Format
+    next_same                     Called from index_next_same
+
+  RETURN VALUE
+    HA_ERR_END_OF_FILE            End of scan
+    0                             Success
+    other                         Error code
+
+  DESCRIPTION
+    These routines are used to scan partitions without considering order.
+    This is performed in two situations.
+    1) In read_multi_range this is the normal case
+    2) When performing any type of index_read, index_first, index_last where
+    all fields in the partition function is bound. In this case the index
+    scan is performed on only one partition and thus it isn't necessary to
+    perform any sort.
+*/
+
+int ha_partition::handle_unordered_next(uchar *buf, bool is_next_same)
+{
+  handler *file;
+  int error;
+  DBUG_ENTER("ha_partition::handle_unordered_next");
+
+  if (m_part_spec.start_part >= m_tot_parts)
+  {
+    /* Should never happen! */
+    DBUG_ASSERT(0);
+    DBUG_RETURN(HA_ERR_END_OF_FILE);
+  }
+  file= m_file[m_part_spec.start_part];
+
+  /*
+    We should consider if this should be split into three functions as
+    partition_read_range is_next_same are always local constants
+  */
+
+  if (m_index_scan_type == partition_read_multi_range)
+  {
+    if (likely(!(error= file->
+                 multi_range_read_next(&m_range_info[m_part_spec.start_part]))))
+    {
+      m_last_part= m_part_spec.start_part;
+      DBUG_RETURN(0);
+    }
+  }
+  else if (m_index_scan_type == partition_read_range)
+  {
+    if (likely(!(error= file->read_range_next())))
+    {
+      m_last_part= m_part_spec.start_part;
+      DBUG_RETURN(0);
+    }
+  }
+  else if (is_next_same)
+  {
+    if (likely(!(error= file->ha_index_next_same(buf, m_start_key.key,
+                                                 m_start_key.length))))
+    {
+      m_last_part= m_part_spec.start_part;
+      DBUG_RETURN(0);
+    }
+  }
+  else
+  {
+    if (likely(!(error= file->ha_index_next(buf))))
+    {
+      m_last_part= m_part_spec.start_part;
+      DBUG_RETURN(0);                           // Row was in range
+    }
+  }
+
+    if (unlikely(error == HA_ERR_END_OF_FILE))
+  {
+    m_part_spec.start_part++;                    // Start using next part
+    error= handle_unordered_scan_next_partition(buf);
+  }
+  DBUG_RETURN(error);
+}
+
+
+/*
+  Handle index_next when changing to new partition
+
+  SYNOPSIS
+    handle_unordered_scan_next_partition()
+    buf                       Read row in MariaDB Row Format
+
+  RETURN VALUE
+    HA_ERR_END_OF_FILE            End of scan
+    0                             Success
+    other                         Error code
+
+  DESCRIPTION
+    This routine is used to start the index scan on the next partition.
+    Both initial start and after completing scan on one partition.
+*/
+
+int ha_partition::handle_unordered_scan_next_partition(uchar * buf)
+{
+  uint i= m_part_spec.start_part;
+  int saved_error= HA_ERR_END_OF_FILE;
+  DBUG_ENTER("ha_partition::handle_unordered_scan_next_partition");
+
+  /* Read next partition that includes start_part */
+  if (i)
+    i= bitmap_get_next_set(&m_part_info->read_partitions, i - 1);
+  else
+    i= bitmap_get_first_set(&m_part_info->read_partitions);
+
+  for (;
+       i <= m_part_spec.end_part;
+       i= bitmap_get_next_set(&m_part_info->read_partitions, i))
+  {
+    int error;
+    handler *file= m_file[i];
+    m_part_spec.start_part= i;
+
+    switch (m_index_scan_type) {
+    case partition_read_multi_range:
+      if (!bitmap_is_set(&m_mrr_used_partitions, i))
+        continue;
+      DBUG_PRINT("info", ("read_multi_range on partition %u", i));
+      error= file->multi_range_read_next(&m_range_info[i]);
+      break;
+    case partition_read_range:
+      DBUG_PRINT("info", ("read_range_first on partition %u", i));
+      error= file->read_range_first(m_start_key.key? &m_start_key: NULL,
+                                    end_range, eq_range, FALSE);
+      break;
+    case partition_index_read:
+      DBUG_PRINT("info", ("index_read on partition %u", i));
+      error= file->ha_index_read_map(buf, m_start_key.key,
+                                     m_start_key.keypart_map,
+                                     m_start_key.flag);
+      break;
+    case partition_index_first:
+      DBUG_PRINT("info", ("index_first on partition %u", i));
+      error= file->ha_index_first(buf);
+      break;
+    default:
+      DBUG_ASSERT(FALSE);
+      DBUG_RETURN(1);
+    }
+    if (likely(!error))
+    {
+      m_last_part= i;
+      DBUG_RETURN(0);
+    }
+    if (likely((error != HA_ERR_END_OF_FILE) &&
+               (error != HA_ERR_KEY_NOT_FOUND)))
+      DBUG_RETURN(error);
+
+    /*
+      If HA_ERR_KEY_NOT_FOUND, we must return that error instead of
+      HA_ERR_END_OF_FILE, to be able to continue search.
+    */
+    if (saved_error != HA_ERR_KEY_NOT_FOUND)
+      saved_error= error;
+    DBUG_PRINT("info", ("END_OF_FILE/KEY_NOT_FOUND on partition %u", i));
+  }
+  if (saved_error == HA_ERR_END_OF_FILE)
+    m_part_spec.start_part= NO_CURRENT_PART_ID;
+  DBUG_RETURN(saved_error);
+}
+
+
+/**
+  Common routine to start index scan with ordered results.
+
+  @param[out] buf  Read row in MariaDB Row Format
+
+  @return Operation status
+    @retval HA_ERR_END_OF_FILE  End of scan
+    @retval HA_ERR_KEY_NOT_FOUNE  End of scan
+    @retval 0                   Success
+    @retval other               Error code
+
+  @details
+    This part contains the logic to handle index scans that require ordered
+    output. This includes all except those started by read_range_first with
+    the flag ordered set to FALSE. Thus most direct index_read and all
+    index_first and index_last.
+
+    We implement ordering by keeping one record plus a key buffer for each
+    partition. Every time a new entry is requested we will fetch a new
+    entry from the partition that is currently not filled with an entry.
+    Then the entry is put into its proper sort position.
+
+    Returning a record is done by getting the top record, copying the
+    record to the request buffer and setting the partition as empty on
+    entries.
+*/
+
+int ha_partition::handle_ordered_index_scan(uchar *buf, bool reverse_order)
+{
+  int error;
+  uint i;
+  uint j= queue_first_element(&m_queue);
+  uint smallest_range_seq= 0;
+  bool found= FALSE;
+  uchar *part_rec_buf_ptr= m_ordered_rec_buffer;
+  int saved_error= HA_ERR_END_OF_FILE;
+  DBUG_ENTER("ha_partition::handle_ordered_index_scan");
+  DBUG_PRINT("enter", ("partition this: %p", this));
+
+   if (m_pre_calling)
+     error= handle_pre_scan(reverse_order, m_pre_call_use_parallel);
+   else
+     error= handle_pre_scan(reverse_order, check_parallel_search());
+   if (unlikely(error))
+    DBUG_RETURN(error);
+
+  if (m_key_not_found)
+  {
+    /* m_key_not_found was set in the previous call to this function */
+    m_key_not_found= false;
+    bitmap_clear_all(&m_key_not_found_partitions);
+  }
+  m_top_entry= NO_CURRENT_PART_ID;
+  DBUG_PRINT("info", ("partition queue_remove_all(1)"));
+  queue_remove_all(&m_queue);
+  DBUG_ASSERT(bitmap_is_set(&m_part_info->read_partitions,
+                            m_part_spec.start_part));
+
+  /*
+    Position part_rec_buf_ptr to point to the first used partition >=
+    start_part. There may be partitions marked by used_partitions,
+    but is before start_part. These partitions has allocated record buffers
+    but is dynamically pruned, so those buffers must be skipped.
+  */
+  for (i= bitmap_get_first_set(&m_part_info->read_partitions);
+       i < m_part_spec.start_part;
+       i= bitmap_get_next_set(&m_part_info->read_partitions, i))
+  {
+    part_rec_buf_ptr+= m_priority_queue_rec_len;
+  }
+  DBUG_PRINT("info", ("m_part_spec.start_part %u first_used_part %u",
+                      m_part_spec.start_part, i));
+  for (/* continue from above */ ;
+       i <= m_part_spec.end_part ;
+       i= bitmap_get_next_set(&m_part_info->read_partitions, i),
+       part_rec_buf_ptr+= m_priority_queue_rec_len)
+  {
+    DBUG_PRINT("info", ("reading from part %u (scan_type: %u)",
+                        i, m_index_scan_type));
+    DBUG_ASSERT(i == uint2korr(part_rec_buf_ptr));
+    uchar *rec_buf_ptr= part_rec_buf_ptr + PARTITION_BYTES_IN_POS;
+    handler *file= m_file[i];
+
+    switch (m_index_scan_type) {
+    case partition_index_read:
+      error= file->ha_index_read_map(rec_buf_ptr,
+                                     m_start_key.key,
+                                     m_start_key.keypart_map,
+                                     m_start_key.flag);
+      /* Caller has specified reverse_order */
+      break;
+    case partition_index_first:
+      error= file->ha_index_first(rec_buf_ptr);
+      reverse_order= FALSE;
+      break;
+    case partition_index_last:
+      error= file->ha_index_last(rec_buf_ptr);
+      reverse_order= TRUE;
+      break;
+    case partition_read_range:
+    {
+      /*
+        This can only read record to table->record[0], as it was set when
+        the table was being opened. We have to memcpy data ourselves.
+      */
+      error= file->read_range_first(m_start_key.key? &m_start_key: NULL,
+                                    end_range, eq_range, TRUE);
+      if (likely(!error))
+        memcpy(rec_buf_ptr, table->record[0], m_rec_length);
+      reverse_order= FALSE;
+      break;
+    }
+    case partition_read_multi_range:
+    {
+      if (!bitmap_is_set(&m_mrr_used_partitions, i))
+        continue;
+      DBUG_PRINT("info", ("partition %u", i));
+      error= file->multi_range_read_next(&m_range_info[i]);
+      DBUG_PRINT("info", ("error: %d", error));
+      if (error == HA_ERR_KEY_NOT_FOUND || error == HA_ERR_END_OF_FILE)
+      {
+        bitmap_clear_bit(&m_mrr_used_partitions, i);
+        continue;
+      }
+      if (likely(!error))
+      {
+        memcpy(rec_buf_ptr, table->record[0], m_rec_length);
+        reverse_order= FALSE;
+        m_stock_range_seq[i]= (((PARTITION_KEY_MULTI_RANGE *)
+                                m_range_info[i])->id);
+        /* Test if the key is in the first key range */
+        if (m_stock_range_seq[i] != m_mrr_range_current->id)
+        {
+          /*
+            smallest_range_seq contains the smallest key range we have seen
+            so far
+          */
+          if (!smallest_range_seq || smallest_range_seq > m_stock_range_seq[i])
+            smallest_range_seq= m_stock_range_seq[i];
+          continue;
+        }
+      }
+      break;
+    }
+    default:
+      DBUG_ASSERT(FALSE);
+      DBUG_RETURN(HA_ERR_END_OF_FILE);
+    }
+    if (likely(!error))
+    {
+      found= TRUE;
+      if (!m_using_extended_keys)
+      {
+        file->position(rec_buf_ptr);
+        memcpy(rec_buf_ptr + m_rec_length, file->ref, file->ref_length);
+      }
+      /*
+        Initialize queue without order first, simply insert
+      */
+      queue_element(&m_queue, j++)= part_rec_buf_ptr;
+    }
+    else if (error == HA_ERR_KEY_NOT_FOUND)
+    {
+      DBUG_PRINT("info", ("HA_ERR_KEY_NOT_FOUND from partition %u", i));
+      bitmap_set_bit(&m_key_not_found_partitions, i);
+      m_key_not_found= true;
+      saved_error= error;
+    }
+    else if (error != HA_ERR_END_OF_FILE)
+    {
+      DBUG_RETURN(error);
+    }
+  }
+
+  if (!found && smallest_range_seq)
+  {
+    /* We know that there is an existing row based on code above */
+    found= TRUE;
+    part_rec_buf_ptr= m_ordered_rec_buffer;
+
+    /*
+      No key found in the first key range
+      Collect all partitions that has a key in smallest_range_seq
+     */
+    DBUG_PRINT("info", ("partition !found && smallest_range_seq"));
+    for (i= bitmap_get_first_set(&m_part_info->read_partitions);
+         i <= m_part_spec.end_part;
+         i= bitmap_get_next_set(&m_part_info->read_partitions, i))
+    {
+      DBUG_PRINT("info", ("partition current_part: %u", i));
+      if (i < m_part_spec.start_part)
+      {
+        part_rec_buf_ptr+= m_priority_queue_rec_len;
+        DBUG_PRINT("info", ("partition i < m_part_spec.start_part"));
+        continue;
+      }
+      if (!bitmap_is_set(&m_mrr_used_partitions, i))
+      {
+        part_rec_buf_ptr+= m_priority_queue_rec_len;
+        DBUG_PRINT("info", ("partition !bitmap_is_set(&m_mrr_used_partitions, i)"));
+        continue;
+      }
+      DBUG_ASSERT(i == uint2korr(part_rec_buf_ptr));
+      if (smallest_range_seq == m_stock_range_seq[i])
+      {
+        m_stock_range_seq[i]= 0;
+        queue_element(&m_queue, j++)= (uchar *) part_rec_buf_ptr;
+        DBUG_PRINT("info", ("partition smallest_range_seq == m_stock_range_seq[i]"));
+      }
+      part_rec_buf_ptr+= m_priority_queue_rec_len;
+    }
+
+    /* Update global m_mrr_range_current to the current range */
+    while (m_mrr_range_current->id < smallest_range_seq)
+      m_mrr_range_current= m_mrr_range_current->next;
+  }
+  if (found)
+  {
+    /*
+      We found at least one partition with data, now sort all entries and
+      after that read the first entry and copy it to the buffer to return in.
+    */
+    queue_set_max_at_top(&m_queue, reverse_order);
+    queue_set_cmp_arg(&m_queue, (void*) this);
+    m_queue.elements= j - queue_first_element(&m_queue);
+    queue_fix(&m_queue);
+    return_top_record(buf);
+    DBUG_PRINT("info", ("Record returned from partition %u", m_top_entry));
+    DBUG_RETURN(0);
+  }
+  DBUG_RETURN(saved_error);
+}
+
+
+/*
+  Return the top record in sort order
+
+  SYNOPSIS
+    return_top_record()
+    out:buf                  Row returned in MySQL Row Format
+
+  RETURN VALUE
+    NONE
+*/
+
+void ha_partition::return_top_record(uchar *buf)
+{
+  uint part_id;
+  uchar *key_buffer= queue_top(&m_queue);
+  uchar *rec_buffer= key_buffer + PARTITION_BYTES_IN_POS;
+  DBUG_ENTER("ha_partition::return_top_record");
+  DBUG_PRINT("enter", ("partition this: %p", this));
+
+  part_id= uint2korr(key_buffer);
+  memcpy(buf, rec_buffer, m_rec_length);
+  m_last_part= part_id;
+  DBUG_PRINT("info", ("partition m_last_part: %u", m_last_part));
+  m_top_entry= part_id;
+  table->status= 0;                             // Found an existing row
+  m_file[part_id]->return_record_by_parent();
+  DBUG_VOID_RETURN;
+}
+
+/*
+  This function is only used if the partitioned table has own partitions.
+  This can happen if the partitioned VP engine is used (part of spider).
+*/
+
+void ha_partition::return_record_by_parent()
+{
+  m_file[m_last_part]->return_record_by_parent();
+  DBUG_ASSERT(0);
+}
+
+
+/**
+  Add index_next/prev from partitions without exact match.
+
+  If there where any partitions that returned HA_ERR_KEY_NOT_FOUND when
+  ha_index_read_map was done, those partitions must be included in the
+  following index_next/prev call.
+*/
+
+int ha_partition::handle_ordered_index_scan_key_not_found()
+{
+  int error;
+  uint i, old_elements= m_queue.elements;
+  uchar *part_buf= m_ordered_rec_buffer;
+  uchar *curr_rec_buf= NULL;
+  DBUG_ENTER("ha_partition::handle_ordered_index_scan_key_not_found");
+  DBUG_PRINT("enter", ("partition this: %p", this));
+  DBUG_ASSERT(m_key_not_found);
+  /*
+    Loop over all used partitions to get the correct offset
+    into m_ordered_rec_buffer.
+  */
+  for (i= bitmap_get_first_set(&m_part_info->read_partitions);
+       i < m_tot_parts;
+       i= bitmap_get_next_set(&m_part_info->read_partitions, i))
+  {
+    if (bitmap_is_set(&m_key_not_found_partitions, i))
+    {
+      /*
+        This partition is used and did return HA_ERR_KEY_NOT_FOUND
+        in index_read_map.
+      */
+      curr_rec_buf= part_buf + PARTITION_BYTES_IN_POS;
+      error= m_file[i]->ha_index_next(curr_rec_buf);
+      /* HA_ERR_KEY_NOT_FOUND is not allowed from index_next! */
+      DBUG_ASSERT(error != HA_ERR_KEY_NOT_FOUND);
+      if (likely(!error))
+      {
+        DBUG_PRINT("info", ("partition queue_insert(1)"));
+        queue_insert(&m_queue, part_buf);
+      }
+      else if (error != HA_ERR_END_OF_FILE && error != HA_ERR_KEY_NOT_FOUND)
+        DBUG_RETURN(error);
+    }
+    part_buf += m_priority_queue_rec_len;
+  }
+  DBUG_ASSERT(curr_rec_buf);
+  bitmap_clear_all(&m_key_not_found_partitions);
+  m_key_not_found= false;
+
+  if (m_queue.elements > old_elements)
+  {
+    /* Update m_top_entry, which may have changed. */
+    uchar *key_buffer= queue_top(&m_queue);
+    m_top_entry= uint2korr(key_buffer);
+  }
+  DBUG_RETURN(0);
+}
+
+
+/*
+  Common routine to handle index_next with ordered results
+
+  SYNOPSIS
+    handle_ordered_next()
+    out:buf                       Read row in MySQL Row Format
+    next_same                     Called from index_next_same
+
+  RETURN VALUE
+    HA_ERR_END_OF_FILE            End of scan
+    0                             Success
+    other                         Error code
+*/
+
+int ha_partition::handle_ordered_next(uchar *buf, bool is_next_same)
+{
+  int error;
+  DBUG_ENTER("ha_partition::handle_ordered_next");
+
+  if (m_top_entry == NO_CURRENT_PART_ID)
+    DBUG_RETURN(HA_ERR_END_OF_FILE);
+
+  uint part_id= m_top_entry;
+  uchar *rec_buf= queue_top(&m_queue) + PARTITION_BYTES_IN_POS;
+  handler *file;
+
+  if (m_key_not_found)
+  {
+    if (is_next_same)
+    {
+      /* Only rows which match the key. */
+      m_key_not_found= false;
+      bitmap_clear_all(&m_key_not_found_partitions);
+    }
+    else
+    {
+      /* There are partitions not included in the index record queue. */
+      uint old_elements= m_queue.elements;
+      if (unlikely((error= handle_ordered_index_scan_key_not_found())))
+        DBUG_RETURN(error);
+      /*
+        If the queue top changed, i.e. one of the partitions that gave
+        HA_ERR_KEY_NOT_FOUND in index_read_map found the next record,
+        return it.
+        Otherwise replace the old with a call to index_next (fall through).
+      */
+      if (old_elements != m_queue.elements && part_id != m_top_entry)
+      {
+        return_top_record(buf);
+        DBUG_RETURN(0);
+      }
+    }
+  }
+  if (part_id >= m_tot_parts)
+  {
+    /* This should never happen! */
+    DBUG_ASSERT(0);
+    DBUG_RETURN(HA_ERR_END_OF_FILE);
+  }
+
+  file= m_file[part_id];
+
+  if (m_index_scan_type == partition_read_range)
+  {
+    error= file->read_range_next();
+    memcpy(rec_buf, table->record[0], m_rec_length);
+  }
+  else if (m_index_scan_type == partition_read_multi_range)
+  {
+    DBUG_PRINT("info", ("partition_read_multi_range route"));
+    DBUG_PRINT("info", ("part_id: %u", part_id));
+    bool get_next= FALSE;
+    error= file->multi_range_read_next(&m_range_info[part_id]);
+    DBUG_PRINT("info", ("error: %d", error));
+    if (unlikely(error == HA_ERR_KEY_NOT_FOUND))
+      error= HA_ERR_END_OF_FILE;
+    if (unlikely(error == HA_ERR_END_OF_FILE))
+    {
+      bitmap_clear_bit(&m_mrr_used_partitions, part_id);
+      DBUG_PRINT("info", ("partition m_queue.elements: %u", m_queue.elements));
+      if (m_queue.elements)
+      {
+        DBUG_PRINT("info", ("partition queue_remove_top(1)"));
+        queue_remove_top(&m_queue);
+        if (m_queue.elements)
+        {
+          return_top_record(buf);
+          DBUG_PRINT("info", ("Record returned from partition %u (3)",
+                              m_top_entry));
+          DBUG_RETURN(0);
+        }
+      }
+      get_next= TRUE;
+    }
+    else if (likely(!error))
+    {
+      DBUG_PRINT("info", ("m_range_info[%u])->id: %u", part_id,
+                          ((PARTITION_KEY_MULTI_RANGE *)
+                           m_range_info[part_id])->id));
+      DBUG_PRINT("info", ("m_mrr_range_current->id: %u",
+                          m_mrr_range_current->id));
+      memcpy(rec_buf, table->record[0], m_rec_length);
+      if (((PARTITION_KEY_MULTI_RANGE *) m_range_info[part_id])->id !=
+          m_mrr_range_current->id)
+      {
+        m_stock_range_seq[part_id]=
+          ((PARTITION_KEY_MULTI_RANGE *) m_range_info[part_id])->id;
+        DBUG_PRINT("info", ("partition queue_remove_top(2)"));
+        queue_remove_top(&m_queue);
+        if (!m_queue.elements)
+          get_next= TRUE;
+      }
+    }
+    if (get_next)
+    {
+      DBUG_PRINT("info", ("get_next route"));
+      uint i, j= 0, smallest_range_seq= UINT_MAX32;
+      for (i= m_part_spec.start_part; i <= m_part_spec.end_part; i++)
+      {
+        if (!(bitmap_is_set(&(m_part_info->read_partitions), i)))
+          continue;
+        if (!bitmap_is_set(&m_mrr_used_partitions, i))
+          continue;
+        if (smallest_range_seq > m_stock_range_seq[i])
+          smallest_range_seq= m_stock_range_seq[i];
+      }
+
+      DBUG_PRINT("info", ("smallest_range_seq: %u", smallest_range_seq));
+      if (smallest_range_seq != UINT_MAX32)
+      {
+        uchar *part_rec_buf_ptr= m_ordered_rec_buffer;
+        DBUG_PRINT("info", ("partition queue_remove_all(2)"));
+        queue_remove_all(&m_queue);
+        DBUG_PRINT("info", ("m_part_spec.start_part: %u",
+          m_part_spec.start_part));
+
+        for (i= bitmap_get_first_set(&m_part_info->read_partitions);
+             i <= m_part_spec.end_part;
+             i= bitmap_get_next_set(&m_part_info->read_partitions, i),
+               part_rec_buf_ptr+= m_priority_queue_rec_len)
+        {
+          DBUG_PRINT("info",("partition part_id: %u", i));
+          if (i < m_part_spec.start_part)
+          {
+            DBUG_PRINT("info",("partition i < m_part_spec.start_part"));
+            continue;
+          }
+          if (!bitmap_is_set(&m_mrr_used_partitions, i))
+          {
+            DBUG_PRINT("info",("partition !bitmap_is_set(&m_mrr_used_partitions, i)"));
+            continue;
+          }
+          DBUG_PRINT("info",("partition uint2korr: %u",
+                             uint2korr(part_rec_buf_ptr)));
+          DBUG_ASSERT(i == uint2korr(part_rec_buf_ptr));
+          DBUG_PRINT("info", ("partition m_stock_range_seq[%u]: %u",
+                              i, m_stock_range_seq[i]));
+          if (smallest_range_seq == m_stock_range_seq[i])
+          {
+            m_stock_range_seq[i]= 0;
+            DBUG_PRINT("info", ("partition queue_insert(2)"));
+            queue_insert(&m_queue, part_rec_buf_ptr);
+            j++;
+          }
+        }
+        while (m_mrr_range_current->id < smallest_range_seq)
+          m_mrr_range_current= m_mrr_range_current->next;
+
+        DBUG_PRINT("info",("partition m_mrr_range_current: %p",
+                           m_mrr_range_current));
+        DBUG_PRINT("info",("partition m_mrr_range_current->id: %u",
+                           m_mrr_range_current ? m_mrr_range_current->id : 0));
+        queue_set_max_at_top(&m_queue, FALSE);
+        queue_set_cmp_arg(&m_queue, (void*) this);
+        m_queue.elements= j;
+        queue_fix(&m_queue);
+        return_top_record(buf);
+        DBUG_PRINT("info", ("Record returned from partition %u (4)",
+                            m_top_entry));
+        DBUG_RETURN(0);
+      }
+    }
+  }
+  else if (!is_next_same)
+    error= file->ha_index_next(rec_buf);
+  else
+    error= file->ha_index_next_same(rec_buf, m_start_key.key,
+                                    m_start_key.length);
+
+  if (unlikely(error))
+  {
+    if (error == HA_ERR_END_OF_FILE && m_queue.elements)
+    {
+      /* Return next buffered row */
+      DBUG_PRINT("info", ("partition queue_remove_top(3)"));
+      queue_remove_top(&m_queue);
+      if (m_queue.elements)
+      {
+         return_top_record(buf);
+         DBUG_PRINT("info", ("Record returned from partition %u (2)",
+                     m_top_entry));
+         error= 0;
+      }
+    }
+    DBUG_RETURN(error);
+  }
+
+  if (!m_using_extended_keys)
+  {
+    file->position(rec_buf);
+    memcpy(rec_buf + m_rec_length, file->ref, file->ref_length);
+  }
+
+  queue_replace_top(&m_queue);
+  return_top_record(buf);
+  DBUG_PRINT("info", ("Record returned from partition %u", m_top_entry));
+  DBUG_RETURN(0);
+}
+
+
+/*
+  Common routine to handle index_prev with ordered results
+
+  SYNOPSIS
+    handle_ordered_prev()
+    out:buf                       Read row in MySQL Row Format
+
+  RETURN VALUE
+    HA_ERR_END_OF_FILE            End of scan
+    0                             Success
+    other                         Error code
+*/
+
+int ha_partition::handle_ordered_prev(uchar *buf)
+{
+  int error;
+  DBUG_ENTER("ha_partition::handle_ordered_prev");
+  DBUG_PRINT("enter", ("partition: %p", this));
+
+  if (m_top_entry == NO_CURRENT_PART_ID)
+    DBUG_RETURN(HA_ERR_END_OF_FILE);
+
+  uint part_id= m_top_entry;
+  uchar *rec_buf= queue_top(&m_queue) + PARTITION_BYTES_IN_POS;
+  handler *file= m_file[part_id];
+
+  if (unlikely((error= file->ha_index_prev(rec_buf))))
+  {
+    if (error == HA_ERR_END_OF_FILE && m_queue.elements)
+    {
+      DBUG_PRINT("info", ("partition queue_remove_top(4)"));
+      queue_remove_top(&m_queue);
+      if (m_queue.elements)
+      {
+	return_top_record(buf);
+	DBUG_PRINT("info", ("Record returned from partition %u (2)",
+			    m_top_entry));
+        error= 0;
+      }
+    }
+    DBUG_RETURN(error);
+  }
+  queue_replace_top(&m_queue);
+  return_top_record(buf);
+  DBUG_PRINT("info", ("Record returned from partition %u", m_top_entry));
+  DBUG_RETURN(0);
+}
+
+
+/****************************************************************************
+                MODULE information calls
+****************************************************************************/
+
+/*
+  These are all first approximations of the extra, info, scan_time
+  and read_time calls
+*/
+
+/**
+  Helper function for sorting according to number of rows in descending order.
+*/
+
+int ha_partition::compare_number_of_records(ha_partition *me,
+                                            const uint32 *a,
+                                            const uint32 *b)
+{
+  handler **file= me->m_file;
+  /* Note: sorting in descending order! */
+  if (file[*a]->stats.records > file[*b]->stats.records)
+    return -1;
+  if (file[*a]->stats.records < file[*b]->stats.records)
+    return 1;
+  return 0;
+}
+
+
+/*
+  General method to gather info from handler
+
+  SYNOPSIS
+    info()
+    flag              Specifies what info is requested
+
+  RETURN VALUE
+    NONE
+
+  DESCRIPTION
+    ::info() is used to return information to the optimizer.
+    Currently this table handler doesn't implement most of the fields
+    really needed. SHOW also makes use of this data
+    Another note, if your handler doesn't provide exact record count,
+    you will probably want to have the following in your code:
+    if (records < 2)
+      records = 2;
+    The reason is that the server will optimize for cases of only a single
+    record. If in a table scan you don't know the number of records
+    it will probably be better to set records to two so you can return
+    as many records as you need.
+
+    Along with records a few more variables you may wish to set are:
+      records
+      deleted
+      data_file_length
+      index_file_length
+      delete_length
+      check_time
+    Take a look at the public variables in handler.h for more information.
+
+    Called in:
+      filesort.cc
+      ha_heap.cc
+      item_sum.cc
+      opt_sum.cc
+      sql_delete.cc
+     sql_delete.cc
+     sql_derived.cc
+      sql_select.cc
+      sql_select.cc
+      sql_select.cc
+      sql_select.cc
+      sql_select.cc
+      sql_show.cc
+      sql_show.cc
+      sql_show.cc
+      sql_show.cc
+      sql_table.cc
+      sql_union.cc
+      sql_update.cc
+
+    Some flags that are not implemented
+      HA_STATUS_POS:
+        This parameter is never used from the MySQL Server. It is checked in a
+        place in MyISAM so could potentially be used by MyISAM specific
+        programs.
+      HA_STATUS_NO_LOCK:
+      This is declared and often used. It's only used by MyISAM.
+      It means that MySQL doesn't need the absolute latest statistics
+      information. This may save the handler from doing internal locks while
+      retrieving statistics data.
+*/
+
+int ha_partition::info(uint flag)
+{
+  uint no_lock_flag= flag & HA_STATUS_NO_LOCK;
+  uint extra_var_flag= flag & HA_STATUS_VARIABLE_EXTRA;
+  DBUG_ENTER("ha_partition::info");
+
+#ifndef DBUG_OFF
+  if (bitmap_is_set_all(&(m_part_info->read_partitions)))
+    DBUG_PRINT("info", ("All partitions are used"));
+#endif /* DBUG_OFF */
+  if (flag & HA_STATUS_AUTO)
+  {
+    bool auto_inc_is_first_in_idx= (table_share->next_number_keypart == 0);
+    bool all_parts_opened= true;
+    DBUG_PRINT("info", ("HA_STATUS_AUTO"));
+    if (!table->found_next_number_field)
+      stats.auto_increment_value= 0;
+    else if (part_share->auto_inc_initialized)
+    {
+      lock_auto_increment();
+      stats.auto_increment_value= part_share->next_auto_inc_val;
+      unlock_auto_increment();
+    }
+    else
+    {
+      lock_auto_increment();
+      /* to avoid two concurrent initializations, check again when locked */
+      if (part_share->auto_inc_initialized)
+        stats.auto_increment_value= part_share->next_auto_inc_val;
+      else
+      {
+        /*
+          The auto-inc mutex in the table_share is locked, so we do not need
+          to have the handlers locked.
+          HA_STATUS_NO_LOCK is not checked, since we cannot skip locking
+          the mutex, because it is initialized.
+        */
+        handler *file, **file_array;
+        ulonglong auto_increment_value= 0;
+        file_array= m_file;
+        DBUG_PRINT("info",
+                   ("checking all partitions for auto_increment_value"));
+        do
+        {
+          if (!bitmap_is_set(&m_opened_partitions, (uint)(file_array - m_file)))
+          {
+            /*
+              Some partitions aren't opened.
+              So we can't calculate the autoincrement.
+            */
+            all_parts_opened= false;
+            break;
+          }
+          file= *file_array;
+          file->info(HA_STATUS_AUTO | no_lock_flag);
+          set_if_bigger(auto_increment_value,
+                        file->stats.auto_increment_value);
+        } while (*(++file_array));
+
+        DBUG_ASSERT(auto_increment_value);
+        stats.auto_increment_value= auto_increment_value;
+        if (all_parts_opened && auto_inc_is_first_in_idx)
+        {
+          set_if_bigger(part_share->next_auto_inc_val,
+                        auto_increment_value);
+          if (can_use_for_auto_inc_init())
+            part_share->auto_inc_initialized= true;
+          DBUG_PRINT("info", ("initializing next_auto_inc_val to %lu",
+                       (ulong) part_share->next_auto_inc_val));
+        }
+      }
+      unlock_auto_increment();
+    }
+  }
+  if (flag & HA_STATUS_VARIABLE)
+  {
+    uint i;
+    DBUG_PRINT("info", ("HA_STATUS_VARIABLE"));
+    /*
+      Calculates statistical variables
+      records:           Estimate of number records in table
+      We report sum (always at least 2 if not empty)
+      deleted:           Estimate of number holes in the table due to
+      deletes
+      We report sum
+      data_file_length:  Length of data file, in principle bytes in table
+      We report sum
+      index_file_length: Length of index file, in principle bytes in
+      indexes in the table
+      We report sum
+      delete_length: Length of free space easily used by new records in table
+      We report sum
+      mean_record_length:Mean record length in the table
+      We calculate this
+      check_time:        Time of last check (only applicable to MyISAM)
+      We report last time of all underlying handlers
+    */
+    handler *file;
+    stats.records= 0;
+    stats.deleted= 0;
+    stats.data_file_length= 0;
+    stats.index_file_length= 0;
+    stats.delete_length= 0;
+    stats.check_time= 0;
+    stats.checksum= 0;
+    stats.checksum_null= TRUE;
+    for (i= bitmap_get_first_set(&m_part_info->read_partitions);
+         i < m_tot_parts;
+         i= bitmap_get_next_set(&m_part_info->read_partitions, i))
+    {
+      file= m_file[i];
+      file->info(HA_STATUS_VARIABLE | no_lock_flag | extra_var_flag);
+      stats.records+= file->stats.records;
+      stats.deleted+= file->stats.deleted;
+      stats.data_file_length+= file->stats.data_file_length;
+      stats.index_file_length+= file->stats.index_file_length;
+      stats.delete_length+= file->stats.delete_length;
+      if (file->stats.check_time > stats.check_time)
+        stats.check_time= file->stats.check_time;
+      if (!file->stats.checksum_null)
+      {
+        stats.checksum+= file->stats.checksum;
+        stats.checksum_null= FALSE;
+      }
+    }
+    if (stats.records && stats.records < 2 &&
+        !(m_file[0]->ha_table_flags() & HA_STATS_RECORDS_IS_EXACT))
+      stats.records= 2;
+    if (stats.records > 0)
+      stats.mean_rec_length= (ulong) (stats.data_file_length / stats.records);
+    else
+      stats.mean_rec_length= 0;
+  }
+  if (flag & HA_STATUS_CONST)
+  {
+    DBUG_PRINT("info", ("HA_STATUS_CONST"));
+    /*
+      Recalculate loads of constant variables. MyISAM also sets things
+      directly on the table share object.
+
+      Check whether this should be fixed since handlers should not
+      change things directly on the table object.
+
+      Monty comment: This should NOT be changed!  It's the handlers
+      responsibility to correct table->s->keys_xxxx information if keys
+      have been disabled.
+
+      The most important parameters set here is records per key on
+      all indexes. block_size and primar key ref_length.
+
+      For each index there is an array of rec_per_key.
+      As an example if we have an index with three attributes a,b and c
+      we will have an array of 3 rec_per_key.
+      rec_per_key[0] is an estimate of number of records divided by
+      number of unique values of the field a.
+      rec_per_key[1] is an estimate of the number of records divided
+      by the number of unique combinations of the fields a and b.
+      rec_per_key[2] is an estimate of the number of records divided
+      by the number of unique combinations of the fields a,b and c.
+
+      Many handlers only set the value of rec_per_key when all fields
+      are bound (rec_per_key[2] in the example above).
+
+      If the handler doesn't support statistics, it should set all of the
+      above to 0.
+
+      We first scans through all partitions to get the one holding most rows.
+      We will then allow the handler with the most rows to set
+      the rec_per_key and use this as an estimate on the total table.
+
+      max_data_file_length:     Maximum data file length
+      We ignore it, is only used in
+      SHOW TABLE STATUS
+      max_index_file_length:    Maximum index file length
+      We ignore it since it is never used
+      block_size:               Block size used
+      We set it to the value of the first handler
+      ref_length:               We set this to the value calculated
+      and stored in local object
+      create_time:              Creation time of table
+
+      So we calculate these constants by using the variables from the
+      handler with most rows.
+    */
+    handler *file, **file_array;
+    ulonglong max_records= 0;
+    uint32 i= 0;
+    uint32 handler_instance= 0;
+    bool handler_instance_set= 0;
+
+    file_array= m_file;
+    do
+    {
+      file= *file_array;
+      if (bitmap_is_set(&(m_opened_partitions), (uint)(file_array - m_file)))
+      {
+        /* Get variables if not already done */
+        if (!(flag & HA_STATUS_VARIABLE) ||
+            !bitmap_is_set(&(m_part_info->read_partitions),
+                           (uint) (file_array - m_file)))
+          file->info(HA_STATUS_VARIABLE | no_lock_flag | extra_var_flag);
+        if (file->stats.records > max_records || !handler_instance_set)
+        {
+          handler_instance_set= 1;
+          max_records= file->stats.records;
+          handler_instance= i;
+        }
+      }
+      i++;
+    } while (*(++file_array));
+    /*
+      Sort the array of part_ids by number of records in
+      in descending order.
+    */
+    my_qsort2((void*) m_part_ids_sorted_by_num_of_records,
+              m_tot_parts,
+              sizeof(uint32),
+              (qsort2_cmp) compare_number_of_records,
+              this);
+
+    file= m_file[handler_instance];
+    file->info(HA_STATUS_CONST | no_lock_flag);
+    stats.block_size= file->stats.block_size;
+    stats.create_time= file->stats.create_time;
+    ref_length= m_ref_length;
+  }
+  if (flag & HA_STATUS_ERRKEY)
+  {
+    handler *file= m_file[m_last_part];
+    DBUG_PRINT("info", ("info: HA_STATUS_ERRKEY"));
+    /*
+      This flag is used to get index number of the unique index that
+      reported duplicate key
+      We will report the errkey on the last handler used and ignore the rest
+      Note: all engines does not support HA_STATUS_ERRKEY, so set errkey.
+    */
+    file->errkey= errkey;
+    file->info(HA_STATUS_ERRKEY | no_lock_flag);
+    errkey= file->errkey;
+  }
+  if (flag & HA_STATUS_TIME)
+  {
+    handler *file, **file_array;
+    DBUG_PRINT("info", ("info: HA_STATUS_TIME"));
+    /*
+      This flag is used to set the latest update time of the table.
+      Used by SHOW commands
+      We will report the maximum of these times
+    */
+    stats.update_time= 0;
+    file_array= m_file;
+    do
+    {
+      file= *file_array;
+      file->info(HA_STATUS_TIME | no_lock_flag);
+      if (file->stats.update_time > stats.update_time)
+	stats.update_time= file->stats.update_time;
+    } while (*(++file_array));
+  }
+  DBUG_RETURN(0);
+}
+
+
+void ha_partition::get_dynamic_partition_info(PARTITION_STATS *stat_info,
+                                              uint part_id)
+{
+  handler *file= m_file[part_id];
+  DBUG_ASSERT(bitmap_is_set(&(m_part_info->read_partitions), part_id));
+  file->info(HA_STATUS_TIME | HA_STATUS_VARIABLE |
+             HA_STATUS_VARIABLE_EXTRA | HA_STATUS_NO_LOCK);
+
+  stat_info->records=              file->stats.records;
+  stat_info->mean_rec_length=      file->stats.mean_rec_length;
+  stat_info->data_file_length=     file->stats.data_file_length;
+  stat_info->max_data_file_length= file->stats.max_data_file_length;
+  stat_info->index_file_length=    file->stats.index_file_length;
+  stat_info->max_index_file_length= file->stats.max_index_file_length;
+  stat_info->delete_length=        file->stats.delete_length;
+  stat_info->create_time=          file->stats.create_time;
+  stat_info->update_time=          file->stats.update_time;
+  stat_info->check_time=           file->stats.check_time;
+  stat_info->check_sum=            file->stats.checksum;
+  stat_info->check_sum_null=       file->stats.checksum_null;
+}
+
+
+void ha_partition::set_partitions_to_open(List<String> *partition_names)
+{
+  m_partitions_to_open= partition_names;
+}
+
+
+int ha_partition::open_read_partitions(char *name_buff, size_t name_buff_size)
+{
+  handler **file;
+  char *name_buffer_ptr;
+  int error= 0;
+
+  name_buffer_ptr= m_name_buffer_ptr;
+  file= m_file;
+  m_file_sample= NULL;
+  do
+  {
+    int n_file= (int)(file-m_file);
+    int is_open= bitmap_is_set(&m_opened_partitions, n_file);
+    int should_be_open= bitmap_is_set(&m_part_info->read_partitions, n_file);
+
+    /*
+      TODO: we can close some opened partitions if they're not
+      used in the query. It probably should be syncronized with the
+      table_open_cache value.
+
+      if (is_open && !should_be_open)
+      {
+        if (unlikely((error= (*file)->ha_close())))
+          goto err_handler;
+        bitmap_clear_bit(&m_opened_partitions, n_file);
+      }
+      else
+    */
+    if (!is_open && should_be_open)
+    {
+      LEX_CSTRING save_connect_string= table->s->connect_string;
+      if (unlikely((error=
+                    create_partition_name(name_buff, name_buff_size,
+                                          table->s->normalized_path.str,
+                                          name_buffer_ptr, NORMAL_PART_NAME,
+                                          FALSE))))
+        goto err_handler;
+      if (!((*file)->ht->flags & HTON_CAN_READ_CONNECT_STRING_IN_PARTITION))
+        table->s->connect_string= m_connect_string[(uint)(file-m_file)];
+      error= (*file)->ha_open(table, name_buff, m_mode,
+                              m_open_test_lock | HA_OPEN_NO_PSI_CALL);
+      table->s->connect_string= save_connect_string;
+      if (error)
+        goto err_handler;
+      bitmap_set_bit(&m_opened_partitions, n_file);
+      m_last_part= n_file;
+    }
+    if (!m_file_sample && should_be_open)
+      m_file_sample= *file;
+    name_buffer_ptr+= strlen(name_buffer_ptr) + 1;
+  } while (*(++file));
+  
+err_handler:
+  return error;
+}
+
+
+int ha_partition::change_partitions_to_open(List<String> *partition_names)
+{
+  char name_buff[FN_REFLEN+1];
+  int error= 0;
+
+  if (m_is_clone_of)
+    return 0;
+
+  m_partitions_to_open= partition_names;
+  if (unlikely((error= m_part_info->set_partition_bitmaps(partition_names))))
+    goto err_handler;
+
+  if (m_lock_type != F_UNLCK)
+  {
+    /*
+      That happens after the LOCK TABLE statement.
+      Do nothing in this case.
+    */
+    return 0;
+  }
+
+  check_insert_autoincrement();
+  if (bitmap_cmp(&m_opened_partitions, &m_part_info->read_partitions) != 0)
+    return 0;
+
+  if (unlikely((error= read_par_file(table->s->normalized_path.str)) ||
+               (error= open_read_partitions(name_buff, sizeof(name_buff)))))
+    goto err_handler;
+
+  clear_handler_file();
+
+err_handler:
+  return error;
+}
+
+
+static int extra_cb(handler *h, void *operation)
+{
+  return h->extra(*(enum ha_extra_function*)operation);
+}
+
+
+static int start_keyread_cb(handler* h, void *p)
+{
+  return h->ha_start_keyread(*(uint*)p);
+}
+
+
+static int end_keyread_cb(handler* h, void *unused)
+{
+  return h->ha_end_keyread();
+}
+
+
+/**
+  General function to prepare handler for certain behavior.
+
+  @param[in]    operation       operation to execute
+
+  @return       status
+    @retval     0               success
+    @retval     >0              error code
+
+  @detail
+
+  extra() is called whenever the server wishes to send a hint to
+  the storage engine. The MyISAM engine implements the most hints.
+
+  We divide the parameters into the following categories:
+  1) Operations used by most handlers
+  2) Operations used by some non-MyISAM handlers
+  3) Operations used only by MyISAM
+  4) Operations only used by temporary tables for query processing
+  5) Operations only used by MyISAM internally
+  6) Operations not used at all
+  7) Operations only used by federated tables for query processing
+  8) Operations only used by NDB
+  9) Operations only used by MERGE
+
+  The partition handler need to handle category 1), 2) and 3).
+
+  1) Operations used by most handlers
+  -----------------------------------
+  HA_EXTRA_RESET:
+    This option is used by most handlers and it resets the handler state
+    to the same state as after an open call. This includes releasing
+    any READ CACHE or WRITE CACHE or other internal buffer used.
+
+    It is called from the reset method in the handler interface. There are
+    three instances where this is called.
+    1) After completing a INSERT ... SELECT ... query the handler for the
+       table inserted into is reset
+    2) It is called from close_thread_table which in turn is called from
+       close_thread_tables except in the case where the tables are locked
+       in which case ha_commit_stmt is called instead.
+       It is only called from here if refresh_version hasn't changed and the
+       table is not an old table when calling close_thread_table.
+       close_thread_tables is called from many places as a general clean up
+       function after completing a query.
+    3) It is called when deleting the QUICK_RANGE_SELECT object if the
+       QUICK_RANGE_SELECT object had its own handler object. It is called
+       immediately before close of this local handler object.
+  HA_EXTRA_KEYREAD:
+  HA_EXTRA_NO_KEYREAD:
+    These parameters are used to provide an optimisation hint to the handler.
+    If HA_EXTRA_KEYREAD is set it is enough to read the index fields, for
+    many handlers this means that the index-only scans can be used and it
+    is not necessary to use the real records to satisfy this part of the
+    query. Index-only scans is a very important optimisation for disk-based
+    indexes. For main-memory indexes most indexes contain a reference to the
+    record and thus KEYREAD only says that it is enough to read key fields.
+    HA_EXTRA_NO_KEYREAD disables this for the handler, also HA_EXTRA_RESET
+    will disable this option.
+    The handler will set HA_KEYREAD_ONLY in its table flags to indicate this
+    feature is supported.
+  HA_EXTRA_FLUSH:
+    Indication to flush tables to disk, is supposed to be used to
+    ensure disk based tables are flushed at end of query execution.
+    Currently is never used.
+
+  HA_EXTRA_FORCE_REOPEN:
+    Only used by MyISAM and Archive, called when altering table,
+    closing tables to enforce a reopen of the table files.
+
+  2) Operations used by some non-MyISAM handlers
+  ----------------------------------------------
+  HA_EXTRA_KEYREAD_PRESERVE_FIELDS:
+    This is a strictly InnoDB feature that is more or less undocumented.
+    When it is activated InnoDB copies field by field from its fetch
+    cache instead of all fields in one memcpy. Have no idea what the
+    purpose of this is.
+    Cut from include/my_base.h:
+    When using HA_EXTRA_KEYREAD, overwrite only key member fields and keep
+    other fields intact. When this is off (by default) InnoDB will use memcpy
+    to overwrite entire row.
+  HA_EXTRA_IGNORE_DUP_KEY:
+  HA_EXTRA_NO_IGNORE_DUP_KEY:
+    Informs the handler to we will not stop the transaction if we get an
+    duplicate key errors during insert/update.
+    Always called in pair, triggered by INSERT IGNORE and other similar
+    SQL constructs.
+    Not used by MyISAM.
+
+  3) Operations used only by MyISAM
+  ---------------------------------
+  HA_EXTRA_NORMAL:
+    Only used in MyISAM to reset quick mode, not implemented by any other
+    handler. Quick mode is also reset in MyISAM by HA_EXTRA_RESET.
+
+    It is called after completing a successful DELETE query if the QUICK
+    option is set.
+
+  HA_EXTRA_QUICK:
+    When the user does DELETE QUICK FROM table where-clause; this extra
+    option is called before the delete query is performed and
+    HA_EXTRA_NORMAL is called after the delete query is completed.
+    Temporary tables used internally in MySQL always set this option
+
+    The meaning of quick mode is that when deleting in a B-tree no merging
+    of leafs is performed. This is a common method and many large DBMS's
+    actually only support this quick mode since it is very difficult to
+    merge leaves in a tree used by many threads concurrently.
+
+  HA_EXTRA_CACHE:
+    This flag is usually set with extra_opt along with a cache size.
+    The size of this buffer is set by the user variable
+    record_buffer_size. The value of this cache size is the amount of
+    data read from disk in each fetch when performing a table scan.
+    This means that before scanning a table it is normal to call
+    extra with HA_EXTRA_CACHE and when the scan is completed to call
+    HA_EXTRA_NO_CACHE to release the cache memory.
+
+    Some special care is taken when using this extra parameter since there
+    could be a write ongoing on the table in the same statement. In this
+    one has to take special care since there might be a WRITE CACHE as
+    well. HA_EXTRA_CACHE specifies using a READ CACHE and using
+    READ CACHE and WRITE CACHE at the same time is not possible.
+
+    Only MyISAM currently use this option.
+
+    It is set when doing full table scans using rr_sequential and
+    reset when completing such a scan with end_read_record
+    (resetting means calling extra with HA_EXTRA_NO_CACHE).
+
+    It is set in filesort.cc for MyISAM internal tables and it is set in
+    a multi-update where HA_EXTRA_CACHE is called on a temporary result
+    table and after that ha_rnd_init(0) on table to be updated
+    and immediately after that HA_EXTRA_NO_CACHE on table to be updated.
+
+    Apart from that it is always used from init_read_record but not when
+    used from UPDATE statements. It is not used from DELETE statements
+    with ORDER BY and LIMIT but it is used in normal scan loop in DELETE
+    statements. The reason here is that DELETE's in MyISAM doesn't move
+    existings data rows.
+
+    It is also set in copy_data_between_tables when scanning the old table
+    to copy over to the new table.
+    And it is set in join_init_read_record where quick objects are used
+    to perform a scan on the table. In this case the full table scan can
+    even be performed multiple times as part of the nested loop join.
+
+    For purposes of the partition handler it is obviously necessary to have
+    special treatment of this extra call. If we would simply pass this
+    extra call down to each handler we would allocate
+    cache size * no of partitions amount of memory and this is not
+    necessary since we will only scan one partition at a time when doing
+    full table scans.
+
+    Thus we treat it by first checking whether we have MyISAM handlers in
+    the table, if not we simply ignore the call and if we have we will
+    record the call but will not call any underlying handler yet. Then
+    when performing the sequential scan we will check this recorded value
+    and call extra_opt whenever we start scanning a new partition.
+
+  HA_EXTRA_NO_CACHE:
+    When performing a UNION SELECT HA_EXTRA_NO_CACHE is called from the
+    flush method in the select_union class.
+    It is used to some extent when insert delayed inserts.
+    See HA_EXTRA_RESET_STATE for use in conjunction with delete_all_rows().
+
+    It should be ok to call HA_EXTRA_NO_CACHE on all underlying handlers
+    if they are MyISAM handlers. Other handlers we can ignore the call
+    for. If no cache is in use they will quickly return after finding
+    this out. And we also ensure that all caches are disabled and no one
+    is left by mistake.
+    In the future this call will probably be deleted and we will instead call
+    ::reset();
+
+  HA_EXTRA_WRITE_CACHE:
+    See above, called from various places. It is mostly used when we
+    do INSERT ... SELECT
+    No special handling to save cache space is developed currently.
+
+  HA_EXTRA_PREPARE_FOR_UPDATE:
+    This is called as part of a multi-table update. When the table to be
+    updated is also scanned then this informs MyISAM handler to drop any
+    caches if dynamic records are used (fixed size records do not care
+    about this call). We pass this along to the first partition to scan, and
+    flag that it is to be called after HA_EXTRA_CACHE when moving to the next
+    partition to scan.
+
+  HA_EXTRA_PREPARE_FOR_DROP:
+    Only used by MyISAM, called in preparation for a DROP TABLE.
+    It's used mostly by Windows that cannot handle dropping an open file.
+    On other platforms it has the same effect as HA_EXTRA_FORCE_REOPEN.
+
+  HA_EXTRA_PREPARE_FOR_RENAME:
+    Informs the handler we are about to attempt a rename of the table.
+    For handlers that have share open files (MyISAM key-file and
+    Archive writer) they must close the files before rename is possible
+    on Windows.
+
+  HA_EXTRA_READCHECK:
+  HA_EXTRA_NO_READCHECK:
+    Only one call to HA_EXTRA_NO_READCHECK from ha_open where it says that
+    this is not needed in SQL. The reason for this call is that MyISAM sets
+    the READ_CHECK_USED in the open call so the call is needed for MyISAM
+    to reset this feature.
+    The idea with this parameter was to inform of doing/not doing a read
+    check before applying an update. Since SQL always performs a read before
+    applying the update No Read Check is needed in MyISAM as well.
+
+    This is a cut from Docs/myisam.txt
+     Sometimes you might want to force an update without checking whether
+     another user has changed the record since you last read it. This is
+     somewhat dangerous, so it should ideally not be used. That can be
+     accomplished by wrapping the mi_update() call in two calls to mi_extra(),
+     using these functions:
+     HA_EXTRA_NO_READCHECK=5                 No readcheck on update
+     HA_EXTRA_READCHECK=6                    Use readcheck (def)
+
+  HA_EXTRA_REMEMBER_POS:
+  HA_EXTRA_RESTORE_POS:
+    System versioning needs this for MyISAM and Aria tables.
+    On DELETE using PRIMARY KEY:
+    1) handler::ha_index_read_map() saves rowid used for row delete/update
+    2) handler::ha_update_row() can rewrite saved rowid
+    3) handler::ha_delete_row()/handler::ha_update_row() expects saved but got
+       different rowid and operation fails
+    Using those flags prevents harmful side effect of 2)
+
+  4) Operations only used by temporary tables for query processing
+  ----------------------------------------------------------------
+  HA_EXTRA_RESET_STATE:
+    Same as reset() except that buffers are not released. If there is
+    a READ CACHE it is reinit'ed. A cache is reinit'ed to restart reading
+    or to change type of cache between READ CACHE and WRITE CACHE.
+
+    This extra function is always called immediately before calling
+    delete_all_rows on the handler for temporary tables.
+    There are cases however when HA_EXTRA_RESET_STATE isn't called in
+    a similar case for a temporary table in sql_union.cc and in two other
+    cases HA_EXTRA_NO_CACHE is called before and HA_EXTRA_WRITE_CACHE
+    called afterwards.
+    The case with HA_EXTRA_NO_CACHE and HA_EXTRA_WRITE_CACHE means
+    disable caching, delete all rows and enable WRITE CACHE. This is
+    used for temporary tables containing distinct sums and a
+    functional group.
+
+    The only case that delete_all_rows is called on non-temporary tables
+    is in sql_delete.cc when DELETE FROM table; is called by a user.
+    In this case no special extra calls are performed before or after this
+    call.
+
+    The partition handler should not need to bother about this one. It
+    should never be called.
+
+  HA_EXTRA_NO_ROWS:
+    Don't insert rows indication to HEAP and MyISAM, only used by temporary
+    tables used in query processing.
+    Not handled by partition handler.
+
+  5) Operations only used by MyISAM internally
+  --------------------------------------------
+  HA_EXTRA_REINIT_CACHE:
+    This call reinitializes the READ CACHE described above if there is one
+    and otherwise the call is ignored.
+
+    We can thus safely call it on all underlying handlers if they are
+    MyISAM handlers. It is however never called so we don't handle it at all.
+  HA_EXTRA_FLUSH_CACHE:
+    Flush WRITE CACHE in MyISAM. It is only from one place in the code.
+    This is in sql_insert.cc where it is called if the table_flags doesn't
+    contain HA_DUPLICATE_POS. The only handler having the HA_DUPLICATE_POS
+    set is the MyISAM handler and so the only handler not receiving this
+    call is MyISAM.
+    Thus in effect this call is called but never used. Could be removed
+    from sql_insert.cc
+  HA_EXTRA_NO_USER_CHANGE:
+    Only used by MyISAM, never called.
+    Simulates lock_type as locked.
+  HA_EXTRA_WAIT_LOCK:
+  HA_EXTRA_WAIT_NOLOCK:
+    Only used by MyISAM, called from MyISAM handler but never from server
+    code on top of the handler.
+    Sets lock_wait on/off
+  HA_EXTRA_NO_KEYS:
+    Only used MyISAM, only used internally in MyISAM handler, never called
+    from server level.
+  HA_EXTRA_KEYREAD_CHANGE_POS:
+  HA_EXTRA_PRELOAD_BUFFER_SIZE:
+  HA_EXTRA_CHANGE_KEY_TO_DUP:
+  HA_EXTRA_CHANGE_KEY_TO_UNIQUE:
+    Only used by MyISAM, never called.
+
+  6) Operations not used at all
+  -----------------------------
+  HA_EXTRA_KEY_CACHE:
+  HA_EXTRA_NO_KEY_CACHE:
+    This parameters are no longer used and could be removed.
+
+  7) Operations only used by federated tables for query processing
+  ----------------------------------------------------------------
+  HA_EXTRA_INSERT_WITH_UPDATE:
+    Inform handler that an "INSERT...ON DUPLICATE KEY UPDATE" will be
+    executed. This condition is unset by HA_EXTRA_NO_IGNORE_DUP_KEY.
+
+  8) Operations only used by NDB
+  ------------------------------
+  HA_EXTRA_DELETE_CANNOT_BATCH:
+  HA_EXTRA_UPDATE_CANNOT_BATCH:
+    Inform handler that delete_row()/update_row() cannot batch deletes/updates
+    and should perform them immediately. This may be needed when table has
+    AFTER DELETE/UPDATE triggers which access to subject table.
+    These flags are reset by the handler::extra(HA_EXTRA_RESET) call.
+
+  9) Operations only used by MERGE
+  ------------------------------
+  HA_EXTRA_ADD_CHILDREN_LIST:
+  HA_EXTRA_ATTACH_CHILDREN:
+  HA_EXTRA_IS_ATTACHED_CHILDREN:
+  HA_EXTRA_DETACH_CHILDREN:
+    Special actions for MERGE tables. Ignore.
+*/
+
+int ha_partition::extra(enum ha_extra_function operation)
+{
+  DBUG_ENTER("ha_partition:extra");
+  DBUG_PRINT("enter", ("operation: %d", (int) operation));
+
+  switch (operation) {
+    /* Category 1), used by most handlers */
+  case HA_EXTRA_NO_KEYREAD:
+    DBUG_RETURN(loop_partitions(end_keyread_cb, NULL));
+  case HA_EXTRA_KEYREAD:
+  case HA_EXTRA_FLUSH:
+  case HA_EXTRA_PREPARE_FOR_FORCED_CLOSE:
+    DBUG_RETURN(loop_partitions(extra_cb, &operation));
+  case HA_EXTRA_PREPARE_FOR_RENAME:
+  case HA_EXTRA_FORCE_REOPEN:
+    DBUG_RETURN(loop_extra_alter(operation));
+    break;
+
+    /* Category 2), used by non-MyISAM handlers */
+  case HA_EXTRA_IGNORE_DUP_KEY:
+  case HA_EXTRA_NO_IGNORE_DUP_KEY:
+  case HA_EXTRA_KEYREAD_PRESERVE_FIELDS:
+  {
+    if (!m_myisam)
+      DBUG_RETURN(loop_partitions(extra_cb, &operation));
+  }
+  break;
+
+  /* Category 3), used by MyISAM handlers */
+  case HA_EXTRA_PREPARE_FOR_UPDATE:
+    /*
+      Needs to be run on the first partition in the range now, and
+      later in late_extra_cache, when switching to a new partition to scan.
+    */
+    m_extra_prepare_for_update= TRUE;
+    if (m_part_spec.start_part != NO_CURRENT_PART_ID)
+    {
+      if (!m_extra_cache)
+        m_extra_cache_part_id= m_part_spec.start_part;
+      DBUG_ASSERT(m_extra_cache_part_id == m_part_spec.start_part);
+      (void) m_file[m_part_spec.start_part]->extra(HA_EXTRA_PREPARE_FOR_UPDATE);
+    }
+    break;
+  case HA_EXTRA_NORMAL:
+  case HA_EXTRA_QUICK:
+  case HA_EXTRA_PREPARE_FOR_DROP:
+  case HA_EXTRA_FLUSH_CACHE:
+  case HA_EXTRA_PREPARE_FOR_ALTER_TABLE:
+  case HA_EXTRA_REMEMBER_POS:
+  case HA_EXTRA_RESTORE_POS:
+  {
+    DBUG_RETURN(loop_partitions(extra_cb, &operation));
+  }
+  case HA_EXTRA_NO_READCHECK:
+  {
+    /*
+      This is only done as a part of ha_open, which is also used in
+      ha_partition::open, so no need to do anything.
+    */
+    break;
+  }
+  case HA_EXTRA_CACHE:
+  {
+    prepare_extra_cache(0);
+    break;
+  }
+  case HA_EXTRA_NO_CACHE:
+  {
+    int ret= 0;
+    if (m_extra_cache_part_id != NO_CURRENT_PART_ID)
+      ret= m_file[m_extra_cache_part_id]->extra(HA_EXTRA_NO_CACHE);
+    m_extra_cache= FALSE;
+    m_extra_cache_size= 0;
+    m_extra_prepare_for_update= FALSE;
+    m_extra_cache_part_id= NO_CURRENT_PART_ID;
+    DBUG_RETURN(ret);
+  }
+  case HA_EXTRA_WRITE_CACHE:
+  {
+    m_extra_cache= FALSE;
+    m_extra_cache_size= 0;
+    m_extra_prepare_for_update= FALSE;
+    m_extra_cache_part_id= NO_CURRENT_PART_ID;
+    DBUG_RETURN(loop_partitions(extra_cb, &operation));
+  }
+  case HA_EXTRA_IGNORE_NO_KEY:
+  case HA_EXTRA_NO_IGNORE_NO_KEY:
+  {
+    /*
+      Ignore as these are specific to NDB for handling
+      idempotency
+     */
+    break;
+  }
+  case HA_EXTRA_WRITE_CAN_REPLACE:
+  case HA_EXTRA_WRITE_CANNOT_REPLACE:
+  {
+    /*
+      Informs handler that write_row() can replace rows which conflict
+      with row being inserted by PK/unique key without reporting error
+      to the SQL-layer.
+
+      At this time, this is safe by limitation of ha_partition
+    */
+    DBUG_RETURN(loop_partitions(extra_cb, &operation));
+  }
+    /* Category 7), used by federated handlers */
+  case HA_EXTRA_INSERT_WITH_UPDATE:
+    DBUG_RETURN(loop_partitions(extra_cb, &operation));
+    /* Category 8) Operations only used by NDB */
+  case HA_EXTRA_DELETE_CANNOT_BATCH:
+  case HA_EXTRA_UPDATE_CANNOT_BATCH:
+  {
+    /* Currently only NDB use the *_CANNOT_BATCH */
+    break;
+  }
+    /* Category 9) Operations only used by MERGE */
+  case HA_EXTRA_ADD_CHILDREN_LIST:
+    DBUG_RETURN(loop_partitions(extra_cb, &operation));
+  case HA_EXTRA_ATTACH_CHILDREN:
+  {
+    int result;
+    uint num_locks;
+    handler **file;
+    if ((result= loop_partitions(extra_cb, &operation)))
+      DBUG_RETURN(result);
+
+    /* Recalculate lock count as each child may have different set of locks */
+    num_locks= 0;
+    file= m_file;
+    do
+    {
+      num_locks+= (*file)->lock_count();
+    } while (*(++file));
+
+    m_num_locks= num_locks;
+    break;
+  }
+  case HA_EXTRA_IS_ATTACHED_CHILDREN:
+    DBUG_RETURN(loop_partitions(extra_cb, &operation));
+  case HA_EXTRA_DETACH_CHILDREN:
+    DBUG_RETURN(loop_partitions(extra_cb, &operation));
+  case HA_EXTRA_MARK_AS_LOG_TABLE:
+  /*
+    http://dev.mysql.com/doc/refman/5.1/en/partitioning-limitations.html
+    says we no longer support logging to partitioned tables, so we fail
+    here.
+  */
+    DBUG_RETURN(ER_UNSUPORTED_LOG_ENGINE);
+  case HA_EXTRA_STARTING_ORDERED_INDEX_SCAN:
+  case HA_EXTRA_BEGIN_ALTER_COPY:
+  case HA_EXTRA_END_ALTER_COPY:
+    DBUG_RETURN(loop_partitions(extra_cb, &operation));
+  default:
+  {
+    /* Temporary crash to discover what is wrong */
+    DBUG_ASSERT(0);
+    break;
+  }
+  }
+  DBUG_RETURN(1);
+}
+
+
+/**
+  Special extra call to reset extra parameters
+
+  @return Operation status.
+    @retval >0 Error code
+    @retval 0  Success
+
+  @note Called at end of each statement to reset buffers.
+  To avoid excessive calls, the m_partitions_to_reset bitmap keep records
+  of which partitions that have been used in extra(), external_lock() or
+  start_stmt() and is needed to be called.
+*/
+
+int ha_partition::reset(void)
+{
+  int result= 0;
+  int tmp;
+  uint i;
+  DBUG_ENTER("ha_partition::reset");
+
+  for (i= bitmap_get_first_set(&m_partitions_to_reset);
+       i < m_tot_parts;
+       i= bitmap_get_next_set(&m_partitions_to_reset, i))
+  {
+    if (bitmap_is_set(&m_opened_partitions, i) &&
+        (tmp= m_file[i]->ha_reset()))
+      result= tmp;
+  }
+  bitmap_clear_all(&m_partitions_to_reset);
+  m_extra_prepare_for_update= FALSE;
+  DBUG_RETURN(result);
+}
+
+/**
+  Special extra method with additional parameter
+  See @ref ha_partition::extra
+
+  @param[in]    operation       operation to execute
+  @param[in]    arg             extra argument
+
+  @return       status
+    @retval     0               success
+    @retval     >0              error code
+
+  @detail
+    Operations supported by extra_opt:
+    HA_EXTRA_KEYREAD:
+      arg is interpreted as key index
+    HA_EXTRA_CACHE:
+      arg is interpreted as size of cache in full table scan
+
+    For detailed description refer to @ref ha_partition::extra
+*/
+
+int ha_partition::extra_opt(enum ha_extra_function operation, ulong arg)
+{
+  DBUG_ENTER("ha_partition::extra_opt");
+
+  switch (operation)
+  {
+    case HA_EXTRA_KEYREAD:
+      DBUG_RETURN(loop_partitions(start_keyread_cb, &arg));
+    case HA_EXTRA_CACHE:
+      prepare_extra_cache(arg);
+      DBUG_RETURN(0);
+    default:
+      DBUG_ASSERT(0);
+  }
+  DBUG_RETURN(1);
+}
+
+
+/*
+  Call extra on handler with HA_EXTRA_CACHE and cachesize
+
+  SYNOPSIS
+    prepare_extra_cache()
+    cachesize                Size of cache for full table scan
+
+  RETURN VALUE
+    NONE
+*/
+
+void ha_partition::prepare_extra_cache(uint cachesize)
+{
+  DBUG_ENTER("ha_partition::prepare_extra_cache");
+  DBUG_PRINT("enter", ("cachesize %u", cachesize));
+
+  m_extra_cache= TRUE;
+  m_extra_cache_size= cachesize;
+  if (m_part_spec.start_part != NO_CURRENT_PART_ID)
+  {
+    DBUG_ASSERT(bitmap_is_set(&m_partitions_to_reset,
+                              m_part_spec.start_part));
+    bitmap_set_bit(&m_partitions_to_reset, m_part_spec.start_part);
+    late_extra_cache(m_part_spec.start_part);
+  }
+  DBUG_VOID_RETURN;
+}
+
+
+/**
+  Prepares our new and reorged handlers for rename or delete.
+
+  @param operation Operation to forward
+
+  @return Operation status
+    @retval 0  Success
+    @retval !0 Error
+*/
+
+int ha_partition::loop_extra_alter(enum ha_extra_function operation)
+{
+  int result= 0, tmp;
+  handler **file;
+  DBUG_ENTER("ha_partition::loop_extra_alter");
+  DBUG_ASSERT(operation == HA_EXTRA_PREPARE_FOR_RENAME ||
+              operation == HA_EXTRA_FORCE_REOPEN);
+
+  if (m_new_file != NULL)
+  {
+    for (file= m_new_file; *file; file++)
+      if ((tmp= (*file)->extra(operation)))
+        result= tmp;
+  }
+  if (m_reorged_file != NULL)
+  {
+    for (file= m_reorged_file; *file; file++)
+      if ((tmp= (*file)->extra(operation)))
+        result= tmp;
+  }
+  if ((tmp= loop_partitions(extra_cb, &operation)))
+    result= tmp;
+  DBUG_RETURN(result);
+}
+
+
+/**
+  Call callback(part, param) on all partitions
+
+    @param callback                 a callback to call for each partition
+    @param param                    a void*-parameter passed to callback
+
+    @return Operation status
+      @retval >0                    Error code
+      @retval 0                     Success
+*/
+
+int ha_partition::loop_partitions(handler_callback callback, void *param)
+{
+  int result= 0, tmp;
+  uint i;
+  DBUG_ENTER("ha_partition::loop_partitions");
+
+  for (i= bitmap_get_first_set(&m_part_info->lock_partitions);
+       i < m_tot_parts;
+       i= bitmap_get_next_set(&m_part_info->lock_partitions, i))
+  {
+    /*
+      This can be called after an error in ha_open.
+      In this case calling 'extra' can crash.
+    */
+    if (bitmap_is_set(&m_opened_partitions, i) &&
+        (tmp= callback(m_file[i], param)))
+      result= tmp;
+  }
+  /* Add all used partitions to be called in reset(). */
+  bitmap_union(&m_partitions_to_reset, &m_part_info->lock_partitions);
+  DBUG_RETURN(result);
+}
+
+
+/*
+  Call extra(HA_EXTRA_CACHE) on next partition_id
+
+  SYNOPSIS
+    late_extra_cache()
+    partition_id               Partition id to call extra on
+
+  RETURN VALUE
+    NONE
+*/
+
+void ha_partition::late_extra_cache(uint partition_id)
+{
+  handler *file;
+  DBUG_ENTER("ha_partition::late_extra_cache");
+  DBUG_PRINT("enter", ("extra_cache %u prepare %u partid %u size %u",
+                       m_extra_cache, m_extra_prepare_for_update,
+                       partition_id, m_extra_cache_size));
+
+  if (!m_extra_cache && !m_extra_prepare_for_update)
+    DBUG_VOID_RETURN;
+  file= m_file[partition_id];
+  if (m_extra_cache)
+  {
+    if (m_extra_cache_size == 0)
+      (void) file->extra(HA_EXTRA_CACHE);
+    else
+      (void) file->extra_opt(HA_EXTRA_CACHE, m_extra_cache_size);
+  }
+  if (m_extra_prepare_for_update)
+  {
+    (void) file->extra(HA_EXTRA_PREPARE_FOR_UPDATE);
+  }
+  m_extra_cache_part_id= partition_id;
+  DBUG_VOID_RETURN;
+}
+
+
+/*
+  Call extra(HA_EXTRA_NO_CACHE) on next partition_id
+
+  SYNOPSIS
+    late_extra_no_cache()
+    partition_id               Partition id to call extra on
+
+  RETURN VALUE
+    NONE
+*/
+
+void ha_partition::late_extra_no_cache(uint partition_id)
+{
+  handler *file;
+  DBUG_ENTER("ha_partition::late_extra_no_cache");
+
+  if (!m_extra_cache && !m_extra_prepare_for_update)
+    DBUG_VOID_RETURN;
+  file= m_file[partition_id];
+  (void) file->extra(HA_EXTRA_NO_CACHE);
+  DBUG_ASSERT(partition_id == m_extra_cache_part_id);
+  m_extra_cache_part_id= NO_CURRENT_PART_ID;
+  DBUG_VOID_RETURN;
+}
+
+
+/****************************************************************************
+                MODULE optimiser support
+****************************************************************************/
+
+/**
+  Get keys to use for scanning.
+
+  @return key_map of keys usable for scanning
+
+  @note No need to use read_partitions here, since it does not depend on
+  which partitions is used, only which storage engine used.
+*/
+
+const key_map *ha_partition::keys_to_use_for_scanning()
+{
+  DBUG_ENTER("ha_partition::keys_to_use_for_scanning");
+  DBUG_RETURN(get_open_file_sample()->keys_to_use_for_scanning());
+}
+
+
+/**
+  Minimum number of rows to base optimizer estimate on.
+*/
+
+ha_rows ha_partition::min_rows_for_estimate()
+{
+  uint i, max_used_partitions, tot_used_partitions;
+  DBUG_ENTER("ha_partition::min_rows_for_estimate");
+
+  tot_used_partitions= bitmap_bits_set(&m_part_info->read_partitions);
+
+  /*
+    All partitions might have been left as unused during partition pruning
+    due to, for example, an impossible WHERE condition. Nonetheless, the
+    optimizer might still attempt to perform (e.g. range) analysis where an
+    estimate of the the number of rows is calculated using records_in_range.
+    Hence, to handle this and other possible cases, use zero as the minimum
+    number of rows to base the estimate on if no partition is being used.
+  */
+  if (!tot_used_partitions)
+    DBUG_RETURN(0);
+
+  /*
+    Allow O(log2(tot_partitions)) increase in number of used partitions.
+    This gives O(tot_rows/log2(tot_partitions)) rows to base the estimate on.
+    I.e when the total number of partitions doubles, allow one more
+    partition to be checked.
+  */
+  i= 2;
+  max_used_partitions= 1;
+  while (i < m_tot_parts)
+  {
+    max_used_partitions++;
+    i= i << 1;
+  }
+  if (max_used_partitions > tot_used_partitions)
+    max_used_partitions= tot_used_partitions;
+
+  /* stats.records is already updated by the info(HA_STATUS_VARIABLE) call. */
+  DBUG_PRINT("info", ("max_used_partitions: %u tot_rows: %lu",
+                      max_used_partitions,
+                      (ulong) stats.records));
+  DBUG_PRINT("info", ("tot_used_partitions: %u min_rows_to_check: %lu",
+                      tot_used_partitions,
+                      (ulong) stats.records * max_used_partitions
+                              / tot_used_partitions));
+  DBUG_RETURN(stats.records * max_used_partitions / tot_used_partitions);
+}
+
+
+/**
+  Get the biggest used partition.
+
+  Starting at the N:th biggest partition and skips all non used
+  partitions, returning the biggest used partition found
+
+  @param[in,out] part_index  Skip the *part_index biggest partitions
+
+  @return The biggest used partition with index not lower than *part_index.
+    @retval NO_CURRENT_PART_ID     No more partition used.
+    @retval != NO_CURRENT_PART_ID  partition id of biggest used partition with
+                                   index >= *part_index supplied. Note that
+                                   *part_index will be updated to the next
+                                   partition index to use.
+*/
+
+uint ha_partition::get_biggest_used_partition(uint *part_index)
+{
+  uint part_id;
+  while ((*part_index) < m_tot_parts)
+  {
+    part_id= m_part_ids_sorted_by_num_of_records[(*part_index)++];
+    if (bitmap_is_set(&m_part_info->read_partitions, part_id))
+      return part_id;
+  }
+  return NO_CURRENT_PART_ID;
+}
+
+
+/*
+  Return time for a scan of the table
+
+  SYNOPSIS
+    scan_time()
+
+  RETURN VALUE
+    time for scan
+*/
+
+double ha_partition::scan_time()
+{
+  double scan_time= 0;
+  uint i;
+  DBUG_ENTER("ha_partition::scan_time");
+
+  for (i= bitmap_get_first_set(&m_part_info->read_partitions);
+       i < m_tot_parts;
+       i= bitmap_get_next_set(&m_part_info->read_partitions, i))
+    scan_time+= m_file[i]->scan_time();
+  DBUG_RETURN(scan_time);
+}
+
+
+/**
+  @brief
+  Caculate time to scan the given index (index only scan)
+
+  @param inx      Index number to scan
+
+  @return time for scanning index inx
+*/
+
+double ha_partition::key_scan_time(uint inx)
+{
+  double scan_time= 0;
+  uint i;
+  DBUG_ENTER("ha_partition::key_scan_time");
+  for (i= bitmap_get_first_set(&m_part_info->read_partitions);
+       i < m_tot_parts;
+       i= bitmap_get_next_set(&m_part_info->read_partitions, i))
+    scan_time+= m_file[i]->key_scan_time(inx);
+  DBUG_RETURN(scan_time);
+}
+
+
+double ha_partition::keyread_time(uint inx, uint ranges, ha_rows rows)
+{
+  double read_time= 0;
+  uint i;
+  DBUG_ENTER("ha_partition::keyread_time");
+  if (!ranges)
+    DBUG_RETURN(handler::keyread_time(inx, ranges, rows));
+  for (i= bitmap_get_first_set(&m_part_info->read_partitions);
+       i < m_tot_parts;
+       i= bitmap_get_next_set(&m_part_info->read_partitions, i))
+    read_time+= m_file[i]->keyread_time(inx, ranges, rows);
+  DBUG_RETURN(read_time);
+}
+
+
+/**
+  Find number of records in a range.
+  @param inx      Index number
+  @param min_key  Start of range
+  @param max_key  End of range
+
+  @return Number of rows in range.
+
+  Given a starting key, and an ending key estimate the number of rows that
+  will exist between the two. max_key may be empty which in case determine
+  if start_key matches any rows.
+*/
+
+ha_rows ha_partition::records_in_range(uint inx, const key_range *min_key,
+				       const key_range *max_key,
+                                       page_range *pages)
+{
+  ha_rows min_rows_to_check, rows, estimated_rows=0, checked_rows= 0;
+  uint partition_index= 0, part_id;
+  page_range ignore_pages;
+  DBUG_ENTER("ha_partition::records_in_range");
+
+  /* Don't calculate pages of more than one active partition */
+  if (bitmap_bits_set(&m_part_info->read_partitions) != 1)
+    pages= &ignore_pages;
+
+  min_rows_to_check= min_rows_for_estimate();
+
+  while ((part_id= get_biggest_used_partition(&partition_index))
+         != NO_CURRENT_PART_ID)
+  {
+    rows= m_file[part_id]->records_in_range(inx, min_key, max_key, pages);
+
+    DBUG_PRINT("info", ("part %u match %lu rows of %lu", part_id, (ulong) rows,
+                        (ulong) m_file[part_id]->stats.records));
+
+    if (rows == HA_POS_ERROR)
+      DBUG_RETURN(HA_POS_ERROR);
+    estimated_rows+= rows;
+    checked_rows+= m_file[part_id]->stats.records;
+    /*
+      Returning 0 means no rows can be found, so we must continue
+      this loop as long as we have estimated_rows == 0.
+      Also many engines return 1 to indicate that there may exist
+      a matching row, we do not normalize this by dividing by number of
+      used partitions, but leave it to be returned as a sum, which will
+      reflect that we will need to scan each partition's index.
+
+      Note that this statistics may not always be correct, so we must
+      continue even if the current partition has 0 rows, since we might have
+      deleted rows from the current partition, or inserted to the next
+      partition.
+    */
+    if (estimated_rows && checked_rows &&
+        checked_rows >= min_rows_to_check)
+    {
+      DBUG_PRINT("info",
+                 ("records_in_range(inx %u): %lu (%lu * %lu / %lu)",
+                  inx,
+                  (ulong) (estimated_rows * stats.records / checked_rows),
+                  (ulong) estimated_rows,
+                  (ulong) stats.records,
+                  (ulong) checked_rows));
+      DBUG_RETURN(estimated_rows * stats.records / checked_rows);
+    }
+  }
+  DBUG_PRINT("info", ("records_in_range(inx %u): %lu",
+                      inx,
+                      (ulong) estimated_rows));
+  DBUG_RETURN(estimated_rows);
+}
+
+
+/**
+  Estimate upper bound of number of rows.
+
+  @return Number of rows.
+*/
+
+ha_rows ha_partition::estimate_rows_upper_bound()
+{
+  ha_rows rows, tot_rows= 0;
+  handler **file= m_file;
+  DBUG_ENTER("ha_partition::estimate_rows_upper_bound");
+
+  do
+  {
+    if (bitmap_is_set(&(m_part_info->read_partitions), (uint)(file - m_file)))
+    {
+      rows= (*file)->estimate_rows_upper_bound();
+      if (rows == HA_POS_ERROR)
+        DBUG_RETURN(HA_POS_ERROR);
+      tot_rows+= rows;
+    }
+  } while (*(++file));
+  DBUG_RETURN(tot_rows);
+}
+
+
+/*
+  Get time to read
+
+  SYNOPSIS
+    read_time()
+    index                Index number used
+    ranges               Number of ranges
+    rows                 Number of rows
+
+  RETURN VALUE
+    time for read
+
+  DESCRIPTION
+    This will be optimised later to include whether or not the index can
+    be used with partitioning. To achieve we need to add another parameter
+    that specifies how many of the index fields that are bound in the ranges.
+    Possibly added as a new call to handlers.
+*/
+
+double ha_partition::read_time(uint index, uint ranges, ha_rows rows)
+{
+  DBUG_ENTER("ha_partition::read_time");
+
+  DBUG_RETURN(get_open_file_sample()->read_time(index, ranges, rows));
+}
+
+
+/**
+  Number of rows in table. see handler.h
+
+  @return Number of records in the table (after pruning!)
+*/
+
+ha_rows ha_partition::records()
+{
+  ha_rows tot_rows= 0;
+  uint i;
+  DBUG_ENTER("ha_partition::records");
+
+  for (i= bitmap_get_first_set(&m_part_info->read_partitions);
+       i < m_tot_parts;
+       i= bitmap_get_next_set(&m_part_info->read_partitions, i))
+  {
+    if (unlikely(m_file[i]->pre_records()))
+      DBUG_RETURN(HA_POS_ERROR);
+    const ha_rows rows= m_file[i]->records();
+    if (unlikely(rows == HA_POS_ERROR))
+      DBUG_RETURN(HA_POS_ERROR);
+    tot_rows+= rows;
+  }
+  DBUG_PRINT("exit", ("records: %lld", (longlong) tot_rows));
+  DBUG_RETURN(tot_rows);
+}
+
+
+/*
+  Is it ok to switch to a new engine for this table
+
+  SYNOPSIS
+    can_switch_engine()
+
+  RETURN VALUE
+    TRUE                  Ok
+    FALSE                 Not ok
+
+  DESCRIPTION
+    Used to ensure that tables with foreign key constraints are not moved
+    to engines without foreign key support.
+*/
+
+bool ha_partition::can_switch_engines()
+{
+  handler **file;
+  DBUG_ENTER("ha_partition::can_switch_engines");
+
+  file= m_file;
+  do
+  {
+    if (!(*file)->can_switch_engines())
+      DBUG_RETURN(FALSE);
+  } while (*(++file));
+  DBUG_RETURN(TRUE);
+}
+
+
+/*
+  Is table cache supported
+
+  SYNOPSIS
+    table_cache_type()
+
+*/
+
+uint8 ha_partition::table_cache_type()
+{
+  DBUG_ENTER("ha_partition::table_cache_type");
+
+  DBUG_RETURN(get_open_file_sample()->table_cache_type());
+}
+
+
+/**
+  Calculate hash value for KEY partitioning using an array of fields.
+
+  @param field_array   An array of the fields in KEY partitioning
+
+  @return hash_value calculated
+
+  @note Uses the hash function on the character set of the field.
+  Integer and floating point fields use the binary character set by default.
+*/
+
+uint32 ha_partition::calculate_key_hash_value(Field **field_array)
+{
+  ulong nr1= 1;
+  ulong nr2= 4;
+  bool use_51_hash;
+  use_51_hash= MY_TEST((*field_array)->table->part_info->key_algorithm ==
+                       partition_info::KEY_ALGORITHM_51);
+
+  do
+  {
+    Field *field= *field_array;
+    if (use_51_hash)
+    {
+      switch (field->real_type()) {
+      case MYSQL_TYPE_TINY:
+      case MYSQL_TYPE_SHORT:
+      case MYSQL_TYPE_LONG:
+      case MYSQL_TYPE_FLOAT:
+      case MYSQL_TYPE_DOUBLE:
+      case MYSQL_TYPE_NEWDECIMAL:
+      case MYSQL_TYPE_TIMESTAMP:
+      case MYSQL_TYPE_LONGLONG:
+      case MYSQL_TYPE_INT24:
+      case MYSQL_TYPE_TIME:
+      case MYSQL_TYPE_DATETIME:
+      case MYSQL_TYPE_YEAR:
+      case MYSQL_TYPE_NEWDATE:
+        {
+          if (field->is_null())
+          {
+            nr1^= (nr1 << 1) | 1;
+            continue;
+          }
+          /* Force this to my_hash_sort_bin, which was used in 5.1! */
+          uint len= field->pack_length();
+          my_charset_bin.hash_sort(field->ptr, len, &nr1, &nr2);
+          /* Done with this field, continue with next one. */
+          continue;
+        }
+      case MYSQL_TYPE_STRING:
+      case MYSQL_TYPE_VARCHAR:
+      case MYSQL_TYPE_BIT:
+        /* Not affected, same in 5.1 and 5.5 */
+        break;
+      /*
+        ENUM/SET uses my_hash_sort_simple in 5.1 (i.e. my_charset_latin1)
+        and my_hash_sort_bin in 5.5!
+      */
+      case MYSQL_TYPE_ENUM:
+      case MYSQL_TYPE_SET:
+        {
+          if (field->is_null())
+          {
+            nr1^= (nr1 << 1) | 1;
+            continue;
+          }
+          /* Force this to my_hash_sort_bin, which was used in 5.1! */
+          uint len= field->pack_length();
+          my_charset_latin1.hash_sort(field->ptr, len, &nr1, &nr2);
+          continue;
+        }
+      /* New types in mysql-5.6. */
+      case MYSQL_TYPE_DATETIME2:
+      case MYSQL_TYPE_TIME2:
+      case MYSQL_TYPE_TIMESTAMP2:
+        /* Not affected, 5.6+ only! */
+        break;
+
+      /* These types should not be allowed for partitioning! */
+      case MYSQL_TYPE_NULL:
+      case MYSQL_TYPE_DECIMAL:
+      case MYSQL_TYPE_DATE:
+      case MYSQL_TYPE_TINY_BLOB:
+      case MYSQL_TYPE_MEDIUM_BLOB:
+      case MYSQL_TYPE_LONG_BLOB:
+      case MYSQL_TYPE_BLOB:
+      case MYSQL_TYPE_VAR_STRING:
+      case MYSQL_TYPE_GEOMETRY:
+        /* fall through */
+      default:
+        DBUG_ASSERT(0);                    // New type?
+        /* Fall through for default hashing (5.5). */
+      }
+      /* fall through, use collation based hashing. */
+    }
+    field->hash(&nr1, &nr2);
+  } while (*(++field_array));
+  return (uint32) nr1;
+}
+
+
+/****************************************************************************
+                MODULE print messages
+****************************************************************************/
+
+const char *ha_partition::index_type(uint inx)
+{
+  uint first_used_partition;
+  DBUG_ENTER("ha_partition::index_type");
+
+  first_used_partition= bitmap_get_first_set(&(m_part_info->read_partitions));
+
+  if (first_used_partition == MY_BIT_NONE)
+  {
+    DBUG_ASSERT(0);                             // How can this happen?
+    DBUG_RETURN(handler::index_type(inx));
+  }
+
+  DBUG_RETURN(m_file[first_used_partition]->index_type(inx));
+}
+
+
+enum row_type ha_partition::get_row_type() const
+{
+  uint i;
+  enum row_type type;
+  DBUG_ENTER("ha_partition::get_row_type");
+
+  i= bitmap_get_first_set(&m_part_info->read_partitions);
+  DBUG_ASSERT(i < m_tot_parts);
+  if (i >= m_tot_parts)
+    DBUG_RETURN(ROW_TYPE_NOT_USED);
+
+  type= m_file[i]->get_row_type();
+  DBUG_PRINT("info", ("partition %u, row_type: %d", i, type));
+
+  for (i= bitmap_get_next_set(&m_part_info->lock_partitions, i);
+       i < m_tot_parts;
+       i= bitmap_get_next_set(&m_part_info->lock_partitions, i))
+  {
+    enum row_type part_type= m_file[i]->get_row_type();
+    DBUG_PRINT("info", ("partition %u, row_type: %d", i, type));
+    if (part_type != type)
+      DBUG_RETURN(ROW_TYPE_NOT_USED);
+  }
+
+  DBUG_RETURN(type);
+}
+
+
+void ha_partition::append_row_to_str(String &str)
+{
+  const uchar *rec;
+  bool is_rec0= !m_err_rec || m_err_rec == table->record[0];
+  if (is_rec0)
+    rec= table->record[0];
+  else
+    rec= m_err_rec;
+  // If PK, use full PK instead of full part field array!
+  if (table->s->primary_key != MAX_KEY)
+  {
+    KEY *key= table->key_info + table->s->primary_key;
+    KEY_PART_INFO *key_part=     key->key_part;
+    KEY_PART_INFO *key_part_end= key_part + key->user_defined_key_parts;
+    if (!is_rec0)
+      set_key_field_ptr(key, rec, table->record[0]);
+    for (; key_part != key_part_end; key_part++)
+    {
+      Field *field= key_part->field;
+      str.append(" ");
+      str.append(&field->field_name);
+      str.append(":");
+      field_unpack(&str, field, rec, 0, false);
+    }
+    if (!is_rec0)
+      set_key_field_ptr(key, table->record[0], rec);
+  }
+  else
+  {
+    Field **field_ptr;
+    if (!is_rec0)
+      table->move_fields(m_part_info->full_part_field_array, rec,
+                    table->record[0]);
+    /* No primary key, use full partition field array. */
+    for (field_ptr= m_part_info->full_part_field_array;
+         *field_ptr;
+         field_ptr++)
+    {
+      Field *field= *field_ptr;
+      str.append(" ");
+      str.append(&field->field_name);
+      str.append(":");
+      field_unpack(&str, field, rec, 0, false);
+    }
+    if (!is_rec0)
+      table->move_fields(m_part_info->full_part_field_array, table->record[0],
+                    rec);
+  }
+}
+
+
+void ha_partition::print_error(int error, myf errflag)
+{
+  THD *thd= ha_thd();
+  DBUG_ENTER("ha_partition::print_error");
+  DBUG_PRINT("enter", ("error: %d", error));
+
+  /* Should probably look for my own errors first */
+  if ((error == HA_ERR_NO_PARTITION_FOUND) &&
+      ! (thd->lex->alter_info.partition_flags & ALTER_PARTITION_TRUNCATE))
+  {
+    m_part_info->print_no_partition_found(table, errflag);
+    DBUG_VOID_RETURN;
+  }
+  else if (error == HA_ERR_ROW_IN_WRONG_PARTITION)
+  {
+    /* Should only happen on DELETE or UPDATE! */
+    DBUG_ASSERT(thd_sql_command(thd) == SQLCOM_DELETE ||
+                thd_sql_command(thd) == SQLCOM_DELETE_MULTI ||
+                thd_sql_command(thd) == SQLCOM_UPDATE ||
+                thd_sql_command(thd) == SQLCOM_UPDATE_MULTI);
+    DBUG_ASSERT(m_err_rec);
+    if (m_err_rec)
+    {
+      uint max_length;
+      char buf[MAX_KEY_LENGTH];
+      String str(buf,sizeof(buf),system_charset_info);
+      uint32 part_id;
+      str.length(0);
+      str.append("(");
+      str.append_ulonglong(m_last_part);
+      str.append(" != ");
+      if (get_part_for_buf(m_err_rec, m_rec0, m_part_info, &part_id))
+        str.append("?");
+      else
+        str.append_ulonglong(part_id);
+      str.append(")");
+      append_row_to_str(str);
+
+      /* Log this error, so the DBA can notice it and fix it! */
+      sql_print_error("Table '%-192s' corrupted: row in wrong partition: %s"
+                      "Please REPAIR the table!",
+                      table->s->table_name.str,
+                      str.c_ptr_safe());
+
+      max_length= (MYSQL_ERRMSG_SIZE -
+                   (uint) strlen(ER_THD(thd, ER_ROW_IN_WRONG_PARTITION)));
+      if (str.length() >= max_length)
+      {
+        str.length(max_length-4);
+        str.append(STRING_WITH_LEN("..."));
+      }
+      my_error(ER_ROW_IN_WRONG_PARTITION, MYF(0), str.c_ptr_safe());
+      m_err_rec= NULL;
+      DBUG_VOID_RETURN;
+    }
+    /* fall through to generic error handling. */
+  }
+
+  /*
+    We choose a main handler's print_error if:
+    * m_file has not been initialized, like in bug#42438
+    * lookup_errkey is set, which means that an error has occured in the
+      main handler, not in individual partitions
+  */
+  if (m_file && lookup_errkey == (uint)-1)
+  {
+    if (m_last_part >= m_tot_parts)
+    {
+      DBUG_ASSERT(0);
+      m_last_part= 0;
+    }
+    m_file[m_last_part]->print_error(error, errflag);
+  }
+  else
+    handler::print_error(error, errflag);
+  DBUG_VOID_RETURN;
+}
+
+
+bool ha_partition::get_error_message(int error, String *buf)
+{
+  DBUG_ENTER("ha_partition::get_error_message");
+
+  /* Should probably look for my own errors first */
+
+  /* In case m_file has not been initialized, like in bug#42438 */
+  if (m_file)
+    DBUG_RETURN(m_file[m_last_part]->get_error_message(error, buf));
+  DBUG_RETURN(handler::get_error_message(error, buf));
+
+}
+
+
+/****************************************************************************
+                MODULE in-place ALTER
+****************************************************************************/
+/**
+  Get table flags.
+*/
+
+handler::Table_flags ha_partition::table_flags() const
+{
+  uint first_used_partition= 0;
+  DBUG_ENTER("ha_partition::table_flags");
+  if (m_handler_status < handler_initialized ||
+      m_handler_status >= handler_closed)
+    DBUG_RETURN(PARTITION_ENABLED_TABLE_FLAGS);
+
+  if (get_lock_type() != F_UNLCK)
+  {
+    /*
+      The flags are cached after external_lock, and may depend on isolation
+      level. So we should use a locked partition to get the correct flags.
+    */
+    first_used_partition= bitmap_get_first_set(&m_part_info->lock_partitions);
+    if (first_used_partition == MY_BIT_NONE)
+      first_used_partition= 0;
+  }
+  DBUG_RETURN((m_file[first_used_partition]->ha_table_flags() &
+                 ~(PARTITION_DISABLED_TABLE_FLAGS)) |
+                 (PARTITION_ENABLED_TABLE_FLAGS));
+}
+
+
+/**
+  alter_table_flags must be on handler/table level, not on hton level
+  due to the ha_partition hton does not know what the underlying hton is.
+*/
+
+alter_table_operations ha_partition::alter_table_flags(alter_table_operations flags)
+{
+  alter_table_operations flags_to_return;
+  DBUG_ENTER("ha_partition::alter_table_flags");
+
+  flags_to_return= ht->alter_table_flags(flags);
+  flags_to_return|= m_file[0]->alter_table_flags(flags);
+
+  DBUG_RETURN(flags_to_return);
+}
+
+
+/**
+  check if copy of data is needed in alter table.
+*/
+bool ha_partition::check_if_incompatible_data(HA_CREATE_INFO *create_info,
+                                              uint table_changes)
+{
+  /*
+    The check for any partitioning related changes have already been done
+    in mysql_alter_table (by fix_partition_func), so it is only up to
+    the underlying handlers.
+  */
+  List_iterator<partition_element> part_it(m_part_info->partitions);
+  HA_CREATE_INFO dummy_info= *create_info;
+  uint i=0;
+  while (partition_element *part_elem= part_it++)
+  {
+    if (m_is_sub_partitioned)
+    {
+      List_iterator<partition_element> subpart_it(part_elem->subpartitions);
+      while (partition_element *sub_elem= subpart_it++)
+      {
+        dummy_info.data_file_name= sub_elem->data_file_name;
+        dummy_info.index_file_name= sub_elem->index_file_name;
+        if (m_file[i++]->check_if_incompatible_data(&dummy_info, table_changes))
+          return COMPATIBLE_DATA_NO;
+      }
+    }
+    else
+    {
+      dummy_info.data_file_name= part_elem->data_file_name;
+      dummy_info.index_file_name= part_elem->index_file_name;
+      if (m_file[i++]->check_if_incompatible_data(&dummy_info, table_changes))
+        return COMPATIBLE_DATA_NO;
+    }
+  }
+  return COMPATIBLE_DATA_YES;
+}
+
+
+/**
+  Support of in-place alter table.
+*/
+
+/**
+  Helper class for in-place alter, see handler.h
+*/
+
+class ha_partition_inplace_ctx : public inplace_alter_handler_ctx
+{
+public:
+  inplace_alter_handler_ctx **handler_ctx_array;
+private:
+  uint m_tot_parts;
+
+public:
+  ha_partition_inplace_ctx(THD *thd, uint tot_parts)
+    : inplace_alter_handler_ctx(),
+      handler_ctx_array(NULL),
+      m_tot_parts(tot_parts)
+  {}
+
+  ~ha_partition_inplace_ctx()
+  {
+    if (handler_ctx_array)
+    {
+      for (uint index= 0; index < m_tot_parts; index++)
+        delete handler_ctx_array[index];
+    }
+  }
+};
+
+
+enum_alter_inplace_result
+ha_partition::check_if_supported_inplace_alter(TABLE *altered_table,
+                                               Alter_inplace_info *ha_alter_info)
+{
+  uint index= 0;
+  enum_alter_inplace_result result;
+  alter_table_operations orig_ops;
+  ha_partition_inplace_ctx *part_inplace_ctx;
+  bool first_is_set= false;
+  THD *thd= ha_thd();
+
+  DBUG_ENTER("ha_partition::check_if_supported_inplace_alter");
+  /*
+    Support inplace change of KEY () -> KEY ALGORITHM = N ().
+    Any other change would set partition_changed in
+    prep_alter_part_table() in mysql_alter_table().
+  */
+  if (ha_alter_info->alter_info->partition_flags == ALTER_PARTITION_INFO)
+  {
+    DBUG_ASSERT(ha_alter_info->alter_info->flags == 0);
+    DBUG_RETURN(HA_ALTER_INPLACE_NO_LOCK);
+  }
+
+  part_inplace_ctx=
+    new (thd->mem_root) ha_partition_inplace_ctx(thd, m_tot_parts);
+  if (!part_inplace_ctx)
+    DBUG_RETURN(HA_ALTER_ERROR);
+
+  part_inplace_ctx->handler_ctx_array= (inplace_alter_handler_ctx **)
+    thd->alloc(sizeof(inplace_alter_handler_ctx *) * (m_tot_parts + 1));
+  if (!part_inplace_ctx->handler_ctx_array)
+    DBUG_RETURN(HA_ALTER_ERROR);
+
+  do {
+    result= HA_ALTER_INPLACE_NO_LOCK;
+    /* Set all to NULL, including the terminating one. */
+    for (index= 0; index <= m_tot_parts; index++)
+       part_inplace_ctx->handler_ctx_array[index]= NULL;
+
+    ha_alter_info->handler_flags |= ALTER_PARTITIONED;
+    orig_ops= ha_alter_info->handler_flags;
+    for (index= 0; index < m_tot_parts; index++)
+    {
+      enum_alter_inplace_result p_result=
+        m_file[index]->check_if_supported_inplace_alter(altered_table,
+                                                        ha_alter_info);
+      part_inplace_ctx->handler_ctx_array[index]= ha_alter_info->handler_ctx;
+
+      if (index == 0)
+        first_is_set= (ha_alter_info->handler_ctx != NULL);
+      else if (first_is_set != (ha_alter_info->handler_ctx != NULL))
+      {
+        /* Either none or all partitions must set handler_ctx! */
+        DBUG_ASSERT(0);
+        DBUG_RETURN(HA_ALTER_ERROR);
+      }
+      if (p_result < result)
+        result= p_result;
+      if (result == HA_ALTER_ERROR)
+        break;
+    }
+  } while (orig_ops != ha_alter_info->handler_flags);
+
+  ha_alter_info->handler_ctx= part_inplace_ctx;
+  /*
+    To indicate for future inplace calls that there are several
+    partitions/handlers that need to be committed together,
+    we set group_commit_ctx to the NULL terminated array of
+    the partitions handlers.
+  */
+  ha_alter_info->group_commit_ctx= part_inplace_ctx->handler_ctx_array;
+
+  DBUG_RETURN(result);
+}
+
+
+bool ha_partition::prepare_inplace_alter_table(TABLE *altered_table,
+                                               Alter_inplace_info *ha_alter_info)
+{
+  uint index= 0;
+  bool error= false;
+  ha_partition_inplace_ctx *part_inplace_ctx;
+
+  DBUG_ENTER("ha_partition::prepare_inplace_alter_table");
+
+  /*
+    Changing to similar partitioning, only update metadata.
+    Non allowed changes would be caought in prep_alter_part_table().
+  */
+  if (ha_alter_info->alter_info->partition_flags == ALTER_PARTITION_INFO)
+  {
+    DBUG_ASSERT(ha_alter_info->alter_info->flags == 0);
+    DBUG_RETURN(false);
+  }
+
+  part_inplace_ctx=
+    static_cast<class ha_partition_inplace_ctx*>(ha_alter_info->handler_ctx);
+
+  for (index= 0; index < m_tot_parts && !error; index++)
+  {
+    ha_alter_info->handler_ctx= part_inplace_ctx->handler_ctx_array[index];
+    if (m_file[index]->ha_prepare_inplace_alter_table(altered_table,
+                                                      ha_alter_info))
+      error= true;
+    part_inplace_ctx->handler_ctx_array[index]= ha_alter_info->handler_ctx;
+  }
+  ha_alter_info->handler_ctx= part_inplace_ctx;
+
+  DBUG_RETURN(error);
+}
+
+
+bool ha_partition::inplace_alter_table(TABLE *altered_table,
+                                       Alter_inplace_info *ha_alter_info)
+{
+  uint index= 0;
+  bool error= false;
+  ha_partition_inplace_ctx *part_inplace_ctx;
+
+  DBUG_ENTER("ha_partition::inplace_alter_table");
+
+  /*
+    Changing to similar partitioning, only update metadata.
+    Non allowed changes would be caught in prep_alter_part_table().
+  */
+  if (ha_alter_info->alter_info->partition_flags == ALTER_PARTITION_INFO)
+  {
+    DBUG_ASSERT(ha_alter_info->alter_info->flags == 0);
+    DBUG_RETURN(false);
+  }
+
+  part_inplace_ctx=
+    static_cast<class ha_partition_inplace_ctx*>(ha_alter_info->handler_ctx);
+
+  for (index= 0; index < m_tot_parts && !error; index++)
+  {
+    if ((ha_alter_info->handler_ctx=
+	 part_inplace_ctx->handler_ctx_array[index]) != NULL
+	&& index != 0)
+      ha_alter_info->handler_ctx->set_shared_data
+	(*part_inplace_ctx->handler_ctx_array[index - 1]);
+
+    if (m_file[index]->ha_inplace_alter_table(altered_table,
+                                              ha_alter_info))
+      error= true;
+    part_inplace_ctx->handler_ctx_array[index]= ha_alter_info->handler_ctx;
+  }
+  ha_alter_info->handler_ctx= part_inplace_ctx;
+
+  DBUG_RETURN(error);
+}
+
+
+/*
+  Note that this function will try rollback failed ADD INDEX by
+  executing DROP INDEX for the indexes that were committed (if any)
+  before the error occurred. This means that the underlying storage
+  engine must be able to drop index in-place with X-lock held.
+  (As X-lock will be held here if new indexes are to be committed)
+*/
+bool ha_partition::commit_inplace_alter_table(TABLE *altered_table,
+                                              Alter_inplace_info *ha_alter_info,
+                                              bool commit)
+{
+  ha_partition_inplace_ctx *part_inplace_ctx;
+  bool error= false;
+
+  DBUG_ENTER("ha_partition::commit_inplace_alter_table");
+
+  /*
+    Changing to similar partitioning, only update metadata.
+    Non allowed changes would be caught in prep_alter_part_table().
+  */
+  if (ha_alter_info->alter_info->partition_flags == ALTER_PARTITION_INFO)
+  {
+    DBUG_ASSERT(ha_alter_info->alter_info->flags == 0);
+    DBUG_RETURN(false);
+  }
+
+  part_inplace_ctx=
+    static_cast<class ha_partition_inplace_ctx*>(ha_alter_info->handler_ctx);
+
+  if (commit)
+  {
+    DBUG_ASSERT(ha_alter_info->group_commit_ctx ==
+                part_inplace_ctx->handler_ctx_array);
+    ha_alter_info->handler_ctx= part_inplace_ctx->handler_ctx_array[0];
+    error= m_file[0]->ha_commit_inplace_alter_table(altered_table,
+                                                    ha_alter_info, commit);
+    if (unlikely(error))
+      goto end;
+    if (ha_alter_info->group_commit_ctx)
+    {
+      /*
+        If ha_alter_info->group_commit_ctx is not set to NULL,
+        then the engine did only commit the first partition!
+        The engine is probably new, since both innodb and the default
+        implementation of handler::commit_inplace_alter_table sets it to NULL
+        and simply return false, since it allows metadata changes only.
+        Loop over all other partitions as to follow the protocol!
+      */
+      uint i;
+      DBUG_ASSERT(0);
+      for (i= 1; i < m_tot_parts; i++)
+      {
+        ha_alter_info->handler_ctx= part_inplace_ctx->handler_ctx_array[i];
+        error|= m_file[i]->ha_commit_inplace_alter_table(altered_table,
+                                                         ha_alter_info,
+                                                         true);
+      }
+  }
+    }
+  else
+  {
+    uint i;
+    for (i= 0; i < m_tot_parts; i++)
+    {
+      /* Rollback, commit == false,  is done for each partition! */
+      ha_alter_info->handler_ctx= part_inplace_ctx->handler_ctx_array[i];
+      if (m_file[i]->ha_commit_inplace_alter_table(altered_table,
+                                                   ha_alter_info, false))
+        error= true;
+      }
+    }
+end:
+  ha_alter_info->handler_ctx= part_inplace_ctx;
+
+  DBUG_RETURN(error);
+}
+
+
+uint ha_partition::min_of_the_max_uint(
+                       uint (handler::*operator_func)(void) const) const
+{
+  handler **file;
+  uint min_of_the_max= ((*m_file)->*operator_func)();
+
+  for (file= m_file+1; *file; file++)
+  {
+    uint tmp= ((*file)->*operator_func)();
+    set_if_smaller(min_of_the_max, tmp);
+  }
+  return min_of_the_max;
+}
+
+
+uint ha_partition::max_supported_key_parts() const
+{
+  return min_of_the_max_uint(&handler::max_supported_key_parts);
+}
+
+
+uint ha_partition::max_supported_key_length() const
+{
+  return min_of_the_max_uint(&handler::max_supported_key_length);
+}
+
+
+uint ha_partition::max_supported_key_part_length() const
+{
+  return min_of_the_max_uint(&handler::max_supported_key_part_length);
+}
+
+
+uint ha_partition::max_supported_record_length() const
+{
+  return min_of_the_max_uint(&handler::max_supported_record_length);
+}
+
+
+uint ha_partition::max_supported_keys() const
+{
+  return min_of_the_max_uint(&handler::max_supported_keys);
+}
+
+
+uint ha_partition::min_record_length(uint options) const
+{
+  handler **file;
+  uint max= (*m_file)->min_record_length(options);
+
+  for (file= m_file, file++; *file; file++)
+    if (max < (*file)->min_record_length(options))
+      max= (*file)->min_record_length(options);
+  return max;
+}
+
+/****************************************************************************
+                MODULE compare records
+****************************************************************************/
+/*
+  Compare two positions
+
+  SYNOPSIS
+    cmp_ref()
+    ref1                   First position
+    ref2                   Second position
+
+  RETURN VALUE
+    <0                     ref1 < ref2
+    0                      Equal
+    >0                     ref1 > ref2
+
+  DESCRIPTION
+    We get two references and need to check if those records are the same.
+    If they belong to different partitions we decide that they are not
+    the same record. Otherwise we use the particular handler to decide if
+    they are the same. Sort in partition id order if not equal.
+
+  MariaDB note:
+    Please don't merge the code from MySQL that does this:
+
+    We get two references and need to check if those records are the same.
+    If they belong to different partitions we decide that they are not
+    the same record. Otherwise we use the particular handler to decide if
+    they are the same. Sort in partition id order if not equal.
+
+    It is incorrect, MariaDB has an alternative fix.
+*/
+
+int ha_partition::cmp_ref(const uchar *ref1, const uchar *ref2)
+{
+  int cmp;
+  uint32 diff1, diff2;
+  DBUG_ENTER("ha_partition::cmp_ref");
+
+  cmp= get_open_file_sample()->cmp_ref((ref1 + PARTITION_BYTES_IN_POS),
+                                       (ref2 + PARTITION_BYTES_IN_POS));
+  if (cmp)
+    DBUG_RETURN(cmp);
+
+  diff2= uint2korr(ref2);
+  diff1= uint2korr(ref1);
+
+  if (diff1 == diff2)
+  {
+   /* This means that the references are same and are in same partition.*/
+    DBUG_RETURN(0);
+  }
+
+  /*
+    In Innodb we compare with either primary key value or global DB_ROW_ID so
+    it is not possible that the two references are equal and are in different
+    partitions, but in myisam it is possible since we are comparing offsets.
+    Remove this assert if DB_ROW_ID is changed to be per partition.
+  */
+  DBUG_ASSERT(!m_innodb);
+  DBUG_RETURN(diff2 > diff1 ? -1 : 1);
+}
+
+
+/****************************************************************************
+                MODULE auto increment
+****************************************************************************/
+
+
+/**
+   Retreive new values for part_share->next_auto_inc_val if needed
+
+   This is needed if the value has not been initialized or if one of
+   the underlying partitions require that the value should be re-calculated
+*/
+
+void ha_partition::update_next_auto_inc_val()
+{
+  if (!part_share->auto_inc_initialized ||
+      need_info_for_auto_inc())
+    info(HA_STATUS_AUTO);
+}
+
+
+/**
+  Determine whether a partition needs auto-increment initialization.
+
+  @return
+    TRUE                    A  partition needs auto-increment initialization
+    FALSE                   No partition needs auto-increment initialization
+
+  Resets part_share->auto_inc_initialized if next auto_increment needs to be
+  recalculated.
+*/
+
+bool ha_partition::need_info_for_auto_inc()
+{
+  handler **file= m_file;
+  DBUG_ENTER("ha_partition::need_info_for_auto_inc");
+
+  do
+  {
+    if ((*file)->need_info_for_auto_inc())
+    {
+      /* We have to get new auto_increment values from handler */
+      part_share->auto_inc_initialized= FALSE;
+      DBUG_RETURN(TRUE);
+    }
+  } while (*(++file));
+  DBUG_RETURN(FALSE);
+}
+
+
+/**
+  Determine if all partitions can use the current auto-increment value for
+  auto-increment initialization.
+
+  @return
+    TRUE                    All partitions can use the current auto-increment
+                            value for auto-increment initialization
+    FALSE                   All partitions cannot use the current
+                            auto-increment value for auto-increment
+                            initialization
+
+  Notes
+    This function is only called for ::info(HA_STATUS_AUTO) and is
+    mainly used by the Spider engine, which returns false
+    except in the case of DROP TABLE or ALTER TABLE when it returns TRUE.
+    Other engines always returns TRUE for this call.
+*/
+
+bool ha_partition::can_use_for_auto_inc_init()
+{
+  handler **file= m_file;
+  DBUG_ENTER("ha_partition::can_use_for_auto_inc_init");
+
+  do
+  {
+    if (!(*file)->can_use_for_auto_inc_init())
+      DBUG_RETURN(FALSE);
+  } while (*(++file));
+  DBUG_RETURN(TRUE);
+}
+
+
+int ha_partition::reset_auto_increment(ulonglong value)
+{
+  handler **file= m_file;
+  int res;
+  DBUG_ENTER("ha_partition::reset_auto_increment");
+  lock_auto_increment();
+  part_share->auto_inc_initialized= false;
+  part_share->next_auto_inc_val= 0;
+  do
+  {
+    if ((res= (*file)->ha_reset_auto_increment(value)) != 0)
+      break;
+  } while (*(++file));
+  unlock_auto_increment();
+  DBUG_RETURN(res);
+}
+
+
+/**
+  This method is called by update_auto_increment which in turn is called
+  by the individual handlers as part of write_row. We use the
+  part_share->next_auto_inc_val, or search all
+  partitions for the highest auto_increment_value if not initialized or
+  if auto_increment field is a secondary part of a key, we must search
+  every partition when holding a mutex to be sure of correctness.
+*/
+
+void ha_partition::get_auto_increment(ulonglong offset, ulonglong increment,
+                                      ulonglong nb_desired_values,
+                                      ulonglong *first_value,
+                                      ulonglong *nb_reserved_values)
+{
+  DBUG_ENTER("ha_partition::get_auto_increment");
+  DBUG_PRINT("enter", ("offset: %lu  inc: %lu  desired_values: %lu  "
+                       "first_value: %lu", (ulong) offset, (ulong) increment,
+                      (ulong) nb_desired_values, (ulong) *first_value));
+  DBUG_ASSERT(increment);
+  DBUG_ASSERT(nb_desired_values);
+  *first_value= 0;
+  if (table->s->next_number_keypart)
+  {
+    /*
+      next_number_keypart is != 0 if the auto_increment column is a secondary
+      column in the index (it is allowed in MyISAM)
+    */
+    DBUG_PRINT("info", ("next_number_keypart != 0"));
+    ulonglong nb_reserved_values_part;
+    ulonglong first_value_part, max_first_value;
+    handler **file= m_file;
+    first_value_part= max_first_value= *first_value;
+    /* Must find highest value among all partitions. */
+    do
+    {
+      /* Only nb_desired_values = 1 makes sense */
+      (*file)->get_auto_increment(offset, increment, 1,
+                                 &first_value_part, &nb_reserved_values_part);
+      if (unlikely(first_value_part == ULONGLONG_MAX)) // error in one partition
+      {
+        *first_value= first_value_part;
+        /* log that the error was between table/partition handler */
+        sql_print_error("Partition failed to reserve auto_increment value");
+        DBUG_VOID_RETURN;
+      }
+      DBUG_PRINT("info", ("first_value_part: %lu", (ulong) first_value_part));
+      set_if_bigger(max_first_value, first_value_part);
+    } while (*(++file));
+    *first_value= max_first_value;
+    *nb_reserved_values= 1;
+  }
+  else
+  {
+    THD *thd= ha_thd();
+    /*
+      This is initialized in the beginning of the first write_row call.
+    */
+    DBUG_ASSERT(part_share->auto_inc_initialized);
+    /*
+      Get a lock for handling the auto_increment in part_share
+      for avoiding two concurrent statements getting the same number.
+    */
+
+    lock_auto_increment();
+
+    /*
+      In a multi-row insert statement like INSERT SELECT and LOAD DATA
+      where the number of candidate rows to insert is not known in advance
+      we must hold a lock/mutex for the whole statement if we have statement
+      based replication. Because the statement-based binary log contains
+      only the first generated value used by the statement, and slaves assumes
+      all other generated values used by this statement were consecutive to
+      this first one, we must exclusively lock the generator until the
+      statement is done.
+    */
+    if (!auto_increment_safe_stmt_log_lock &&
+        thd->lex->sql_command != SQLCOM_INSERT &&
+        mysql_bin_log.is_open() &&
+        !thd->is_current_stmt_binlog_format_row() &&
+        (thd->variables.option_bits & OPTION_BIN_LOG))
+    {
+      DBUG_PRINT("info", ("locking auto_increment_safe_stmt_log_lock"));
+      auto_increment_safe_stmt_log_lock= TRUE;
+    }
+
+    /* this gets corrected (for offset/increment) in update_auto_increment */
+    *first_value= part_share->next_auto_inc_val;
+    part_share->next_auto_inc_val+= nb_desired_values * increment;
+
+    unlock_auto_increment();
+    DBUG_PRINT("info", ("*first_value: %lu", (ulong) *first_value));
+    *nb_reserved_values= nb_desired_values;
+  }
+  DBUG_VOID_RETURN;
+}
+
+void ha_partition::release_auto_increment()
+{
+  DBUG_ENTER("ha_partition::release_auto_increment");
+
+  if (table->s->next_number_keypart)
+  {
+    uint i;
+    for (i= bitmap_get_first_set(&m_part_info->lock_partitions);
+         i < m_tot_parts;
+         i= bitmap_get_next_set(&m_part_info->lock_partitions, i))
+    {
+      m_file[i]->ha_release_auto_increment();
+    }
+  }
+  else
+  {
+    lock_auto_increment();
+    if (next_insert_id)
+    {
+      ulonglong next_auto_inc_val= part_share->next_auto_inc_val;
+      /*
+        If the current auto_increment values is lower than the reserved
+        value, and the reserved value was reserved by this thread,
+        we can lower the reserved value.
+      */
+      if (next_insert_id < next_auto_inc_val &&
+          auto_inc_interval_for_cur_row.maximum() >= next_auto_inc_val)
+      {
+        THD *thd= ha_thd();
+        /*
+          Check that we do not lower the value because of a failed insert
+          with SET INSERT_ID, i.e. forced/non generated values.
+        */
+        if (thd->auto_inc_intervals_forced.maximum() < next_insert_id)
+          part_share->next_auto_inc_val= next_insert_id;
+      }
+      DBUG_PRINT("info", ("part_share->next_auto_inc_val: %lu",
+                          (ulong) part_share->next_auto_inc_val));
+    }
+    /*
+      Unlock the multi-row statement lock taken in get_auto_increment.
+      These actions must be performed even if the next_insert_id field
+      contains zero, otherwise if the update_auto_increment fails then
+      an unnecessary lock will remain:
+    */
+    if (auto_increment_safe_stmt_log_lock)
+    {
+      auto_increment_safe_stmt_log_lock= FALSE;
+      DBUG_PRINT("info", ("unlocking auto_increment_safe_stmt_log_lock"));
+    }
+
+    unlock_auto_increment();
+  }
+  DBUG_VOID_RETURN;
+}
+
+/****************************************************************************
+                MODULE initialize handler for HANDLER call
+****************************************************************************/
+
+void ha_partition::init_table_handle_for_HANDLER()
+{
+  return;
+}
+
+
+/**
+  Calculate the checksum of the table (all partitions)
+*/
+
+int ha_partition::pre_calculate_checksum()
+{
+  int error;
+  DBUG_ENTER("ha_partition::pre_calculate_checksum");
+  m_pre_calling= TRUE;
+  if ((table_flags() & (HA_HAS_OLD_CHECKSUM | HA_HAS_NEW_CHECKSUM)))
+  {
+    handler **file= m_file;
+    do
+    {
+      if ((error= (*file)->pre_calculate_checksum()))
+      {
+        DBUG_RETURN(error);
+      }
+    } while (*(++file));
+  }
+  DBUG_RETURN(0);
+}
+
+
+int ha_partition::calculate_checksum()
+{
+  int error;
+  stats.checksum= 0;
+  stats.checksum_null= TRUE;
+
+  DBUG_ENTER("ha_partition::calculate_checksum");
+  if (!m_pre_calling)
+  {
+    if ((error= pre_calculate_checksum()))
+    {
+      m_pre_calling= FALSE;
+      DBUG_RETURN(error);
+    }
+  }
+  m_pre_calling= FALSE;
+
+  handler **file= m_file;
+  do
+  {
+    if ((error= (*file)->calculate_checksum()))
+    {
+      DBUG_RETURN(error);
+    }
+    if (!(*file)->stats.checksum_null)
+    {
+      stats.checksum+= (*file)->stats.checksum;
+      stats.checksum_null= FALSE;
+    }
+  } while (*(++file));
+  DBUG_RETURN(0);
+}
+
+
+/****************************************************************************
+                MODULE enable/disable indexes
+****************************************************************************/
+
+/*
+  Disable indexes for a while
+  SYNOPSIS
+    disable_indexes()
+    mode                      Mode
+  RETURN VALUES
+    0                         Success
+    != 0                      Error
+*/
+
+int ha_partition::disable_indexes(uint mode)
+{
+  handler **file;
+  int error= 0;
+
+  DBUG_ASSERT(bitmap_is_set_all(&(m_part_info->lock_partitions)));
+  for (file= m_file; *file; file++)
+  {
+    if (unlikely((error= (*file)->ha_disable_indexes(mode))))
+      break;
+  }
+  return error;
+}
+
+
+/*
+  Enable indexes again
+  SYNOPSIS
+    enable_indexes()
+    mode                      Mode
+  RETURN VALUES
+    0                         Success
+    != 0                      Error
+*/
+
+int ha_partition::enable_indexes(uint mode)
+{
+  handler **file;
+  int error= 0;
+
+  DBUG_ASSERT(bitmap_is_set_all(&(m_part_info->lock_partitions)));
+  for (file= m_file; *file; file++)
+  {
+    if (unlikely((error= (*file)->ha_enable_indexes(mode))))
+      break;
+  }
+  return error;
+}
+
+
+/*
+  Check if indexes are disabled
+  SYNOPSIS
+    indexes_are_disabled()
+
+  RETURN VALUES
+    0                      Indexes are enabled
+    != 0                   Indexes are disabled
+*/
+
+int ha_partition::indexes_are_disabled(void)
+{
+  handler **file;
+  int error= 0;
+
+  DBUG_ASSERT(bitmap_is_set_all(&(m_part_info->lock_partitions)));
+  for (file= m_file; *file; file++)
+  {
+    if (unlikely((error= (*file)->indexes_are_disabled())))
+      break;
+  }
+  return error;
+}
+
+
+/**
+  Check/fix misplaced rows.
+
+  @param read_part_id  Partition to check/fix.
+  @param repair        If true, move misplaced rows to correct partition.
+
+  @return Operation status.
+    @retval HA_ADMIN_OK     Success
+    @retval != HA_ADMIN_OK  Error
+*/
+
+int ha_partition::check_misplaced_rows(uint read_part_id, bool do_repair)
+{
+  int result= 0;
+  uint32 correct_part_id;
+  longlong func_value;
+  longlong num_misplaced_rows= 0;
+
+  DBUG_ENTER("ha_partition::check_misplaced_rows");
+
+  DBUG_ASSERT(m_file);
+
+  if (m_part_info->vers_info &&
+      read_part_id != m_part_info->vers_info->now_part->id &&
+      !m_part_info->vers_info->interval.is_set())
+  {
+    print_admin_msg(ha_thd(), MYSQL_ERRMSG_SIZE, "note",
+                    table_share->db.str, table->alias,
+                    opt_op_name[CHECK_PARTS],
+                    "Not supported for non-INTERVAL history partitions");
+    DBUG_RETURN(HA_ADMIN_NOT_IMPLEMENTED);
+  }
+
+  if (do_repair)
+  {
+    /* We must read the full row, if we need to move it! */
+    bitmap_set_all(table->read_set);
+    bitmap_set_all(table->write_set);
+  }
+  else
+  {
+    /* Only need to read the partitioning fields. */
+    bitmap_union(table->read_set, &m_part_info->full_part_field_set);
+  }
+
+  if ((result= m_file[read_part_id]->ha_rnd_init(1)))
+    DBUG_RETURN(result);
+
+  while (true)
+  {
+    if ((result= m_file[read_part_id]->ha_rnd_next(m_rec0)))
+    {
+      if (result != HA_ERR_END_OF_FILE)
+        break;
+
+      if (num_misplaced_rows > 0)
+      {
+	print_admin_msg(ha_thd(), MYSQL_ERRMSG_SIZE, "warning",
+                        table_share->db.str, table->alias,
+                        opt_op_name[REPAIR_PARTS],
+                        "Moved %lld misplaced rows",
+                        num_misplaced_rows);
+      }
+      /* End-of-file reached, all rows are now OK, reset result and break. */
+      result= 0;
+      break;
+    }
+
+    result= m_part_info->get_partition_id(m_part_info, &correct_part_id,
+                                          &func_value);
+    if (result)
+      break;
+
+    if (correct_part_id != read_part_id)
+    {
+      num_misplaced_rows++;
+      if (!do_repair)
+      {
+        /* Check. */
+	print_admin_msg(ha_thd(), MYSQL_ERRMSG_SIZE, "error",
+                        table_share->db.str, table->alias,
+                        opt_op_name[CHECK_PARTS],
+                        "Found a misplaced row");
+        /* Break on first misplaced row! */
+        result= HA_ADMIN_NEEDS_UPGRADE;
+        break;
+      }
+      else
+      {
+        DBUG_PRINT("info", ("Moving row from partition %u to %u",
+                            (uint) read_part_id, (uint) correct_part_id));
+
+        /*
+          Insert row into correct partition. Notice that there are no commit
+          for every N row, so the repair will be one large transaction!
+        */
+        if ((result= m_file[correct_part_id]->ha_write_row(m_rec0)))
+        {
+          /*
+            We have failed to insert a row, it might have been a duplicate!
+          */
+          char buf[MAX_KEY_LENGTH];
+          String str(buf,sizeof(buf),system_charset_info);
+          str.length(0);
+          if (result == HA_ERR_FOUND_DUPP_KEY)
+          {
+            str.append("Duplicate key found, "
+                       "please update or delete the record:\n");
+            result= HA_ADMIN_CORRUPT;
+          }
+          m_err_rec= NULL;
+          append_row_to_str(str);
+
+          /*
+            If the engine supports transactions, the failure will be
+            rolled back
+          */
+          if (!m_file[correct_part_id]->has_transactions_and_rollback())
+          {
+            /* Log this error, so the DBA can notice it and fix it! */
+            sql_print_error("Table '%-192s' failed to move/insert a row"
+                            " from part %u into part %u:\n%s",
+                            table->s->table_name.str,
+                            (uint) read_part_id,
+                            (uint) correct_part_id,
+                            str.c_ptr_safe());
+          }
+	  print_admin_msg(ha_thd(), MYSQL_ERRMSG_SIZE, "error",
+                          table_share->db.str, table->alias,
+                          opt_op_name[REPAIR_PARTS],
+                          "Failed to move/insert a row"
+                          " from part %u into part %u:\n%s",
+                          (uint) read_part_id,
+                          (uint) correct_part_id,
+                          str.c_ptr_safe());
+          break;
+        }
+
+        /* Delete row from wrong partition. */
+        if ((result= m_file[read_part_id]->ha_delete_row(m_rec0)))
+        {
+          if (m_file[correct_part_id]->has_transactions_and_rollback())
+            break;
+          /*
+            We have introduced a duplicate, since we failed to remove it
+            from the wrong partition.
+          */
+          char buf[MAX_KEY_LENGTH];
+          String str(buf,sizeof(buf),system_charset_info);
+          str.length(0);
+          m_err_rec= NULL;
+          append_row_to_str(str);
+
+          /* Log this error, so the DBA can notice it and fix it! */
+          sql_print_error("Table '%-192s': Delete from part %u failed with"
+                          " error %d. But it was already inserted into"
+                          " part %u, when moving the misplaced row!"
+                          "\nPlease manually fix the duplicate row:\n%s",
+                          table->s->table_name.str,
+                          (uint) read_part_id,
+                          result,
+                          (uint) correct_part_id,
+                          str.c_ptr_safe());
+          break;
+        }
+      }
+    }
+  }
+
+  int tmp_result= m_file[read_part_id]->ha_rnd_end();
+  DBUG_RETURN(result ? result : tmp_result);
+}
+
+
+#define KEY_PARTITIONING_CHANGED_STR \
+  "KEY () partitioning changed, please run:\n" \
+  "ALTER TABLE %s.%s ALGORITHM = INPLACE %s"
+
+int ha_partition::check_for_upgrade(HA_CHECK_OPT *check_opt)
+{
+  int error= HA_ADMIN_NEEDS_CHECK;
+  DBUG_ENTER("ha_partition::check_for_upgrade");
+
+  /*
+    This is called even without FOR UPGRADE,
+    if the .frm version is lower than the current version.
+    In that case return that it needs checking!
+  */
+  if (!(check_opt->sql_flags & TT_FOR_UPGRADE))
+    DBUG_RETURN(error);
+
+  /*
+    Partitions will be checked for during their ha_check!
+
+    Check if KEY (sub)partitioning was used and any field's hash calculation
+    differs from 5.1, see bug#14521864.
+  */
+  if (table->s->mysql_version < 50503 &&              // 5.1 table (<5.5.3)
+      ((m_part_info->part_type == HASH_PARTITION &&   // KEY partitioned
+        m_part_info->list_of_part_fields) ||
+       (m_is_sub_partitioned &&                       // KEY subpartitioned
+        m_part_info->list_of_subpart_fields)))
+  {
+    Field **field;
+    if (m_is_sub_partitioned)
+    {
+      field= m_part_info->subpart_field_array;
+    }
+    else
+    {
+      field= m_part_info->part_field_array;
+    }
+    for (; *field; field++)
+    {
+      switch ((*field)->real_type()) {
+      case MYSQL_TYPE_TINY:
+      case MYSQL_TYPE_SHORT:
+      case MYSQL_TYPE_LONG:
+      case MYSQL_TYPE_FLOAT:
+      case MYSQL_TYPE_DOUBLE:
+      case MYSQL_TYPE_NEWDECIMAL:
+      case MYSQL_TYPE_TIMESTAMP:
+      case MYSQL_TYPE_LONGLONG:
+      case MYSQL_TYPE_INT24:
+      case MYSQL_TYPE_TIME:
+      case MYSQL_TYPE_DATETIME:
+      case MYSQL_TYPE_YEAR:
+      case MYSQL_TYPE_NEWDATE:
+      case MYSQL_TYPE_ENUM:
+      case MYSQL_TYPE_SET:
+        {
+          THD *thd= ha_thd();
+          char *part_buf;
+          String db_name, table_name;
+          uint part_buf_len;
+          bool skip_generation= false;
+          partition_info::enum_key_algorithm old_algorithm;
+          old_algorithm= m_part_info->key_algorithm;
+          error= HA_ADMIN_FAILED;
+          append_identifier(ha_thd(), &db_name, &table_share->db);
+          append_identifier(ha_thd(), &table_name, &table_share->table_name);
+          if (m_part_info->key_algorithm != partition_info::KEY_ALGORITHM_NONE)
+          {
+            /*
+              Only possible when someone tampered with .frm files,
+              like during tests :)
+            */
+            skip_generation= true;
+          }
+          m_part_info->key_algorithm= partition_info::KEY_ALGORITHM_51;
+          if (skip_generation ||
+              !(part_buf= generate_partition_syntax_for_frm(thd, m_part_info,
+                                                            &part_buf_len,
+                                                            NULL, NULL)) ||
+	      print_admin_msg(thd, SQL_ADMIN_MSG_TEXT_SIZE + 1, "error",
+	                      table_share->db.str,
+	                      table->alias,
+                              opt_op_name[CHECK_PARTS],
+                              KEY_PARTITIONING_CHANGED_STR,
+                              db_name.c_ptr_safe(),
+                              table_name.c_ptr_safe(),
+                              part_buf))
+	  {
+	    /* Error creating admin message (too long string?). */
+	    print_admin_msg(thd, MYSQL_ERRMSG_SIZE, "error",
+                            table_share->db.str, table->alias,
+                            opt_op_name[CHECK_PARTS],
+                            KEY_PARTITIONING_CHANGED_STR,
+                            db_name.c_ptr_safe(), table_name.c_ptr_safe(),
+                            "<old partition clause>, but add ALGORITHM = 1"
+                            " between 'KEY' and '(' to change the metadata"
+                            " without the need of a full table rebuild.");
+          }
+          m_part_info->key_algorithm= old_algorithm;
+          DBUG_RETURN(error);
+        }
+      default:
+        /* Not affected! */
+        ;
+      }
+    }
+  }
+
+  DBUG_RETURN(error);
+}
+
+
+TABLE_LIST *ha_partition::get_next_global_for_child()
+{
+  handler **file;
+  DBUG_ENTER("ha_partition::get_next_global_for_child");
+  for (file= m_file; *file; file++)
+  {
+    TABLE_LIST *table_list;
+    if ((table_list= (*file)->get_next_global_for_child()))
+      DBUG_RETURN(table_list);
+  }
+  DBUG_RETURN(0);
+}
+
+
+/**
+  Push an engine condition to the condition stack of the storage engine
+  for each partition.
+
+  @param  cond              Pointer to the engine condition to be pushed.
+
+  @return NULL              Underlying engine will not return rows that
+                            do not match the passed condition.
+          <> NULL           'Remainder' condition that the caller must use
+                            to filter out records.
+*/
+
+const COND *ha_partition::cond_push(const COND *cond)
+{
+  uint i;
+  COND *res_cond= NULL;
+  DBUG_ENTER("ha_partition::cond_push");
+
+  for (i= bitmap_get_first_set(&m_partitions_to_reset);
+       i < m_tot_parts;
+       i= bitmap_get_next_set(&m_partitions_to_reset, i))
+  {
+    if (bitmap_is_set(&m_opened_partitions, i))
+    {
+      if (m_file[i]->pushed_cond != cond)
+      {
+        if (m_file[i]->cond_push(cond))
+          res_cond= (COND *) cond;
+        else
+          m_file[i]->pushed_cond= cond;
+      }
+    }
+  }
+  DBUG_RETURN(res_cond);
+}
+
+
+/**
+  Pop the top condition from the condition stack of the storage engine
+  for each partition.
+*/
+
+void ha_partition::cond_pop()
+{
+  uint i;
+  DBUG_ENTER("ha_partition::cond_pop");
+
+  for (i= bitmap_get_first_set(&m_partitions_to_reset);
+       i < m_tot_parts;
+       i= bitmap_get_next_set(&m_partitions_to_reset, i))
+  {
+    if (bitmap_is_set(&m_opened_partitions, i))
+    {
+      m_file[i]->cond_pop();
+    }
+  }
+  DBUG_VOID_RETURN;
+}
+
+
+/**
+  Perform bulk update preparation on each partition.
+
+  SYNOPSIS
+    start_bulk_update()
+
+  RETURN VALUE
+    TRUE                      Error
+    FALSE                     Success
+*/
+
+bool ha_partition::start_bulk_update()
+{
+  handler **file= m_file;
+  DBUG_ENTER("ha_partition::start_bulk_update");
+
+  if (bitmap_is_overlapping(&m_part_info->full_part_field_set,
+                            table->write_set))
+    DBUG_RETURN(TRUE);
+
+  do
+  {
+    bzero(&(*file)->copy_info, sizeof((*file)->copy_info));
+    if ((*file)->start_bulk_update())
+      DBUG_RETURN(TRUE);
+  } while (*(++file));
+  DBUG_RETURN(FALSE);
+}
+
+
+/**
+  Perform bulk update execution on each partition.  A bulk update allows
+  a handler to batch the updated rows instead of performing the updates
+  one row at a time.
+
+  SYNOPSIS
+    exec_bulk_update()
+
+  RETURN VALUE
+    TRUE                      Error
+    FALSE                     Success
+*/
+
+int ha_partition::exec_bulk_update(ha_rows *dup_key_found)
+{
+  int error;
+  handler **file= m_file;
+  DBUG_ENTER("ha_partition::exec_bulk_update");
+
+  do
+  {
+    if (unlikely((error= (*file)->exec_bulk_update(dup_key_found))))
+      DBUG_RETURN(error);
+  } while (*(++file));
+  DBUG_RETURN(0);
+}
+
+
+/**
+  Perform bulk update cleanup on each partition.
+
+  SYNOPSIS
+    end_bulk_update()
+
+  RETURN VALUE
+    NONE
+*/
+
+int ha_partition::end_bulk_update()
+{
+  int error= 0;
+  handler **file= m_file;
+  DBUG_ENTER("ha_partition::end_bulk_update");
+
+  do
+  {
+    int tmp;
+    if ((tmp= (*file)->end_bulk_update()))
+      error= tmp;
+  } while (*(++file));
+  sum_copy_infos();
+  DBUG_RETURN(error);
+}
+
+
+/**
+  Add the row to the bulk update on the partition on which the row is stored.
+  A bulk update allows a handler to batch the updated rows instead of
+  performing the updates one row at a time.
+
+  SYNOPSIS
+    bulk_update_row()
+    old_data                  Old record
+    new_data                  New record
+    dup_key_found             Number of duplicate keys found
+
+  RETURN VALUE
+    >1                        Error
+    1                         Bulk update not used, normal operation used
+    0                         Bulk update used by handler
+*/
+
+int ha_partition::bulk_update_row(const uchar *old_data, const uchar *new_data,
+                                  ha_rows *dup_key_found)
+{
+  int error= 0;
+  uint32 part_id;
+  longlong func_value;
+  DBUG_ENTER("ha_partition::bulk_update_row");
+
+  MY_BITMAP *old_map= dbug_tmp_use_all_columns(table, &table->read_set);
+  error= m_part_info->get_partition_id(m_part_info, &part_id,
+                                       &func_value);
+  dbug_tmp_restore_column_map(&table->read_set, old_map);
+  if (unlikely(error))
+  {
+    m_part_info->err_value= func_value;
+    goto end;
+  }
+
+  error= m_file[part_id]->ha_bulk_update_row(old_data, new_data,
+                                             dup_key_found);
+
+end:
+  DBUG_RETURN(error);
+}
+
+
+/**
+  Perform bulk delete preparation on each partition.
+
+  SYNOPSIS
+    start_bulk_delete()
+
+  RETURN VALUE
+    TRUE                      Error
+    FALSE                     Success
+*/
+
+bool ha_partition::start_bulk_delete()
+{
+  handler **file= m_file;
+  DBUG_ENTER("ha_partition::start_bulk_delete");
+
+  do
+  {
+    if ((*file)->start_bulk_delete())
+      DBUG_RETURN(TRUE);
+  } while (*(++file));
+  DBUG_RETURN(FALSE);
+}
+
+
+/**
+  Perform bulk delete cleanup on each partition.
+
+  SYNOPSIS
+    end_bulk_delete()
+
+  RETURN VALUE
+    >0                        Error
+    0                         Success
+*/
+
+int ha_partition::end_bulk_delete()
+{
+  int error= 0;
+  handler **file= m_file;
+  DBUG_ENTER("ha_partition::end_bulk_delete");
+
+  do
+  {
+    int tmp;
+    if ((tmp= (*file)->end_bulk_delete()))
+      error= tmp;
+  } while (*(++file));
+  sum_copy_infos();
+  DBUG_RETURN(error);
+}
+
+
+bool ha_partition::check_if_updates_are_ignored(const char *op) const
+{
+  return (handler::check_if_updates_are_ignored(op) ||
+          ha_check_if_updates_are_ignored(table->in_use, partition_ht(), op));
+}
+
+/**
+  Perform initialization for a direct update request.
+
+  SYNOPSIS
+    direct_update_rows_init()
+    update fields             Pointer to the list of fields to update
+
+  RETURN VALUE
+    >0                        Error
+    0                         Success
+*/
+
+int ha_partition::direct_update_rows_init(List<Item> *update_fields)
+{
+  int error;
+  uint i, found;
+  handler *file;
+  DBUG_ENTER("ha_partition::direct_update_rows_init");
+
+  if (bitmap_is_overlapping(&m_part_info->full_part_field_set,
+                            table->write_set))
+  {
+    DBUG_PRINT("info", ("partition FALSE by updating part_key"));
+    DBUG_RETURN(HA_ERR_WRONG_COMMAND);
+  }
+
+  m_part_spec.start_part= 0;
+  m_part_spec.end_part= m_tot_parts - 1;
+  m_direct_update_part_spec= m_part_spec;
+
+  found= 0;
+  for (i= m_part_spec.start_part; i <= m_part_spec.end_part; i++)
+  {
+    if (bitmap_is_set(&(m_part_info->read_partitions), i) &&
+        bitmap_is_set(&(m_part_info->lock_partitions), i))
+    {
+      file= m_file[i];
+      if (unlikely((error= (m_pre_calling ?
+                            file->pre_direct_update_rows_init(update_fields) :
+                            file->direct_update_rows_init(update_fields)))))
+      {
+        DBUG_PRINT("info", ("partition FALSE by storage engine"));
+        DBUG_RETURN(error);
+      }
+      found++;
+    }
+  }
+
+  TABLE_LIST *table_list= table->pos_in_table_list;
+  if (found != 1 && table_list)
+  {
+    while (table_list->parent_l)
+      table_list= table_list->parent_l;
+    st_select_lex *select_lex= table_list->select_lex;
+    DBUG_PRINT("info", ("partition select_lex: %p", select_lex));
+    if (select_lex && select_lex->explicit_limit)
+    {
+      DBUG_PRINT("info", ("partition explicit_limit=TRUE"));
+      DBUG_PRINT("info", ("partition offset_limit: %p",
+                          select_lex->offset_limit));
+      DBUG_PRINT("info", ("partition select_limit: %p",
+                          select_lex->select_limit));
+      DBUG_PRINT("info", ("partition FALSE by select_lex"));
+      DBUG_RETURN(HA_ERR_WRONG_COMMAND);
+    }
+  }
+  DBUG_PRINT("info", ("partition OK"));
+  DBUG_RETURN(0);
+}
+
+
+/**
+  Do initialization for performing parallel direct update
+  for a handlersocket update request.
+
+  SYNOPSIS
+    pre_direct_update_rows_init()
+    update fields             Pointer to the list of fields to update
+
+  RETURN VALUE
+    >0                        Error
+    0                         Success
+*/
+
+int ha_partition::pre_direct_update_rows_init(List<Item> *update_fields)
+{
+  bool save_m_pre_calling;
+  int error;
+  DBUG_ENTER("ha_partition::pre_direct_update_rows_init");
+  save_m_pre_calling= m_pre_calling;
+  m_pre_calling= TRUE;
+  error= direct_update_rows_init(update_fields);
+  m_pre_calling= save_m_pre_calling;
+  DBUG_RETURN(error);
+}
+
+
+/**
+  Execute a direct update request.  A direct update request updates all
+  qualified rows in a single operation, rather than one row at a time.
+  The direct update operation is pushed down to each individual
+  partition.
+
+  SYNOPSIS
+    direct_update_rows()
+    update_rows               Number of updated rows
+
+  RETURN VALUE
+    >0                        Error
+    0                         Success
+*/
+
+int ha_partition::direct_update_rows(ha_rows *update_rows_result,
+                                     ha_rows *found_rows_result)
+{
+  int error;
+  bool rnd_seq= FALSE;
+  ha_rows update_rows= 0;
+  ha_rows found_rows= 0;
+  uint32 i;
+  DBUG_ENTER("ha_partition::direct_update_rows");
+
+  /* If first call to direct_update_rows with RND scan */
+  if ((m_pre_calling ? pre_inited : inited) == RND && m_scan_value == 1)
+  {
+    rnd_seq= TRUE;
+    m_scan_value= 2;
+  }
+
+  *update_rows_result= 0;
+  *found_rows_result= 0;
+  for (i= m_part_spec.start_part; i <= m_part_spec.end_part; i++)
+  {
+    handler *file= m_file[i];
+    if (bitmap_is_set(&(m_part_info->read_partitions), i) &&
+        bitmap_is_set(&(m_part_info->lock_partitions), i))
+    {
+      if (rnd_seq && (m_pre_calling ? file->pre_inited : file->inited) == NONE)
+      {
+        if (unlikely((error= (m_pre_calling ?
+                              file->ha_pre_rnd_init(TRUE) :
+                              file->ha_rnd_init(TRUE)))))
+          DBUG_RETURN(error);
+      }
+      if (unlikely((error= (m_pre_calling ?
+                            (file)->pre_direct_update_rows() :
+                            (file)->ha_direct_update_rows(&update_rows,
+                                                          &found_rows)))))
+      {
+        if (rnd_seq)
+        {
+          if (m_pre_calling)
+            file->ha_pre_rnd_end();
+          else
+            file->ha_rnd_end();
+        }
+        DBUG_RETURN(error);
+      }
+      *update_rows_result+= update_rows;
+      *found_rows_result+= found_rows;
+    }
+    if (rnd_seq)
+    {
+      if (unlikely((error= (m_pre_calling ?
+                            file->ha_pre_index_or_rnd_end() :
+                            file->ha_index_or_rnd_end()))))
+        DBUG_RETURN(error);
+    }
+  }
+  DBUG_RETURN(0);
+}
+
+
+/**
+  Start parallel execution of a direct update for a handlersocket update
+  request.  A direct update request updates all qualified rows in a single
+  operation, rather than one row at a time.  The direct update operation
+  is pushed down to each individual partition.
+
+  SYNOPSIS
+    pre_direct_update_rows()
+
+  RETURN VALUE
+    >0                        Error
+    0                         Success
+*/
+
+int ha_partition::pre_direct_update_rows()
+{
+  bool save_m_pre_calling;
+  int error;
+  ha_rows not_used= 0;
+  DBUG_ENTER("ha_partition::pre_direct_update_rows");
+  save_m_pre_calling= m_pre_calling;
+  m_pre_calling= TRUE;
+  error= direct_update_rows(&not_used, &not_used);
+  m_pre_calling= save_m_pre_calling;
+  DBUG_RETURN(error);
+}
+
+
+/**
+  Perform initialization for a direct delete request.
+
+  SYNOPSIS
+    direct_delete_rows_init()
+
+  RETURN VALUE
+    >0                        Error
+    0                         Success
+*/
+
+int ha_partition::direct_delete_rows_init()
+{
+  int error;
+  uint i, found;
+  DBUG_ENTER("ha_partition::direct_delete_rows_init");
+
+  m_part_spec.start_part= 0;
+  m_part_spec.end_part= m_tot_parts - 1;
+  m_direct_update_part_spec= m_part_spec;
+
+  found= 0;
+  for (i= m_part_spec.start_part; i <= m_part_spec.end_part; i++)
+  {
+    if (bitmap_is_set(&(m_part_info->read_partitions), i) &&
+        bitmap_is_set(&(m_part_info->lock_partitions), i))
+    {
+      handler *file= m_file[i];
+      if (unlikely((error= (m_pre_calling ?
+                            file->pre_direct_delete_rows_init() :
+                            file->direct_delete_rows_init()))))
+      {
+        DBUG_PRINT("exit", ("error in direct_delete_rows_init"));
+        DBUG_RETURN(error);
+      }
+      found++;
+    }
+  }
+
+  TABLE_LIST *table_list= table->pos_in_table_list;
+  if (found != 1 && table_list)
+  {
+    while (table_list->parent_l)
+      table_list= table_list->parent_l;
+    st_select_lex *select_lex= table_list->select_lex;
+    DBUG_PRINT("info", ("partition select_lex: %p", select_lex));
+    if (select_lex && select_lex->explicit_limit)
+    {
+      DBUG_PRINT("info", ("partition explicit_limit: TRUE"));
+      DBUG_PRINT("info", ("partition offset_limit: %p",
+                          select_lex->offset_limit));
+      DBUG_PRINT("info", ("partition select_limit: %p",
+                          select_lex->select_limit));
+      DBUG_PRINT("info", ("partition FALSE by select_lex"));
+      DBUG_RETURN(HA_ERR_WRONG_COMMAND);
+    }
+  }
+  DBUG_PRINT("exit", ("OK"));
+  DBUG_RETURN(0);
+}
+
+
+/**
+  Do initialization for performing parallel direct delete
+  for a handlersocket delete request.
+
+  SYNOPSIS
+    pre_direct_delete_rows_init()
+
+  RETURN VALUE
+    >0                        Error
+    0                         Success
+*/
+
+int ha_partition::pre_direct_delete_rows_init()
+{
+  bool save_m_pre_calling;
+  int error;
+  DBUG_ENTER("ha_partition::pre_direct_delete_rows_init");
+  save_m_pre_calling= m_pre_calling;
+  m_pre_calling= TRUE;
+  error= direct_delete_rows_init();
+  m_pre_calling= save_m_pre_calling;
+  DBUG_RETURN(error);
+}
+
+
+/**
+  Execute a direct delete request.  A direct delete request deletes all
+  qualified rows in a single operation, rather than one row at a time.
+  The direct delete operation is pushed down to each individual
+  partition.
+
+  SYNOPSIS
+    direct_delete_rows()
+    delete_rows               Number of deleted rows
+
+  RETURN VALUE
+    >0                        Error
+    0                         Success
+*/
+
+int ha_partition::direct_delete_rows(ha_rows *delete_rows_result)
+{
+  int error;
+  bool rnd_seq= FALSE;
+  ha_rows delete_rows= 0;
+  uint32 i;
+  handler *file;
+  DBUG_ENTER("ha_partition::direct_delete_rows");
+
+  if ((m_pre_calling ? pre_inited : inited) == RND && m_scan_value == 1)
+  {
+    rnd_seq= TRUE;
+    m_scan_value= 2;
+  }
+
+  *delete_rows_result= 0;
+  m_part_spec= m_direct_update_part_spec;
+  for (i= m_part_spec.start_part; i <= m_part_spec.end_part; i++)
+  {
+    file= m_file[i];
+    if (bitmap_is_set(&(m_part_info->read_partitions), i) &&
+        bitmap_is_set(&(m_part_info->lock_partitions), i))
+    {
+      if (rnd_seq && (m_pre_calling ? file->pre_inited : file->inited) == NONE)
+      {
+        if (unlikely((error= (m_pre_calling ?
+                              file->ha_pre_rnd_init(TRUE) :
+                              file->ha_rnd_init(TRUE)))))
+          DBUG_RETURN(error);
+      }
+      if ((error= (m_pre_calling ?
+                   file->pre_direct_delete_rows() :
+                   file->ha_direct_delete_rows(&delete_rows))))
+      {
+        if (m_pre_calling)
+          file->ha_pre_rnd_end();
+        else
+          file->ha_rnd_end();
+        DBUG_RETURN(error);
+      }
+      delete_rows_result+= delete_rows;
+    }
+    if (rnd_seq)
+    {
+      if (unlikely((error= (m_pre_calling ?
+                            file->ha_pre_index_or_rnd_end() :
+                            file->ha_index_or_rnd_end()))))
+        DBUG_RETURN(error);
+    }
+  }
+  DBUG_RETURN(0);
+}
+
+
+/**
+  Start parallel execution of a direct delete for a handlersocket delete
+  request.  A direct delete request deletes all qualified rows in a single
+  operation, rather than one row at a time.  The direct delete operation
+  is pushed down to each individual partition.
+
+  SYNOPSIS
+    pre_direct_delete_rows()
+
+  RETURN VALUE
+    >0                        Error
+    0                         Success
+*/
+
+int ha_partition::pre_direct_delete_rows()
+{
+  bool save_m_pre_calling;
+  int error;
+  ha_rows not_used;
+  DBUG_ENTER("ha_partition::pre_direct_delete_rows");
+  save_m_pre_calling= m_pre_calling;
+  m_pre_calling= TRUE;
+  error= direct_delete_rows(&not_used);
+  m_pre_calling= save_m_pre_calling;
+  DBUG_RETURN(error);
+}
+
+/**
+  Push metadata for the current operation down to each partition.
+
+  SYNOPSIS
+    info_push()
+
+  RETURN VALUE
+    >0                        Error
+    0                         Success
+*/
+
+int ha_partition::info_push(uint info_type, void *info)
+{
+  int error= 0, tmp;
+  uint i;
+  DBUG_ENTER("ha_partition::info_push");
+
+  for (i= bitmap_get_first_set(&m_partitions_to_reset);
+       i < m_tot_parts;
+       i= bitmap_get_next_set(&m_partitions_to_reset, i))
+  {
+    if (bitmap_is_set(&m_opened_partitions, i))
+    {
+      if ((tmp= m_file[i]->info_push(info_type, info)))
+      {
+        error= tmp;
+      }
+    }
+  }
+  DBUG_RETURN(error);
+}
+
+
+bool
+ha_partition::can_convert_string(const Field_string* field,
+		                 const Column_definition& new_type) const
+{
+  for (uint index= 0; index < m_tot_parts; index++)
+  {
+    if (!m_file[index]->can_convert_string(field, new_type))
+      return false;
+  }
+  return true;
+}
+
+bool
+ha_partition::can_convert_varstring(const Field_varstring* field,
+		                    const Column_definition& new_type) const{
+  for (uint index= 0; index < m_tot_parts; index++)
+  {
+    if (!m_file[index]->can_convert_varstring(field, new_type))
+      return false;
+  }
+  return true;
+}
+
+bool
+ha_partition::can_convert_blob(const Field_blob* field,
+		               const Column_definition& new_type) const
+{
+  for (uint index= 0; index < m_tot_parts; index++)
+  {
+    if (!m_file[index]->can_convert_blob(field, new_type))
+      return false;
+  }
+  return true;
+}
+
+struct st_mysql_storage_engine partition_storage_engine=
+{ MYSQL_HANDLERTON_INTERFACE_VERSION };
+
+maria_declare_plugin(partition)
+{
+  MYSQL_STORAGE_ENGINE_PLUGIN,
+  &partition_storage_engine,
+  "partition",
+  "Mikael Ronstrom, MySQL AB",
+  "Partition Storage Engine Helper",
+  PLUGIN_LICENSE_GPL,
+  partition_initialize, /* Plugin Init */
+  NULL, /* Plugin Deinit */
+  0x0100, /* 1.0 */
+  NULL,                       /* status variables                */
+  NULL,                       /* system variables                */
+  "1.0",                      /* string version                  */
+  MariaDB_PLUGIN_MATURITY_STABLE /* maturity                     */
+}
+maria_declare_plugin_end;
+
+#endif