summaryrefslogtreecommitdiffstats
path: root/sql/sql_base.cc
diff options
context:
space:
mode:
authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-04 18:07:14 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-04 18:07:14 +0000
commita175314c3e5827eb193872241446f2f8f5c9d33c (patch)
treecd3d60ca99ae00829c52a6ca79150a5b6e62528b /sql/sql_base.cc
parentInitial commit. (diff)
downloadmariadb-10.5-upstream.tar.xz
mariadb-10.5-upstream.zip
Adding upstream version 1:10.5.12.upstream/1%10.5.12upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r--sql/sql_base.cc9239
1 files changed, 9239 insertions, 0 deletions
diff --git a/sql/sql_base.cc b/sql/sql_base.cc
new file mode 100644
index 00000000..a9d7de9a
--- /dev/null
+++ b/sql/sql_base.cc
@@ -0,0 +1,9239 @@
+/* Copyright (c) 2000, 2016, Oracle and/or its affiliates.
+ Copyright (c) 2010, 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 Street, Fifth Floor, Boston, MA 02110-1335 USA */
+
+
+/* Basic functions needed by many modules */
+
+#include "mariadb.h"
+#include "sql_base.h" // setup_table_map
+#include "sql_priv.h"
+#include "unireg.h"
+#include "debug_sync.h"
+#include "lock.h" // mysql_lock_remove,
+ // mysql_unlock_tables,
+ // mysql_lock_have_duplicate
+#include "sql_show.h" // append_identifier
+#include "strfunc.h" // find_type
+#include "sql_view.h" // mysql_make_view, VIEW_ANY_ACL
+#include "sql_parse.h" // check_table_access
+#include "sql_insert.h" // kill_delayed_threads
+#include "sql_partition.h" // ALTER_PARTITION_PARAM_TYPE
+#include "sql_derived.h" // mysql_derived_prepare,
+ // mysql_handle_derived,
+ // mysql_derived_filling
+#include "sql_handler.h" // mysql_ha_flush
+#include "sql_test.h"
+#include "sql_partition.h" // ALTER_PARTITION_PARAM_TYPE
+#include "log_event.h" // Query_log_event
+#include "sql_select.h"
+#include "sp_head.h"
+#include "sp.h"
+#include "sp_cache.h"
+#include "sql_trigger.h"
+#include "transaction.h"
+#include "sql_prepare.h"
+#include "sql_statistics.h"
+#include "sql_cte.h"
+#include <m_ctype.h>
+#include <my_dir.h>
+#include <hash.h>
+#include "rpl_filter.h"
+#include "sql_table.h" // build_table_filename
+#include "datadict.h" // dd_frm_is_view()
+#include "rpl_rli.h" // rpl_group_info
+#ifdef __WIN__
+#include <io.h>
+#endif
+#include "wsrep_mysqld.h"
+#ifdef WITH_WSREP
+#include "wsrep_thd.h"
+#include "wsrep_trans_observer.h"
+#endif /* WITH_WSREP */
+
+
+bool
+No_such_table_error_handler::handle_condition(THD *,
+ uint sql_errno,
+ const char*,
+ Sql_condition::enum_warning_level *level,
+ const char*,
+ Sql_condition ** cond_hdl)
+{
+ *cond_hdl= NULL;
+ if (sql_errno == ER_NO_SUCH_TABLE || sql_errno == ER_NO_SUCH_TABLE_IN_ENGINE)
+ {
+ m_handled_errors++;
+ return TRUE;
+ }
+
+ if (*level == Sql_condition::WARN_LEVEL_ERROR)
+ m_unhandled_errors++;
+ return FALSE;
+}
+
+
+bool No_such_table_error_handler::safely_trapped_errors()
+{
+ /*
+ If m_unhandled_errors != 0, something else, unanticipated, happened,
+ so the error is not trapped but returned to the caller.
+ Multiple ER_NO_SUCH_TABLE can be raised in case of views.
+ */
+ return ((m_handled_errors > 0) && (m_unhandled_errors == 0));
+}
+
+
+/**
+ This internal handler is used to trap ER_NO_SUCH_TABLE and
+ ER_WRONG_MRG_TABLE errors during CHECK/REPAIR TABLE for MERGE
+ tables.
+*/
+
+class Repair_mrg_table_error_handler : public Internal_error_handler
+{
+public:
+ Repair_mrg_table_error_handler()
+ : m_handled_errors(false), m_unhandled_errors(false)
+ {}
+
+ bool handle_condition(THD *thd,
+ uint sql_errno,
+ const char* sqlstate,
+ Sql_condition::enum_warning_level *level,
+ const char* msg,
+ Sql_condition ** cond_hdl);
+
+ /**
+ Returns TRUE if there were ER_NO_SUCH_/WRONG_MRG_TABLE and there
+ were no unhandled errors. FALSE otherwise.
+ */
+ bool safely_trapped_errors()
+ {
+ /*
+ Check for m_handled_errors is here for extra safety.
+ It can be useful in situation when call to open_table()
+ fails because some error which was suppressed by another
+ error handler (e.g. in case of MDL deadlock which we
+ decided to solve by back-off and retry).
+ */
+ return (m_handled_errors && (! m_unhandled_errors));
+ }
+
+private:
+ bool m_handled_errors;
+ bool m_unhandled_errors;
+};
+
+
+bool
+Repair_mrg_table_error_handler::handle_condition(THD *,
+ uint sql_errno,
+ const char*,
+ Sql_condition::enum_warning_level *level,
+ const char*,
+ Sql_condition ** cond_hdl)
+{
+ *cond_hdl= NULL;
+ if (sql_errno == ER_NO_SUCH_TABLE ||
+ sql_errno == ER_NO_SUCH_TABLE_IN_ENGINE ||
+ sql_errno == ER_WRONG_MRG_TABLE)
+ {
+ m_handled_errors= true;
+ return TRUE;
+ }
+
+ m_unhandled_errors= true;
+ return FALSE;
+}
+
+
+/**
+ @defgroup Data_Dictionary Data Dictionary
+ @{
+*/
+
+static bool check_and_update_table_version(THD *thd, TABLE_LIST *tables,
+ TABLE_SHARE *table_share);
+static bool open_table_entry_fini(THD *thd, TABLE_SHARE *share, TABLE *entry);
+static bool auto_repair_table(THD *thd, TABLE_LIST *table_list);
+
+
+/**
+ Get table cache key for a table list element.
+
+ @param table_list[in] Table list element.
+ @param key[out] On return points to table cache key for the table.
+
+ @note Unlike create_table_def_key() call this function doesn't construct
+ key in a buffer provided by caller. Instead it relies on the fact
+ that table list element for which key is requested has properly
+ initialized MDL_request object and the fact that table definition
+ cache key is suffix of key used in MDL subsystem. So to get table
+ definition key it simply needs to return pointer to appropriate
+ part of MDL_key object nested in this table list element.
+ Indeed, this means that lifetime of key produced by this call is
+ limited by the lifetime of table list element which it got as
+ parameter.
+
+ @return Length of key.
+*/
+
+uint get_table_def_key(const TABLE_LIST *table_list, const char **key)
+{
+ /*
+ This call relies on the fact that TABLE_LIST::mdl_request::key object
+ is properly initialized, so table definition cache can be produced
+ from key used by MDL subsystem.
+ */
+ DBUG_ASSERT(!strcmp(table_list->get_db_name(),
+ table_list->mdl_request.key.db_name()));
+ DBUG_ASSERT(!strcmp(table_list->get_table_name(),
+ table_list->mdl_request.key.name()));
+
+ *key= (const char*)table_list->mdl_request.key.ptr() + 1;
+ return table_list->mdl_request.key.length() - 1;
+}
+
+
+
+/*****************************************************************************
+ Functions to handle table definition cache (TABLE_SHARE)
+*****************************************************************************/
+
+/*
+ Create a list for all open tables matching SQL expression
+
+ SYNOPSIS
+ list_open_tables()
+ thd Thread THD
+ wild SQL like expression
+
+ NOTES
+ One gets only a list of tables for which one has any kind of privilege.
+ db and table names are allocated in result struct, so one doesn't need
+ a lock when traversing the return list.
+
+ RETURN VALUES
+ NULL Error (Probably OOM)
+ # Pointer to list of names of open tables.
+*/
+
+struct list_open_tables_arg
+{
+ THD *thd;
+ const char *db;
+ const char *wild;
+ TABLE_LIST table_list;
+ OPEN_TABLE_LIST **start_list, *open_list;
+};
+
+
+static my_bool list_open_tables_callback(TDC_element *element,
+ list_open_tables_arg *arg)
+{
+ const char *db= (char*) element->m_key;
+ size_t db_length= strlen(db);
+ const char *table_name= db + db_length + 1;
+
+ if (arg->db && my_strcasecmp(system_charset_info, arg->db, db))
+ return FALSE;
+ if (arg->wild && wild_compare(table_name, arg->wild, 0))
+ return FALSE;
+
+ /* Check if user has SELECT privilege for any column in the table */
+ arg->table_list.db.str= db;
+ arg->table_list.db.length= db_length;
+ arg->table_list.table_name.str= table_name;
+ arg->table_list.table_name.length= strlen(table_name);
+ arg->table_list.grant.privilege= NO_ACL;
+
+ if (check_table_access(arg->thd, SELECT_ACL, &arg->table_list, TRUE, 1, TRUE))
+ return FALSE;
+
+ if (!(*arg->start_list= (OPEN_TABLE_LIST *) arg->thd->alloc(
+ sizeof(**arg->start_list) + element->m_key_length)))
+ return TRUE;
+
+ strmov((*arg->start_list)->table=
+ strmov(((*arg->start_list)->db= (char*) ((*arg->start_list) + 1)),
+ db) + 1, table_name);
+ (*arg->start_list)->in_use= 0;
+
+ mysql_mutex_lock(&element->LOCK_table_share);
+ All_share_tables_list::Iterator it(element->all_tables);
+ TABLE *table;
+ while ((table= it++))
+ if (table->in_use)
+ ++(*arg->start_list)->in_use;
+ mysql_mutex_unlock(&element->LOCK_table_share);
+ (*arg->start_list)->locked= 0; /* Obsolete. */
+ arg->start_list= &(*arg->start_list)->next;
+ *arg->start_list= 0;
+ return FALSE;
+}
+
+
+OPEN_TABLE_LIST *list_open_tables(THD *thd, const char *db, const char *wild)
+{
+ list_open_tables_arg argument;
+ DBUG_ENTER("list_open_tables");
+
+ argument.thd= thd;
+ argument.db= db;
+ argument.wild= wild;
+ bzero((char*) &argument.table_list, sizeof(argument.table_list));
+ argument.start_list= &argument.open_list;
+ argument.open_list= 0;
+
+ if (tdc_iterate(thd, (my_hash_walk_action) list_open_tables_callback,
+ &argument, true))
+ DBUG_RETURN(0);
+
+ DBUG_RETURN(argument.open_list);
+}
+
+
+/**
+ Close all tables that are not in use in table definition cache
+*/
+
+void purge_tables()
+{
+ /*
+ Force close of all open tables.
+
+ Note that code in TABLE_SHARE::wait_for_old_version() assumes that
+ incrementing of refresh_version is followed by purge of unused table
+ shares.
+ */
+ kill_delayed_threads();
+ /*
+ Get rid of all unused TABLE and TABLE_SHARE instances. By doing
+ this we automatically close all tables which were marked as "old".
+ */
+ tc_purge();
+ /* Free table shares which were not freed implicitly by loop above. */
+ tdc_purge(true);
+}
+
+
+/**
+ close_cached_tables
+
+ This function has two separate usages:
+ 1) Close not used tables in the table cache to free memory
+ 2) Close a list of tables and wait until they are not used anymore. This
+ is used mainly when preparing a table for export.
+
+ If there are locked tables, they are closed and reopened before
+ function returns. This is done to ensure that table files will be closed
+ by all threads and thus external copyable when FLUSH TABLES returns.
+*/
+
+bool close_cached_tables(THD *thd, TABLE_LIST *tables,
+ bool wait_for_refresh, ulong timeout)
+{
+ DBUG_ENTER("close_cached_tables");
+ DBUG_ASSERT(thd || (!wait_for_refresh && !tables));
+ DBUG_ASSERT(wait_for_refresh || !tables);
+
+ if (!tables)
+ {
+ /* Free tables that are not used */
+ purge_tables();
+ if (!wait_for_refresh)
+ DBUG_RETURN(false);
+ }
+
+ DBUG_PRINT("info", ("open table definitions: %d",
+ (int) tdc_records()));
+
+ if (thd->locked_tables_mode)
+ {
+ /*
+ If we are under LOCK TABLES, we need to reopen the tables without
+ opening a door for any concurrent threads to sneak in and get
+ lock on our tables. To achieve this we use exclusive metadata
+ locks.
+ */
+ TABLE_LIST *tables_to_reopen= (tables ? tables :
+ thd->locked_tables_list.locked_tables());
+ bool result= false;
+
+ /* close open HANDLER for this thread to allow table to be closed */
+ mysql_ha_flush_tables(thd, tables_to_reopen);
+
+ for (TABLE_LIST *table_list= tables_to_reopen; table_list;
+ table_list= table_list->next_global)
+ {
+ int err;
+ /* A check that the table was locked for write is done by the caller. */
+ TABLE *table= find_table_for_mdl_upgrade(thd, table_list->db.str,
+ table_list->table_name.str, &err);
+
+ /* May return NULL if this table has already been closed via an alias. */
+ if (! table)
+ continue;
+
+ if (wait_while_table_is_used(thd, table,
+ HA_EXTRA_PREPARE_FOR_FORCED_CLOSE))
+ {
+ result= true;
+ break;
+ }
+ close_all_tables_for_name(thd, table->s, HA_EXTRA_NOT_USED, NULL);
+ }
+ /*
+ No other thread has the locked tables open; reopen them and get the
+ old locks. This should always succeed (unless some external process
+ has removed the tables)
+ */
+ if (thd->locked_tables_list.reopen_tables(thd, false))
+ result= true;
+
+ /*
+ Since downgrade_lock() won't do anything with shared
+ metadata lock it is much simpler to go through all open tables rather
+ than picking only those tables that were flushed.
+ */
+ for (TABLE *tab= thd->open_tables; tab; tab= tab->next)
+ tab->mdl_ticket->downgrade_lock(MDL_SHARED_NO_READ_WRITE);
+
+ DBUG_RETURN(result);
+ }
+ else if (tables)
+ {
+ /*
+ Get an explicit MDL lock for all requested tables to ensure they are
+ not used by any other thread
+ */
+ MDL_request_list mdl_requests;
+
+ DBUG_PRINT("info", ("Waiting for other threads to close their open tables"));
+ DEBUG_SYNC(thd, "after_flush_unlock");
+
+ /* close open HANDLER for this thread to allow table to be closed */
+ mysql_ha_flush_tables(thd, tables);
+
+ for (TABLE_LIST *table= tables; table; table= table->next_local)
+ {
+ MDL_request *mdl_request= new (thd->mem_root) MDL_request;
+ if (mdl_request == NULL)
+ DBUG_RETURN(true);
+ MDL_REQUEST_INIT_BY_KEY(mdl_request, &table->mdl_request.key,
+ MDL_EXCLUSIVE, MDL_STATEMENT);
+ mdl_requests.push_front(mdl_request);
+ }
+
+ if (thd->mdl_context.acquire_locks(&mdl_requests, timeout))
+ DBUG_RETURN(true);
+
+ for (TABLE_LIST *table= tables; table; table= table->next_local)
+ tdc_remove_table(thd, table->db.str, table->table_name.str);
+ }
+ DBUG_RETURN(false);
+}
+
+
+/**
+ Collect all shares that has open tables
+*/
+
+struct tc_collect_arg
+{
+ DYNAMIC_ARRAY shares;
+ flush_tables_type flush_type;
+};
+
+static my_bool tc_collect_used_shares(TDC_element *element,
+ tc_collect_arg *arg)
+{
+ my_bool result= FALSE;
+
+ DYNAMIC_ARRAY *shares= &arg->shares;
+ mysql_mutex_lock(&element->LOCK_table_share);
+ if (element->ref_count > 0 && !element->share->is_view)
+ {
+ DBUG_ASSERT(element->share);
+ bool do_flush= 0;
+ switch (arg->flush_type) {
+ case FLUSH_ALL:
+ do_flush= 1;
+ break;
+ case FLUSH_NON_TRANS_TABLES:
+ if (!element->share->online_backup &&
+ element->share->table_category == TABLE_CATEGORY_USER)
+ do_flush= 1;
+ break;
+ case FLUSH_SYS_TABLES:
+ if (!element->share->online_backup &&
+ element->share->table_category != TABLE_CATEGORY_USER)
+ do_flush= 1;
+ }
+ if (do_flush)
+ {
+ element->ref_count++; // Protect against delete
+ if (push_dynamic(shares, (uchar*) &element->share))
+ result= TRUE;
+ }
+ }
+ mysql_mutex_unlock(&element->LOCK_table_share);
+ return result;
+}
+
+
+/*
+ Ignore errors from opening read only tables
+*/
+
+class flush_tables_error_handler : public Internal_error_handler
+{
+public:
+ int handled_errors;
+ int unhandled_errors;
+ flush_tables_error_handler() : handled_errors(0), unhandled_errors(0)
+ {}
+
+ bool handle_condition(THD *thd,
+ uint sql_errno,
+ const char* sqlstate,
+ Sql_condition::enum_warning_level *level,
+ const char* msg,
+ Sql_condition ** cond_hdl)
+ {
+ *cond_hdl= NULL;
+ if (sql_errno == ER_OPEN_AS_READONLY)
+ {
+ handled_errors++;
+ return TRUE;
+ }
+ if (*level == Sql_condition::WARN_LEVEL_ERROR)
+ unhandled_errors++;
+ return FALSE;
+ }
+
+ bool got_fatal_error()
+ {
+ return unhandled_errors > 0;
+ }
+};
+
+
+/**
+ Flush cached table as part of global read lock
+
+ @param thd
+ @param flag What type of tables should be flushed
+
+ @return 0 ok
+ @return 1 error
+
+ After we get the list of table shares, we will call flush on all
+ possible tables, even if some flush fails.
+*/
+
+bool flush_tables(THD *thd, flush_tables_type flag)
+{
+ bool result= TRUE;
+ tc_collect_arg collect_arg;
+ TABLE *tmp_table;
+ flush_tables_error_handler error_handler;
+ DBUG_ENTER("flush_tables");
+
+ purge_tables(); /* Flush unused tables and shares */
+
+ /*
+ Loop over all shares and collect shares that have open tables
+ TODO:
+ Optimize this to only collect shares that have been used for
+ write after last time all tables was closed.
+ */
+
+ if (!(tmp_table= (TABLE*) my_malloc(PSI_INSTRUMENT_ME, sizeof(*tmp_table),
+ MYF(MY_WME | MY_THREAD_SPECIFIC))))
+ DBUG_RETURN(1);
+
+ my_init_dynamic_array(PSI_INSTRUMENT_ME, &collect_arg.shares,
+ sizeof(TABLE_SHARE*), 100, 100, MYF(0));
+ collect_arg.flush_type= flag;
+ if (tdc_iterate(thd, (my_hash_walk_action) tc_collect_used_shares,
+ &collect_arg, true))
+ {
+ /* Release already collected shares */
+ for (uint i= 0 ; i < collect_arg.shares.elements ; i++)
+ {
+ TABLE_SHARE *share= *dynamic_element(&collect_arg.shares, i,
+ TABLE_SHARE**);
+ tdc_release_share(share);
+ }
+ goto err;
+ }
+
+ /* Call HA_EXTRA_FLUSH on all found shares */
+
+ thd->push_internal_handler(&error_handler);
+ for (uint i= 0 ; i < collect_arg.shares.elements ; i++)
+ {
+ TABLE_SHARE *share= *dynamic_element(&collect_arg.shares, i,
+ TABLE_SHARE**);
+ TABLE *table= tc_acquire_table(thd, share->tdc);
+ if (table)
+ {
+ (void) table->file->extra(HA_EXTRA_FLUSH);
+ tc_release_table(table);
+ }
+ else
+ {
+ /*
+ HA_OPEN_FOR_FLUSH is used to allow us to open the table even if
+ TABLE_SHARE::incompatible_version is set. It also will tell
+ SEQUENCE engine that we don't have to read the sequence information
+ (which may cause deadlocks with concurrently running ALTER TABLE or
+ ALTER SEQUENCE) as we will close the table at once.
+ */
+ if (!open_table_from_share(thd, share, &empty_clex_str,
+ HA_OPEN_KEYFILE, 0,
+ HA_OPEN_FOR_ALTER | HA_OPEN_FOR_FLUSH,
+ tmp_table, FALSE,
+ NULL))
+ {
+ (void) tmp_table->file->extra(HA_EXTRA_FLUSH);
+ /*
+ We don't put the table into the TDC as the table was not fully
+ opened (we didn't open triggers)
+ */
+ closefrm(tmp_table);
+ }
+ }
+ tdc_release_share(share);
+ }
+ thd->pop_internal_handler();
+ result= error_handler.got_fatal_error();
+ DBUG_PRINT("note", ("open_errors: %u %u",
+ error_handler.handled_errors,
+ error_handler.unhandled_errors));
+err:
+ my_free(tmp_table);
+ delete_dynamic(&collect_arg.shares);
+ DBUG_RETURN(result);
+}
+
+
+/*
+ Mark all tables in the list which were used by current substatement
+ as free for reuse.
+
+ SYNOPSIS
+ mark_used_tables_as_free_for_reuse()
+ thd - thread context
+ table - head of the list of tables
+
+ DESCRIPTION
+ Marks all tables in the list which were used by current substatement
+ (they are marked by its query_id) as free for reuse.
+
+ Clear 'check_table_binlog_row_based_done' flag. For tables which were used
+ by current substatement the flag is cleared as part of 'ha_reset()' call.
+ For the rest of the open tables not used by current substament if this
+ flag is enabled as part of current substatement execution,
+ (for example when THD::binlog_write_table_maps() calls
+ prepare_for_row_logging()), clear the flag explicitly.
+
+ NOTE
+ The reason we reset query_id is that it's not enough to just test
+ if table->query_id != thd->query_id to know if a table is in use.
+
+ For example
+ SELECT f1_that_uses_t1() FROM t1;
+ In f1_that_uses_t1() we will see one instance of t1 where query_id is
+ set to query_id of original query.
+*/
+
+static void mark_used_tables_as_free_for_reuse(THD *thd, TABLE *table)
+{
+ DBUG_ENTER("mark_used_tables_as_free_for_reuse");
+ for (; table ; table= table->next)
+ {
+ DBUG_ASSERT(table->pos_in_locked_tables == NULL ||
+ table->pos_in_locked_tables->table == table);
+ if (table->query_id == thd->query_id)
+ {
+ table->query_id= 0;
+ table->file->ha_reset();
+ }
+ else
+ table->file->clear_cached_table_binlog_row_based_flag();
+ }
+ DBUG_VOID_RETURN;
+}
+
+
+/**
+ Close all open instances of the table but keep the MDL lock.
+
+ Works both under LOCK TABLES and in the normal mode.
+ Removes all closed instances of the table from the table cache.
+
+ @param thd thread handle
+ @param[in] share table share, but is just a handy way to
+ access the table cache key
+
+ @param[in] extra
+ HA_EXTRA_PREPARE_FOR_DROP
+ - The table is dropped
+ HA_EXTRA_PREPARE_FOR_RENAME
+ - The table is renamed
+ HA_EXTRA_NOT_USED
+ - The table is marked as closed in the
+ locked_table_list but kept there so one can call
+ locked_table_list->reopen_tables() to put it back.
+
+ In case of drop/rename the documented behavior is to
+ implicitly remove the table from LOCK TABLES
+ list.
+
+ @pre Must be called with an X MDL lock on the table.
+*/
+
+void
+close_all_tables_for_name(THD *thd, TABLE_SHARE *share,
+ ha_extra_function extra,
+ TABLE *skip_table)
+{
+ DBUG_ASSERT(!share->tmp_table);
+ DBUG_ASSERT(share->tdc->flushed);
+
+ char key[MAX_DBKEY_LENGTH];
+ size_t key_length= share->table_cache_key.length;
+ bool remove_from_locked_tables= extra != HA_EXTRA_NOT_USED;
+
+ memcpy(key, share->table_cache_key.str, key_length);
+
+ for (TABLE **prev= &thd->open_tables; *prev; )
+ {
+ TABLE *table= *prev;
+
+ if (table->s->table_cache_key.length == key_length &&
+ !memcmp(table->s->table_cache_key.str, key, key_length) &&
+ table != skip_table)
+ {
+ thd->locked_tables_list.unlink_from_list(thd,
+ table->pos_in_locked_tables,
+ remove_from_locked_tables);
+ /* Inform handler that there is a drop table or a rename going on */
+ if (extra != HA_EXTRA_NOT_USED && table->db_stat)
+ {
+ table->file->extra(extra);
+ extra= HA_EXTRA_NOT_USED; // Call extra once!
+ }
+
+ /*
+ Does nothing if the table is not locked.
+ This allows one to use this function after a table
+ has been unlocked, e.g. in partition management.
+ */
+ mysql_lock_remove(thd, thd->lock, table);
+ close_thread_table(thd, prev);
+ }
+ else
+ {
+ /* Step to next entry in open_tables list. */
+ prev= &table->next;
+ }
+ }
+}
+
+
+/*
+ Close all tables used by the current substatement, or all tables
+ used by this thread if we are on the upper level.
+
+ SYNOPSIS
+ close_thread_tables()
+ thd Thread handler
+
+ IMPLEMENTATION
+ Unlocks tables and frees derived tables.
+ Put all normal tables used by thread in free list.
+
+ It will only close/mark as free for reuse tables opened by this
+ substatement, it will also check if we are closing tables after
+ execution of complete query (i.e. we are on upper level) and will
+ leave prelocked mode if needed.
+*/
+
+int close_thread_tables(THD *thd)
+{
+ TABLE *table;
+ int error= 0;
+ DBUG_ENTER("close_thread_tables");
+
+ THD_STAGE_INFO(thd, stage_closing_tables);
+
+#ifdef EXTRA_DEBUG
+ DBUG_PRINT("tcache", ("open tables:"));
+ for (table= thd->open_tables; table; table= table->next)
+ DBUG_PRINT("tcache", ("table: '%s'.'%s' %p", table->s->db.str,
+ table->s->table_name.str, table));
+#endif
+
+#if defined(ENABLED_DEBUG_SYNC)
+ /* debug_sync may not be initialized for some slave threads */
+ if (thd->debug_sync_control)
+ DEBUG_SYNC(thd, "before_close_thread_tables");
+#endif
+
+ DBUG_ASSERT(thd->transaction->stmt.is_empty() || thd->in_sub_stmt ||
+ (thd->state_flags & Open_tables_state::BACKUPS_AVAIL));
+
+ for (table= thd->open_tables; table; table= table->next)
+ {
+ /* Table might be in use by some outer statement. */
+ DBUG_PRINT("tcache", ("table: '%s' query_id: %lu",
+ table->s->table_name.str, (ulong) table->query_id));
+
+ /* Detach MERGE children after every statement. Even under LOCK TABLES. */
+ if (thd->locked_tables_mode <= LTM_LOCK_TABLES ||
+ table->query_id == thd->query_id)
+ {
+ DBUG_ASSERT(table->file);
+ table->file->extra(HA_EXTRA_DETACH_CHILDREN);
+ }
+ }
+
+ /*
+ We are assuming here that thd->derived_tables contains ONLY derived
+ tables for this substatement. i.e. instead of approach which uses
+ query_id matching for determining which of the derived tables belong
+ to this substatement we rely on the ability of substatements to
+ save/restore thd->derived_tables during their execution.
+
+ TODO: Probably even better approach is to simply associate list of
+ derived tables with (sub-)statement instead of thread and destroy
+ them at the end of its execution.
+ */
+ if (thd->derived_tables)
+ {
+ TABLE *next;
+ /*
+ Close all derived tables generated in queries like
+ SELECT * FROM (SELECT * FROM t1)
+ */
+ for (table= thd->derived_tables ; table ; table= next)
+ {
+ next= table->next;
+ free_tmp_table(thd, table);
+ }
+ thd->derived_tables= 0;
+ }
+
+ if (thd->rec_tables)
+ {
+ TABLE *next;
+ /*
+ Close all temporary tables created for recursive table references.
+ This action was postponed because the table could be used in the
+ statements like ANALYZE WITH r AS (...) SELECT * from r
+ where r is defined through recursion.
+ */
+ for (table= thd->rec_tables ; table ; table= next)
+ {
+ next= table->next;
+ free_tmp_table(thd, table);
+ }
+ thd->rec_tables= 0;
+ }
+
+ /*
+ Mark all temporary tables used by this statement as free for reuse.
+ */
+ thd->mark_tmp_tables_as_free_for_reuse();
+
+ if (thd->locked_tables_mode)
+ {
+
+ /* Ensure we are calling ha_reset() for all used tables */
+ mark_used_tables_as_free_for_reuse(thd, thd->open_tables);
+
+ /*
+ We are under simple LOCK TABLES or we're inside a sub-statement
+ of a prelocked statement, so should not do anything else.
+
+ Note that even if we are in LTM_LOCK_TABLES mode and statement
+ requires prelocking (e.g. when we are closing tables after
+ failing ot "open" all tables required for statement execution)
+ we will exit this function a few lines below.
+ */
+ if (! thd->lex->requires_prelocking())
+ DBUG_RETURN(0);
+
+ /*
+ We are in the top-level statement of a prelocked statement,
+ so we have to leave the prelocked mode now with doing implicit
+ UNLOCK TABLES if needed.
+ */
+ if (thd->locked_tables_mode == LTM_PRELOCKED_UNDER_LOCK_TABLES)
+ thd->locked_tables_mode= LTM_LOCK_TABLES;
+
+ if (thd->locked_tables_mode == LTM_LOCK_TABLES)
+ DBUG_RETURN(0);
+
+ thd->leave_locked_tables_mode();
+
+ /* Fallthrough */
+ }
+
+ if (thd->lock)
+ {
+ /*
+ For RBR we flush the pending event just before we unlock all the
+ tables. This means that we are at the end of a topmost
+ statement, so we ensure that the STMT_END_F flag is set on the
+ pending event. For statements that are *inside* stored
+ functions, the pending event will not be flushed: that will be
+ handled either before writing a query log event (inside
+ binlog_query()) or when preparing a pending event.
+ */
+ (void)thd->binlog_flush_pending_rows_event(TRUE);
+ error= mysql_unlock_tables(thd, thd->lock);
+ thd->lock=0;
+ }
+ /*
+ Closing a MERGE child before the parent would be fatal if the
+ other thread tries to abort the MERGE lock in between.
+ */
+ while (thd->open_tables)
+ (void) close_thread_table(thd, &thd->open_tables);
+
+ DBUG_RETURN(error);
+}
+
+
+/* move one table to free list */
+
+void close_thread_table(THD *thd, TABLE **table_ptr)
+{
+ TABLE *table= *table_ptr;
+ DBUG_ENTER("close_thread_table");
+ DBUG_PRINT("tcache", ("table: '%s'.'%s' %p", table->s->db.str,
+ table->s->table_name.str, table));
+ DBUG_ASSERT(!table->file->keyread_enabled());
+ DBUG_ASSERT(!table->file || table->file->inited == handler::NONE);
+
+ /*
+ The metadata lock must be released after giving back
+ the table to the table cache.
+ */
+ DBUG_ASSERT(thd->mdl_context.is_lock_owner(MDL_key::TABLE,
+ table->s->db.str,
+ table->s->table_name.str,
+ MDL_SHARED));
+ table->mdl_ticket= NULL;
+
+ if (table->file)
+ {
+ table->file->update_global_table_stats();
+ table->file->update_global_index_stats();
+ }
+
+ /*
+ This look is needed to allow THD::notify_shared_lock() to
+ traverse the thd->open_tables list without having to worry that
+ some of the tables are removed from under it
+ */
+
+ mysql_mutex_lock(&thd->LOCK_thd_data);
+ *table_ptr=table->next;
+ mysql_mutex_unlock(&thd->LOCK_thd_data);
+
+ if (! table->needs_reopen())
+ {
+ /* Avoid having MERGE tables with attached children in table cache. */
+ table->file->extra(HA_EXTRA_DETACH_CHILDREN);
+ /* Free memory and reset for next loop. */
+ free_field_buffers_larger_than(table, MAX_TDC_BLOB_SIZE);
+ table->file->ha_reset();
+ }
+
+ /*
+ Do this *before* entering the TABLE_SHARE::tdc.LOCK_table_share
+ critical section.
+ */
+ MYSQL_UNBIND_TABLE(table->file);
+
+ tc_release_table(table);
+ DBUG_VOID_RETURN;
+}
+
+
+/*
+ Find table in list.
+
+ SYNOPSIS
+ find_table_in_list()
+ table Pointer to table list
+ offset Offset to which list in table structure to use
+ db_name Data base name
+ table_name Table name
+
+ NOTES:
+ This is called by find_table_in_global_list().
+
+ RETURN VALUES
+ NULL Table not found
+ # Pointer to found table.
+*/
+
+TABLE_LIST *find_table_in_list(TABLE_LIST *table,
+ TABLE_LIST *TABLE_LIST::*link,
+ const LEX_CSTRING *db_name,
+ const LEX_CSTRING *table_name)
+{
+ for (; table; table= table->*link )
+ {
+ if (cmp(&table->db, db_name) == 0 &&
+ cmp(&table->table_name, table_name) == 0)
+ break;
+ }
+ return table;
+}
+
+
+/**
+ Test that table is unique (It's only exists once in the table list)
+
+ @param thd thread handle
+ @param table table which should be checked
+ @param table_list list of tables
+ @param check_flag whether to check tables' aliases
+ Currently this is only used by INSERT
+
+ NOTE: to exclude derived tables from check we use following mechanism:
+ a) during derived table processing set THD::derived_tables_processing
+ b) JOIN::prepare set SELECT::exclude_from_table_unique_test if
+ THD::derived_tables_processing set. (we can't use JOIN::execute
+ because for PS we perform only JOIN::prepare, but we can't set this
+ flag in JOIN::prepare if we are not sure that we are in derived table
+ processing loop, because multi-update call fix_fields() for some its
+ items (which mean JOIN::prepare for subqueries) before unique_table
+ call to detect which tables should be locked for write).
+ c) find_dup_table skip all tables which belong to SELECT with
+ SELECT::exclude_from_table_unique_test set.
+ Also SELECT::exclude_from_table_unique_test used to exclude from check
+ tables of main SELECT of multi-delete and multi-update
+
+ We also skip tables with TABLE_LIST::prelocking_placeholder set,
+ because we want to allow SELECTs from them, and their modification
+ will rise the error anyway.
+
+ TODO: when we will have table/view change detection we can do this check
+ only once for PS/SP
+
+ @retval !=0 found duplicate
+ @retval 0 if table is unique
+*/
+
+static
+TABLE_LIST* find_dup_table(THD *thd, TABLE_LIST *table, TABLE_LIST *table_list,
+ uint check_flag)
+{
+ TABLE_LIST *res= 0;
+ LEX_CSTRING *d_name, *t_name, *t_alias;
+ DBUG_ENTER("find_dup_table");
+ DBUG_PRINT("enter", ("table alias: %s", table->alias.str));
+
+ /*
+ If this function called for query which update table (INSERT/UPDATE/...)
+ then we have in table->table pointer to TABLE object which we are
+ updating even if it is VIEW so we need TABLE_LIST of this TABLE object
+ to get right names (even if lower_case_table_names used).
+
+ If this function called for CREATE command that we have not opened table
+ (table->table equal to 0) and right names is in current TABLE_LIST
+ object.
+ */
+ if (table->table)
+ {
+ /* All MyISAMMRG children are plain MyISAM tables. */
+ DBUG_ASSERT(table->table->file->ht->db_type != DB_TYPE_MRG_MYISAM);
+
+ table= table->find_underlying_table(table->table);
+ /*
+ as far as we have table->table we have to find real TABLE_LIST of
+ it in underlying tables
+ */
+ DBUG_ASSERT(table);
+ }
+ d_name= &table->db;
+ t_name= &table->table_name;
+ t_alias= &table->alias;
+
+retry:
+ DBUG_PRINT("info", ("real table: %s.%s", d_name->str, t_name->str));
+ for (TABLE_LIST *tl= table_list; tl ; tl= tl->next_global, res= 0)
+ {
+ if (tl->select_lex && tl->select_lex->master_unit() &&
+ tl->select_lex->master_unit()->executed)
+ {
+ /*
+ There is no sense to check tables of already executed parts
+ of the query
+ */
+ continue;
+ }
+ /*
+ Table is unique if it is present only once in the global list
+ of tables and once in the list of table locks.
+ */
+ if (! (res= find_table_in_global_list(tl, d_name, t_name)))
+ break;
+ tl= res; // We can continue search after this table
+
+ /* Skip if same underlying table. */
+ if (res->table && (res->table == table->table))
+ continue;
+
+ /* Skip if table is tmp table */
+ if (check_flag & CHECK_DUP_SKIP_TEMP_TABLE &&
+ res->table && res->table->s->tmp_table != NO_TMP_TABLE)
+ {
+ continue;
+ }
+ if (check_flag & CHECK_DUP_FOR_CREATE)
+ DBUG_RETURN(res);
+
+ /* Skip if table alias does not match. */
+ if (check_flag & CHECK_DUP_ALLOW_DIFFERENT_ALIAS)
+ {
+ if (my_strcasecmp(table_alias_charset, t_alias->str, res->alias.str))
+ continue;
+ }
+
+ /*
+ If table is not excluded (could be a derived table) and table is not
+ a prelocking placeholder then we found either a duplicate entry
+ or a table that is part of a derived table (handled below).
+ Examples are:
+ INSERT INTO t1 SELECT * FROM t1;
+ INSERT INTO t1 SELECT * FROM view_containing_t1;
+ */
+ if (res->select_lex &&
+ !res->select_lex->exclude_from_table_unique_test &&
+ !res->prelocking_placeholder)
+ break;
+
+ /*
+ If we found entry of this table or table of SELECT which already
+ processed in derived table or top select of multi-update/multi-delete
+ (exclude_from_table_unique_test) or prelocking placeholder.
+ */
+ DBUG_PRINT("info",
+ ("found same copy of table or table which we should skip"));
+ }
+ if (res && res->belong_to_derived)
+ {
+ /*
+ We come here for queries of type:
+ INSERT INTO t1 (SELECT tmp.a FROM (select * FROM t1) as tmp);
+
+ Try to fix by materializing the derived table
+ */
+ TABLE_LIST *derived= res->belong_to_derived;
+ if (derived->is_merged_derived() && !derived->derived->is_excluded())
+ {
+ DBUG_PRINT("info",
+ ("convert merged to materialization to resolve the conflict"));
+ derived->change_refs_to_fields();
+ derived->set_materialized_derived();
+ goto retry;
+ }
+ }
+ DBUG_RETURN(res);
+}
+
+
+/**
+ Test that the subject table of INSERT/UPDATE/DELETE/CREATE
+ or (in case of MyISAMMRG) one of its children are not used later
+ in the query.
+
+ For MyISAMMRG tables, it is assumed that all the underlying
+ tables of @c table (if any) are listed right after it and that
+ their @c parent_l field points at the main table.
+
+
+ @retval non-NULL The table list element for the table that
+ represents the duplicate.
+ @retval NULL No duplicates found.
+*/
+
+TABLE_LIST*
+unique_table(THD *thd, TABLE_LIST *table, TABLE_LIST *table_list,
+ uint check_flag)
+{
+ TABLE_LIST *dup;
+
+ table= table->find_table_for_update();
+
+ if (table->table &&
+ table->table->file->ha_table_flags() & HA_CAN_MULTISTEP_MERGE)
+ {
+ TABLE_LIST *child;
+ dup= NULL;
+ /* Check duplicates of all merge children. */
+ for (child= table->next_global; child;
+ child= child->next_global)
+ {
+ if (child->table &&
+ child->table->file->ha_table_flags() & HA_CAN_MULTISTEP_MERGE)
+ continue;
+
+ /*
+ Ensure that the child has one parent that is the table that is
+ updated.
+ */
+ TABLE_LIST *tmp_parent= child;
+ while ((tmp_parent= tmp_parent->parent_l))
+ {
+ if (tmp_parent == table)
+ break;
+ }
+ if (!tmp_parent)
+ break;
+
+ if ((dup= find_dup_table(thd, child, child->next_global, check_flag)))
+ break;
+ }
+ }
+ else
+ dup= find_dup_table(thd, table, table_list, check_flag);
+ return dup;
+}
+
+
+/*
+ Issue correct error message in case we found 2 duplicate tables which
+ prevent some update operation
+
+ SYNOPSIS
+ update_non_unique_table_error()
+ update table which we try to update
+ operation name of update operation
+ duplicate duplicate table which we found
+
+ NOTE:
+ here we hide view underlying tables if we have them
+*/
+
+void update_non_unique_table_error(TABLE_LIST *update,
+ const char *operation,
+ TABLE_LIST *duplicate)
+{
+ update= update->top_table();
+ duplicate= duplicate->top_table();
+ if (!update->view || !duplicate->view ||
+ update->view == duplicate->view ||
+ update->view_name.length != duplicate->view_name.length ||
+ update->view_db.length != duplicate->view_db.length ||
+ lex_string_cmp(table_alias_charset,
+ &update->view_name, &duplicate->view_name) != 0 ||
+ lex_string_cmp(table_alias_charset,
+ &update->view_db, &duplicate->view_db) != 0)
+ {
+ /*
+ it is not the same view repeated (but it can be parts of the same copy
+ of view), so we have to hide underlying tables.
+ */
+ if (update->view)
+ {
+ /* Issue the ER_NON_INSERTABLE_TABLE error for an INSERT */
+ if (update->view == duplicate->view)
+ my_error(!strncmp(operation, "INSERT", 6) ?
+ ER_NON_INSERTABLE_TABLE : ER_NON_UPDATABLE_TABLE, MYF(0),
+ update->alias.str, operation);
+ else
+ my_error(ER_VIEW_PREVENT_UPDATE, MYF(0),
+ (duplicate->view ? duplicate->alias.str : update->alias.str),
+ operation, update->alias.str);
+ return;
+ }
+ if (duplicate->view)
+ {
+ my_error(ER_VIEW_PREVENT_UPDATE, MYF(0), duplicate->alias.str, operation,
+ update->alias.str);
+ return;
+ }
+ }
+ my_error(ER_UPDATE_TABLE_USED, MYF(0), update->alias.str, operation);
+}
+
+
+/**
+ Force all other threads to stop using the table by upgrading
+ metadata lock on it and remove unused TABLE instances from cache.
+
+ @param thd Thread handler
+ @param table Table to remove from cache
+ @param function HA_EXTRA_PREPARE_FOR_DROP if table is to be deleted
+ HA_EXTRA_FORCE_REOPEN if table is not be used
+ HA_EXTRA_PREPARE_FOR_RENAME if table is to be renamed
+ HA_EXTRA_NOT_USED Don't call extra()
+
+ @note When returning, the table will be unusable for other threads
+ until metadata lock is downgraded.
+
+ @retval FALSE Success.
+ @retval TRUE Failure (e.g. because thread was killed).
+*/
+
+bool wait_while_table_is_used(THD *thd, TABLE *table,
+ enum ha_extra_function function)
+{
+ DBUG_ENTER("wait_while_table_is_used");
+ DBUG_ASSERT(!table->s->tmp_table);
+ DBUG_PRINT("enter", ("table: '%s' share: %p db_stat: %u",
+ table->s->table_name.str, table->s,
+ table->db_stat));
+
+ if (thd->mdl_context.upgrade_shared_lock(
+ table->mdl_ticket, MDL_EXCLUSIVE,
+ thd->variables.lock_wait_timeout))
+ DBUG_RETURN(TRUE);
+
+ table->s->tdc->flush(thd, true);
+ /* extra() call must come only after all instances above are closed */
+ if (function != HA_EXTRA_NOT_USED)
+ {
+ int error= table->file->extra(function);
+ if (error)
+ table->file->print_error(error, MYF(0));
+ DBUG_RETURN(error);
+ }
+ DBUG_RETURN(FALSE);
+}
+
+
+/**
+ Close a and drop a just created table in CREATE TABLE ... SELECT.
+
+ @param thd Thread handle
+ @param table TABLE object for the table to be dropped
+ @param db_name Name of database for this table
+ @param table_name Name of this table
+
+ This routine assumes that the table to be closed is open only
+ by the calling thread, so we needn't wait until other threads
+ close the table. It also assumes that the table is first
+ in thd->open_ables and a data lock on it, if any, has been
+ released. To sum up, it's tuned to work with
+ CREATE TABLE ... SELECT and CREATE TABLE .. SELECT only.
+ Note, that currently CREATE TABLE ... SELECT is not supported
+ under LOCK TABLES. This function, still, can be called in
+ prelocked mode, e.g. if we do CREATE TABLE .. SELECT f1();
+*/
+
+void drop_open_table(THD *thd, TABLE *table, const LEX_CSTRING *db_name,
+ const LEX_CSTRING *table_name)
+{
+ DBUG_ENTER("drop_open_table");
+ if (table->s->tmp_table)
+ thd->drop_temporary_table(table, NULL, true);
+ else
+ {
+ DBUG_ASSERT(table == thd->open_tables);
+
+ handlerton *table_type= table->s->db_type();
+ table->file->extra(HA_EXTRA_PREPARE_FOR_DROP);
+ table->s->tdc->flush(thd, true);
+ close_thread_table(thd, &thd->open_tables);
+ /* Remove the table from the storage engine and rm the .frm. */
+ quick_rm_table(thd, table_type, db_name, table_name, 0);
+ }
+ DBUG_VOID_RETURN;
+}
+
+
+/**
+ An error handler which converts, if possible, ER_LOCK_DEADLOCK error
+ that can occur when we are trying to acquire a metadata lock to
+ a request for back-off and re-start of open_tables() process.
+*/
+
+class MDL_deadlock_handler : public Internal_error_handler
+{
+public:
+ MDL_deadlock_handler(Open_table_context *ot_ctx_arg)
+ : m_ot_ctx(ot_ctx_arg), m_is_active(FALSE)
+ {}
+
+ virtual ~MDL_deadlock_handler() {}
+
+ virtual bool handle_condition(THD *thd,
+ uint sql_errno,
+ const char* sqlstate,
+ Sql_condition::enum_warning_level *level,
+ const char* msg,
+ Sql_condition ** cond_hdl);
+
+private:
+ /** Open table context to be used for back-off request. */
+ Open_table_context *m_ot_ctx;
+ /**
+ Indicates that we are already in the process of handling
+ ER_LOCK_DEADLOCK error. Allows to re-emit the error from
+ the error handler without falling into infinite recursion.
+ */
+ bool m_is_active;
+};
+
+
+bool MDL_deadlock_handler::handle_condition(THD *,
+ uint sql_errno,
+ const char*,
+ Sql_condition::enum_warning_level*,
+ const char*,
+ Sql_condition ** cond_hdl)
+{
+ *cond_hdl= NULL;
+ if (! m_is_active && sql_errno == ER_LOCK_DEADLOCK)
+ {
+ /* Disable the handler to avoid infinite recursion. */
+ m_is_active= TRUE;
+ (void) m_ot_ctx->request_backoff_action(
+ Open_table_context::OT_BACKOFF_AND_RETRY,
+ NULL);
+ m_is_active= FALSE;
+ /*
+ If the above back-off request failed, a new instance of
+ ER_LOCK_DEADLOCK error was emitted. Thus the current
+ instance of error condition can be treated as handled.
+ */
+ return TRUE;
+ }
+ return FALSE;
+}
+
+
+/**
+ Try to acquire an MDL lock for a table being opened.
+
+ @param[in,out] thd Session context, to report errors.
+ @param[out] ot_ctx Open table context, to hold the back off
+ state. If we failed to acquire a lock
+ due to a lock conflict, we add the
+ failed request to the open table context.
+ @param[in,out] mdl_request A request for an MDL lock.
+ If we managed to acquire a ticket
+ (no errors or lock conflicts occurred),
+ contains a reference to it on
+ return. However, is not modified if MDL
+ lock type- modifying flags were provided.
+ @param[in] flags flags MYSQL_OPEN_FORCE_SHARED_MDL,
+ MYSQL_OPEN_FORCE_SHARED_HIGH_PRIO_MDL or
+ MYSQL_OPEN_FAIL_ON_MDL_CONFLICT
+ @sa open_table().
+ @param[out] mdl_ticket Only modified if there was no error.
+ If we managed to acquire an MDL
+ lock, contains a reference to the
+ ticket, otherwise is set to NULL.
+
+ @retval TRUE An error occurred.
+ @retval FALSE No error, but perhaps a lock conflict, check mdl_ticket.
+*/
+
+static bool
+open_table_get_mdl_lock(THD *thd, Open_table_context *ot_ctx,
+ MDL_request *mdl_request,
+ uint flags,
+ MDL_ticket **mdl_ticket)
+{
+ MDL_request mdl_request_shared;
+
+ if (flags & (MYSQL_OPEN_FORCE_SHARED_MDL |
+ MYSQL_OPEN_FORCE_SHARED_HIGH_PRIO_MDL))
+ {
+ /*
+ MYSQL_OPEN_FORCE_SHARED_MDL flag means that we are executing
+ PREPARE for a prepared statement and want to override
+ the type-of-operation aware metadata lock which was set
+ in the parser/during view opening with a simple shared
+ metadata lock.
+ This is necessary to allow concurrent execution of PREPARE
+ and LOCK TABLES WRITE statement against the same table.
+
+ MYSQL_OPEN_FORCE_SHARED_HIGH_PRIO_MDL flag means that we open
+ the table in order to get information about it for one of I_S
+ queries and also want to override the type-of-operation aware
+ shared metadata lock which was set earlier (e.g. during view
+ opening) with a high-priority shared metadata lock.
+ This is necessary to avoid unnecessary waiting and extra
+ ER_WARN_I_S_SKIPPED_TABLE warnings when accessing I_S tables.
+
+ These two flags are mutually exclusive.
+ */
+ DBUG_ASSERT(!(flags & MYSQL_OPEN_FORCE_SHARED_MDL) ||
+ !(flags & MYSQL_OPEN_FORCE_SHARED_HIGH_PRIO_MDL));
+
+ MDL_REQUEST_INIT_BY_KEY(&mdl_request_shared, &mdl_request->key,
+ flags & MYSQL_OPEN_FORCE_SHARED_MDL ? MDL_SHARED : MDL_SHARED_HIGH_PRIO,
+ MDL_TRANSACTION);
+ mdl_request= &mdl_request_shared;
+ }
+
+ if (flags & MYSQL_OPEN_FAIL_ON_MDL_CONFLICT)
+ {
+ /*
+ When table is being open in order to get data for I_S table,
+ we might have some tables not only open but also locked (e.g. when
+ this happens under LOCK TABLES or in a stored function).
+ As a result by waiting on a conflicting metadata lock to go away
+ we may create a deadlock which won't entirely belong to the
+ MDL subsystem and thus won't be detectable by this subsystem's
+ deadlock detector.
+ To avoid such situation we skip the trouble-making table if
+ there is a conflicting lock.
+ */
+ if (thd->mdl_context.try_acquire_lock(mdl_request))
+ return TRUE;
+ if (mdl_request->ticket == NULL)
+ {
+ my_error(ER_WARN_I_S_SKIPPED_TABLE, MYF(0),
+ mdl_request->key.db_name(), mdl_request->key.name());
+ return TRUE;
+ }
+ }
+ else
+ {
+ /*
+ We are doing a normal table open. Let us try to acquire a metadata
+ lock on the table. If there is a conflicting lock, acquire_lock()
+ will wait for it to go away. Sometimes this waiting may lead to a
+ deadlock, with the following results:
+ 1) If a deadlock is entirely within MDL subsystem, it is
+ detected by the deadlock detector of this subsystem.
+ ER_LOCK_DEADLOCK error is produced. Then, the error handler
+ that is installed prior to the call to acquire_lock() attempts
+ to request a back-off and retry. Upon success, ER_LOCK_DEADLOCK
+ error is suppressed, otherwise propagated up the calling stack.
+ 2) Otherwise, a deadlock may occur when the wait-for graph
+ includes edges not visible to the MDL deadlock detector.
+ One such example is a wait on an InnoDB row lock, e.g. when:
+ conn C1 gets SR MDL lock on t1 with SELECT * FROM t1
+ conn C2 gets a row lock on t2 with SELECT * FROM t2 FOR UPDATE
+ conn C3 gets in and waits on C1 with DROP TABLE t0, t1
+ conn C2 continues and blocks on C3 with SELECT * FROM t0
+ conn C1 deadlocks by waiting on C2 by issuing SELECT * FROM
+ t2 LOCK IN SHARE MODE.
+ Such circular waits are currently only resolved by timeouts,
+ e.g. @@innodb_lock_wait_timeout or @@lock_wait_timeout.
+ */
+ MDL_deadlock_handler mdl_deadlock_handler(ot_ctx);
+
+ thd->push_internal_handler(&mdl_deadlock_handler);
+ bool result= thd->mdl_context.acquire_lock(mdl_request,
+ ot_ctx->get_timeout());
+ thd->pop_internal_handler();
+
+ if (result && !ot_ctx->can_recover_from_failed_open())
+ return TRUE;
+ }
+ *mdl_ticket= mdl_request->ticket;
+ return FALSE;
+}
+
+#ifdef WITH_PARTITION_STORAGE_ENGINE
+/* Set all [named] partitions as used. */
+static int set_partitions_as_used(TABLE_LIST *tl, TABLE *t)
+{
+ if (t->part_info)
+ return t->file->change_partitions_to_open(tl->partition_names);
+ return 0;
+}
+#endif
+
+
+/**
+ Check if the given table is actually a VIEW that was LOCK-ed
+
+ @param thd Thread context.
+ @param t Table to check.
+
+ @retval TRUE The 't'-table is a locked view
+ needed to remedy problem before retrying again.
+ @retval FALSE 't' was not locked, not a VIEW or an error happened.
+*/
+
+bool is_locked_view(THD *thd, TABLE_LIST *t)
+{
+ DBUG_ENTER("is_locked_view");
+ /*
+ Is this table a view and not a base table?
+ (it is work around to allow to open view with locked tables,
+ real fix will be made after definition cache will be made)
+
+ Since opening of view which was not explicitly locked by LOCK
+ TABLES breaks metadata locking protocol (potentially can lead
+ to deadlocks) it should be disallowed.
+ */
+ if (thd->mdl_context.is_lock_owner(MDL_key::TABLE, t->db.str,
+ t->table_name.str, MDL_SHARED))
+ {
+ char path[FN_REFLEN + 1];
+ build_table_filename(path, sizeof(path) - 1,
+ t->db.str, t->table_name.str, reg_ext, 0);
+ /*
+ Note that we can't be 100% sure that it is a view since it's
+ possible that we either simply have not found unused TABLE
+ instance in THD::open_tables list or were unable to open table
+ during prelocking process (in this case in theory we still
+ should hold shared metadata lock on it).
+ */
+ if (dd_frm_is_view(thd, path))
+ {
+ /*
+ If parent_l of the table_list is non null then a merge table
+ has this view as child table, which is not supported.
+ */
+ if (t->parent_l)
+ {
+ my_error(ER_WRONG_MRG_TABLE, MYF(0));
+ DBUG_RETURN(FALSE);
+ }
+
+ if (!tdc_open_view(thd, t, CHECK_METADATA_VERSION))
+ {
+ DBUG_ASSERT(t->view != 0);
+ DBUG_RETURN(TRUE); // VIEW
+ }
+ }
+ }
+
+ DBUG_RETURN(FALSE);
+}
+
+
+/**
+ Open a base table.
+
+ @param thd Thread context.
+ @param table_list Open first table in list.
+ @param ot_ctx Context with flags which modify how open works
+ and which is used to recover from a failed
+ open_table() attempt.
+ Some examples of flags:
+ MYSQL_OPEN_IGNORE_FLUSH - Open table even if
+ someone has done a flush. No version number
+ checking is done.
+ MYSQL_OPEN_HAS_MDL_LOCK - instead of acquiring
+ metadata locks rely on that caller already has
+ appropriate ones.
+
+ Uses a cache of open tables to find a TABLE instance not in use.
+
+ If TABLE_LIST::open_strategy is set to OPEN_IF_EXISTS, the table is
+ opened only if it exists. If the open strategy is OPEN_STUB, the
+ underlying table is never opened. In both cases, metadata locks are
+ always taken according to the lock strategy.
+
+ The function used to open temporary tables, but now it opens base tables
+ only.
+
+ @retval TRUE Open failed. "action" parameter may contain type of action
+ needed to remedy problem before retrying again.
+ @retval FALSE Success. Members of TABLE_LIST structure are filled properly
+ (e.g. TABLE_LIST::table is set for real tables and
+ TABLE_LIST::view is set for views).
+*/
+
+bool open_table(THD *thd, TABLE_LIST *table_list, Open_table_context *ot_ctx)
+{
+ TABLE *table;
+ const char *key;
+ uint key_length;
+ const char *alias= table_list->alias.str;
+ uint flags= ot_ctx->get_flags();
+ MDL_ticket *mdl_ticket;
+ TABLE_SHARE *share;
+ uint gts_flags;
+#ifdef WITH_PARTITION_STORAGE_ENGINE
+ int part_names_error=0;
+#endif
+ DBUG_ENTER("open_table");
+
+ /*
+ The table must not be opened already. The table can be pre-opened for
+ some statements if it is a temporary table.
+
+ open_temporary_table() must be used to open temporary tables.
+ */
+ DBUG_ASSERT(!table_list->table);
+
+ /* an open table operation needs a lot of the stack space */
+ if (check_stack_overrun(thd, STACK_MIN_SIZE_FOR_OPEN, (uchar *)&alias))
+ DBUG_RETURN(TRUE);
+
+ if (!(flags & MYSQL_OPEN_IGNORE_KILLED) && thd->killed)
+ {
+ thd->send_kill_message();
+ DBUG_RETURN(TRUE);
+ }
+
+ /*
+ Check if we're trying to take a write lock in a read only transaction.
+
+ Note that we allow write locks on log tables as otherwise logging
+ to general/slow log would be disabled in read only transactions.
+ */
+ if (table_list->mdl_request.is_write_lock_request() &&
+ thd->tx_read_only &&
+ !(flags & (MYSQL_LOCK_LOG_TABLE | MYSQL_OPEN_HAS_MDL_LOCK)))
+ {
+ my_error(ER_CANT_EXECUTE_IN_READ_ONLY_TRANSACTION, MYF(0));
+ DBUG_RETURN(true);
+ }
+
+ if (!table_list->db.str)
+ {
+ my_error(ER_NO_DB_ERROR, MYF(0));
+ DBUG_RETURN(true);
+ }
+
+ key_length= get_table_def_key(table_list, &key);
+
+ /*
+ If we're in pre-locked or LOCK TABLES mode, let's try to find the
+ requested table in the list of pre-opened and locked tables. If the
+ table is not there, return an error - we can't open not pre-opened
+ tables in pre-locked/LOCK TABLES mode.
+ TODO: move this block into a separate function.
+ */
+ if (thd->locked_tables_mode &&
+ ! (flags & MYSQL_OPEN_GET_NEW_TABLE))
+ { // Using table locks
+ TABLE *best_table= 0;
+ int best_distance= INT_MIN;
+ for (table=thd->open_tables; table ; table=table->next)
+ {
+ if (table->s->table_cache_key.length == key_length &&
+ !memcmp(table->s->table_cache_key.str, key, key_length))
+ {
+ if (!my_strcasecmp(system_charset_info, table->alias.c_ptr(), alias) &&
+ table->query_id != thd->query_id && /* skip tables already used */
+ (thd->locked_tables_mode == LTM_LOCK_TABLES ||
+ table->query_id == 0))
+ {
+ int distance= ((int) table->reginfo.lock_type -
+ (int) table_list->lock_type);
+
+ /*
+ Find a table that either has the exact lock type requested,
+ or has the best suitable lock. In case there is no locked
+ table that has an equal or higher lock than requested,
+ we us the closest matching lock to be able to produce an error
+ message about wrong lock mode on the table. The best_table
+ is changed if bd < 0 <= d or bd < d < 0 or 0 <= d < bd.
+
+ distance < 0 - No suitable lock found
+ distance > 0 - we have lock mode higher then we require
+ distance == 0 - we have lock mode exactly which we need
+ */
+ if ((best_distance < 0 && distance > best_distance) ||
+ (distance >= 0 && distance < best_distance))
+ {
+ best_distance= distance;
+ best_table= table;
+ if (best_distance == 0)
+ {
+ /*
+ We have found a perfect match and can finish iterating
+ through open tables list. Check for table use conflict
+ between calling statement and SP/trigger is done in
+ lock_tables().
+ */
+ break;
+ }
+ }
+ }
+ }
+ }
+ if (best_table)
+ {
+ table= best_table;
+ table->query_id= thd->query_id;
+ table->init(thd, table_list);
+ DBUG_PRINT("info",("Using locked table"));
+#ifdef WITH_PARTITION_STORAGE_ENGINE
+ part_names_error= set_partitions_as_used(table_list, table);
+#endif
+ goto reset;
+ }
+
+ if (is_locked_view(thd, table_list))
+ {
+ if (table_list->sequence)
+ {
+ my_error(ER_NOT_SEQUENCE, MYF(0), table_list->db.str, table_list->alias.str);
+ DBUG_RETURN(true);
+ }
+ DBUG_RETURN(FALSE); // VIEW
+ }
+
+ /*
+ No table in the locked tables list. In case of explicit LOCK TABLES
+ this can happen if a user did not include the table into the list.
+ In case of pre-locked mode locked tables list is generated automatically,
+ so we may only end up here if the table did not exist when
+ locked tables list was created.
+ */
+ if (thd->locked_tables_mode == LTM_PRELOCKED)
+ my_error(ER_NO_SUCH_TABLE, MYF(0), table_list->db.str, table_list->alias.str);
+ else
+ my_error(ER_TABLE_NOT_LOCKED, MYF(0), alias);
+ DBUG_RETURN(TRUE);
+ }
+
+ /*
+ Non pre-locked/LOCK TABLES mode, and the table is not temporary.
+ This is the normal use case.
+ */
+
+ if (! (flags & MYSQL_OPEN_HAS_MDL_LOCK))
+ {
+ if (open_table_get_mdl_lock(thd, ot_ctx, &table_list->mdl_request,
+ flags, &mdl_ticket) ||
+ mdl_ticket == NULL)
+ {
+ DEBUG_SYNC(thd, "before_open_table_wait_refresh");
+ DBUG_RETURN(TRUE);
+ }
+ DEBUG_SYNC(thd, "after_open_table_mdl_shared");
+ }
+ else
+ {
+ /*
+ Grab reference to the MDL lock ticket that was acquired
+ by the caller.
+ */
+ mdl_ticket= table_list->mdl_request.ticket;
+ }
+
+ if (table_list->open_strategy == TABLE_LIST::OPEN_IF_EXISTS)
+ {
+ if (!ha_table_exists(thd, &table_list->db, &table_list->table_name))
+ DBUG_RETURN(FALSE);
+ }
+ else if (table_list->open_strategy == TABLE_LIST::OPEN_STUB)
+ DBUG_RETURN(FALSE);
+
+ /* Table exists. Let us try to open it. */
+
+ if (table_list->i_s_requested_object & OPEN_TABLE_ONLY)
+ gts_flags= GTS_TABLE;
+ else if (table_list->i_s_requested_object & OPEN_VIEW_ONLY)
+ gts_flags= GTS_VIEW;
+ else
+ gts_flags= GTS_TABLE | GTS_VIEW;
+
+retry_share:
+
+ share= tdc_acquire_share(thd, table_list, gts_flags, &table);
+
+ if (unlikely(!share))
+ {
+ /*
+ Hide "Table doesn't exist" errors if the table belongs to a view.
+ The check for thd->is_error() is necessary to not push an
+ unwanted error in case the error was already silenced.
+ @todo Rework the alternative ways to deal with ER_NO_SUCH TABLE.
+ */
+ if (thd->is_error())
+ {
+ if (table_list->parent_l)
+ {
+ thd->clear_error();
+ my_error(ER_WRONG_MRG_TABLE, MYF(0));
+ }
+ else if (table_list->belong_to_view)
+ {
+ TABLE_LIST *view= table_list->belong_to_view;
+ thd->clear_error();
+ my_error(ER_VIEW_INVALID, MYF(0),
+ view->view_db.str, view->view_name.str);
+ }
+ }
+ DBUG_RETURN(TRUE);
+ }
+
+ /*
+ Check if this TABLE_SHARE-object corresponds to a view. Note, that there is
+ no need to check TABLE_SHARE::tdc.flushed as we do for regular tables,
+ because view shares are always up to date.
+ */
+ if (share->is_view)
+ {
+ /*
+ If parent_l of the table_list is non null then a merge table
+ has this view as child table, which is not supported.
+ */
+ if (table_list->parent_l)
+ {
+ my_error(ER_WRONG_MRG_TABLE, MYF(0));
+ goto err_lock;
+ }
+ if (table_list->sequence)
+ {
+ my_error(ER_NOT_SEQUENCE, MYF(0), table_list->db.str,
+ table_list->alias.str);
+ goto err_lock;
+ }
+ /*
+ This table is a view. Validate its metadata version: in particular,
+ that it was a view when the statement was prepared.
+ */
+ if (check_and_update_table_version(thd, table_list, share))
+ goto err_lock;
+
+ /* Open view */
+ if (mysql_make_view(thd, share, table_list, false))
+ goto err_lock;
+
+ /* TODO: Don't free this */
+ tdc_release_share(share);
+
+ DBUG_ASSERT(table_list->view);
+
+ DBUG_RETURN(FALSE);
+ }
+
+#ifdef WITH_WSREP
+ if (!((flags & MYSQL_OPEN_IGNORE_FLUSH) ||
+ (thd->wsrep_applier)))
+#else
+ if (!(flags & MYSQL_OPEN_IGNORE_FLUSH))
+#endif
+ {
+ if (share->tdc->flushed)
+ {
+ /*
+ We already have an MDL lock. But we have encountered an old
+ version of table in the table definition cache which is possible
+ when someone changes the table version directly in the cache
+ without acquiring a metadata lock (e.g. this can happen during
+ "rolling" FLUSH TABLE(S)).
+ Release our reference to share, wait until old version of
+ share goes away and then try to get new version of table share.
+ */
+ if (table)
+ tc_release_table(table);
+ else
+ tdc_release_share(share);
+
+ MDL_deadlock_handler mdl_deadlock_handler(ot_ctx);
+ bool wait_result;
+
+ thd->push_internal_handler(&mdl_deadlock_handler);
+ wait_result= tdc_wait_for_old_version(thd, table_list->db.str,
+ table_list->table_name.str,
+ ot_ctx->get_timeout(),
+ mdl_ticket->get_deadlock_weight());
+ thd->pop_internal_handler();
+
+ if (wait_result)
+ DBUG_RETURN(TRUE);
+
+ goto retry_share;
+ }
+
+ if (thd->open_tables && thd->open_tables->s->tdc->flushed)
+ {
+ /*
+ If the version changes while we're opening the tables,
+ we have to back off, close all the tables opened-so-far,
+ and try to reopen them. Note: refresh_version is currently
+ changed only during FLUSH TABLES.
+ */
+ if (table)
+ tc_release_table(table);
+ else
+ tdc_release_share(share);
+ (void)ot_ctx->request_backoff_action(Open_table_context::OT_REOPEN_TABLES,
+ NULL);
+ DBUG_RETURN(TRUE);
+ }
+ }
+
+ if (table)
+ {
+ DBUG_ASSERT(table->file != NULL);
+ if (table->file->discover_check_version())
+ {
+ tc_release_table(table);
+ (void) ot_ctx->request_backoff_action(Open_table_context::OT_DISCOVER,
+ table_list);
+ DBUG_RETURN(TRUE);
+ }
+ table->file->rebind_psi();
+#ifdef WITH_PARTITION_STORAGE_ENGINE
+ part_names_error= set_partitions_as_used(table_list, table);
+#endif
+ }
+ else
+ {
+ enum open_frm_error error;
+ /* make a new table */
+ if (!(table=(TABLE*) my_malloc(key_memory_TABLE, sizeof(*table),
+ MYF(MY_WME))))
+ goto err_lock;
+
+ error= open_table_from_share(thd, share, &table_list->alias,
+ HA_OPEN_KEYFILE | HA_TRY_READ_ONLY,
+ EXTRA_RECORD,
+ thd->open_options, table, FALSE,
+ IF_PARTITIONING(table_list->partition_names,0));
+
+ if (unlikely(error))
+ {
+ my_free(table);
+
+ if (error == OPEN_FRM_DISCOVER)
+ (void) ot_ctx->request_backoff_action(Open_table_context::OT_DISCOVER,
+ table_list);
+ else if (share->crashed)
+ {
+ if (!(flags & MYSQL_OPEN_IGNORE_REPAIR))
+ (void) ot_ctx->request_backoff_action(Open_table_context::OT_REPAIR,
+ table_list);
+ else
+ table_list->crashed= 1; /* Mark that table was crashed */
+ }
+ goto err_lock;
+ }
+ if (open_table_entry_fini(thd, share, table))
+ {
+ closefrm(table);
+ my_free(table);
+ goto err_lock;
+ }
+
+ /* Add table to the share's used tables list. */
+ tc_add_table(thd, table);
+ }
+
+ if (!(flags & MYSQL_OPEN_HAS_MDL_LOCK) &&
+ table->s->table_category < TABLE_CATEGORY_INFORMATION)
+ {
+ /*
+ We are not under LOCK TABLES and going to acquire write-lock/
+ modify the base table. We need to acquire protection against
+ global read lock until end of this statement in order to have
+ this statement blocked by active FLUSH TABLES WITH READ LOCK.
+
+ We don't need to acquire this protection under LOCK TABLES as
+ such protection already acquired at LOCK TABLES time and
+ not released until UNLOCK TABLES.
+
+ We don't block statements which modify only temporary tables
+ as these tables are not preserved by any form of
+ backup which uses FLUSH TABLES WITH READ LOCK.
+
+ TODO: The fact that we sometimes acquire protection against
+ GRL only when we encounter table to be write-locked
+ slightly increases probability of deadlock.
+ This problem will be solved once Alik pushes his
+ temporary table refactoring patch and we can start
+ pre-acquiring metadata locks at the beggining of
+ open_tables() call.
+ */
+ enum enum_mdl_type mdl_type= MDL_BACKUP_DML;
+
+ if (table->s->table_category != TABLE_CATEGORY_USER)
+ mdl_type= MDL_BACKUP_SYS_DML;
+ else if (table->s->online_backup)
+ mdl_type= MDL_BACKUP_TRANS_DML;
+
+ if (table_list->mdl_request.is_write_lock_request() &&
+ ! (flags & (MYSQL_OPEN_IGNORE_GLOBAL_READ_LOCK |
+ MYSQL_OPEN_FORCE_SHARED_MDL |
+ MYSQL_OPEN_FORCE_SHARED_HIGH_PRIO_MDL |
+ MYSQL_OPEN_SKIP_SCOPED_MDL_LOCK)) &&
+ ! ot_ctx->has_protection_against_grl(mdl_type))
+ {
+ MDL_request protection_request;
+ MDL_deadlock_handler mdl_deadlock_handler(ot_ctx);
+
+ if (thd->has_read_only_protection())
+ {
+ MYSQL_UNBIND_TABLE(table->file);
+ tc_release_table(table);
+ DBUG_RETURN(TRUE);
+ }
+
+ MDL_REQUEST_INIT(&protection_request, MDL_key::BACKUP, "", "", mdl_type,
+ MDL_STATEMENT);
+
+ /*
+ Install error handler which if possible will convert deadlock error
+ into request to back-off and restart process of opening tables.
+ */
+ thd->push_internal_handler(&mdl_deadlock_handler);
+ bool result= thd->mdl_context.acquire_lock(&protection_request,
+ ot_ctx->get_timeout());
+ thd->pop_internal_handler();
+
+ if (result)
+ {
+ MYSQL_UNBIND_TABLE(table->file);
+ tc_release_table(table);
+ DBUG_RETURN(TRUE);
+ }
+
+ ot_ctx->set_has_protection_against_grl(mdl_type);
+ }
+ }
+
+ table->mdl_ticket= mdl_ticket;
+ table->reginfo.lock_type=TL_READ; /* Assume read */
+
+ table->init(thd, table_list);
+
+ table->next= thd->open_tables; /* Link into simple list */
+ thd->set_open_tables(table);
+
+ reset:
+ /*
+ Check that there is no reference to a condition from an earlier query
+ (cf. Bug#58553).
+ */
+ DBUG_ASSERT(table->file->pushed_cond == NULL);
+ table_list->updatable= 1; // It is not derived table nor non-updatable VIEW
+ table_list->table= table;
+
+#ifdef WITH_PARTITION_STORAGE_ENGINE
+ if (unlikely(table->part_info))
+ {
+ /* Partitions specified were incorrect.*/
+ if (part_names_error)
+ {
+ table->file->print_error(part_names_error, MYF(0));
+ DBUG_RETURN(true);
+ }
+ }
+ else if (table_list->partition_names)
+ {
+ /* Don't allow PARTITION () clause on a nonpartitioned table */
+ my_error(ER_PARTITION_CLAUSE_ON_NONPARTITIONED, MYF(0));
+ DBUG_RETURN(true);
+ }
+#endif
+ if (table_list->sequence && table->s->table_type != TABLE_TYPE_SEQUENCE)
+ {
+ my_error(ER_NOT_SEQUENCE, MYF(0), table_list->db.str, table_list->alias.str);
+ DBUG_RETURN(true);
+ }
+
+ DBUG_ASSERT(thd->locked_tables_mode || table->file->row_logging == 0);
+ DBUG_RETURN(false);
+
+err_lock:
+ tdc_release_share(share);
+
+ DBUG_PRINT("exit", ("failed"));
+ DBUG_RETURN(true);
+}
+
+
+/**
+ Find table in the list of open tables.
+
+ @param list List of TABLE objects to be inspected.
+ @param db Database name
+ @param table_name Table name
+
+ @return Pointer to the TABLE object found, 0 if no table found.
+*/
+
+TABLE *find_locked_table(TABLE *list, const char *db, const char *table_name)
+{
+ char key[MAX_DBKEY_LENGTH];
+ uint key_length= tdc_create_key(key, db, table_name);
+
+ for (TABLE *table= list; table ; table=table->next)
+ {
+ if (table->s->table_cache_key.length == key_length &&
+ !memcmp(table->s->table_cache_key.str, key, key_length))
+ return table;
+ }
+ return(0);
+}
+
+
+/**
+ Find instance of TABLE with upgradable or exclusive metadata
+ lock from the list of open tables, emit error if no such table
+ found.
+
+ @param thd Thread context
+ @param db Database name.
+ @param table_name Name of table.
+ @param p_error In the case of an error (when the function returns NULL)
+ the error number is stored there.
+ If the p_error is NULL, function launches the error itself.
+
+ @note This function checks if the connection holds a global IX
+ metadata lock. If no such lock is found, it is not safe to
+ upgrade the lock and ER_TABLE_NOT_LOCKED_FOR_WRITE will be
+ reported.
+
+ @return Pointer to TABLE instance with MDL_SHARED_UPGRADABLE
+ MDL_SHARED_NO_WRITE, MDL_SHARED_NO_READ_WRITE, or
+ MDL_EXCLUSIVE metadata lock, NULL otherwise.
+*/
+
+TABLE *find_table_for_mdl_upgrade(THD *thd, const char *db,
+ const char *table_name, int *p_error)
+{
+ TABLE *tab= find_locked_table(thd->open_tables, db, table_name);
+ int error;
+
+ if (unlikely(!tab))
+ {
+ error= ER_TABLE_NOT_LOCKED;
+ goto err_exit;
+ }
+
+ /*
+ It is not safe to upgrade the metadata lock without a global IX lock.
+ This can happen with FLUSH TABLES <list> WITH READ LOCK as we in these
+ cases don't take a global IX lock in order to be compatible with
+ global read lock.
+ */
+ if (unlikely(!thd->mdl_context.is_lock_owner(MDL_key::BACKUP, "", "",
+ MDL_BACKUP_DDL)))
+ {
+ error= ER_TABLE_NOT_LOCKED_FOR_WRITE;
+ goto err_exit;
+ }
+
+ while (tab->mdl_ticket != NULL &&
+ !tab->mdl_ticket->is_upgradable_or_exclusive() &&
+ (tab= find_locked_table(tab->next, db, table_name)))
+ continue;
+
+ if (unlikely(!tab))
+ {
+ error= ER_TABLE_NOT_LOCKED_FOR_WRITE;
+ goto err_exit;
+ }
+
+ return tab;
+
+err_exit:
+ if (p_error)
+ *p_error= error;
+ else
+ my_error(error, MYF(0), table_name);
+
+ return NULL;
+}
+
+
+/***********************************************************************
+ class Locked_tables_list implementation. Declared in sql_class.h
+************************************************************************/
+
+/**
+ Enter LTM_LOCK_TABLES mode.
+
+ Enter the LOCK TABLES mode using all the tables that are
+ currently open and locked in this connection.
+ Initializes a TABLE_LIST instance for every locked table.
+
+ @param thd thread handle
+
+ @return TRUE if out of memory.
+*/
+
+bool
+Locked_tables_list::init_locked_tables(THD *thd)
+{
+ DBUG_ASSERT(thd->locked_tables_mode == LTM_NONE);
+ DBUG_ASSERT(m_locked_tables == NULL);
+ DBUG_ASSERT(m_reopen_array == NULL);
+ DBUG_ASSERT(m_locked_tables_count == 0);
+
+ for (TABLE *table= thd->open_tables; table;
+ table= table->next, m_locked_tables_count++)
+ {
+ TABLE_LIST *src_table_list= table->pos_in_table_list;
+ LEX_CSTRING db, table_name, alias;
+
+ db.length= table->s->db.length;
+ table_name.length= table->s->table_name.length;
+ alias.length= table->alias.length();
+ TABLE_LIST *dst_table_list;
+
+ if (! multi_alloc_root(&m_locked_tables_root,
+ &dst_table_list, sizeof(*dst_table_list),
+ &db.str, (size_t) db.length + 1,
+ &table_name.str, (size_t) table_name.length + 1,
+ &alias.str, (size_t) alias.length + 1,
+ NullS))
+ {
+ reset();
+ return TRUE;
+ }
+
+ memcpy((char*) db.str, table->s->db.str, db.length + 1);
+ memcpy((char*) table_name.str, table->s->table_name.str,
+ table_name.length + 1);
+ memcpy((char*) alias.str, table->alias.c_ptr(), alias.length + 1);
+ dst_table_list->init_one_table(&db, &table_name,
+ &alias, table->reginfo.lock_type);
+ dst_table_list->table= table;
+ dst_table_list->mdl_request.ticket= src_table_list->mdl_request.ticket;
+
+ /* Link last into the list of tables */
+ *(dst_table_list->prev_global= m_locked_tables_last)= dst_table_list;
+ m_locked_tables_last= &dst_table_list->next_global;
+ table->pos_in_locked_tables= dst_table_list;
+ }
+ if (m_locked_tables_count)
+ {
+ /**
+ Allocate an auxiliary array to pass to mysql_lock_tables()
+ in reopen_tables(). reopen_tables() is a critical
+ path and we don't want to complicate it with extra allocations.
+ */
+ m_reopen_array= (TABLE_LIST**)alloc_root(&m_locked_tables_root,
+ sizeof(TABLE_LIST*) *
+ (m_locked_tables_count+1));
+ if (m_reopen_array == NULL)
+ {
+ reset();
+ return TRUE;
+ }
+ }
+
+ TRANSACT_TRACKER(add_trx_state(thd, TX_LOCKED_TABLES));
+
+ thd->enter_locked_tables_mode(LTM_LOCK_TABLES);
+
+ return FALSE;
+}
+
+
+/**
+ Leave LTM_LOCK_TABLES mode if it's been entered.
+
+ Close all locked tables, free memory, and leave the mode.
+
+ @note This function is a no-op if we're not in LOCK TABLES.
+*/
+
+int
+Locked_tables_list::unlock_locked_tables(THD *thd)
+{
+ int error;
+ DBUG_ASSERT(!thd->in_sub_stmt &&
+ !(thd->state_flags & Open_tables_state::BACKUPS_AVAIL));
+ /*
+ Sic: we must be careful to not close open tables if
+ we're not in LOCK TABLES mode: unlock_locked_tables() is
+ sometimes called implicitly, expecting no effect on
+ open tables, e.g. from begin_trans().
+ */
+ if (thd->locked_tables_mode != LTM_LOCK_TABLES)
+ return 0;
+
+ for (TABLE_LIST *table_list= m_locked_tables;
+ table_list; table_list= table_list->next_global)
+ {
+ /*
+ Clear the position in the list, the TABLE object will be
+ returned to the table cache.
+ */
+ if (table_list->table) // If not closed
+ table_list->table->pos_in_locked_tables= NULL;
+ }
+ thd->leave_locked_tables_mode();
+
+ TRANSACT_TRACKER(clear_trx_state(thd, TX_LOCKED_TABLES));
+
+ DBUG_ASSERT(thd->transaction->stmt.is_empty());
+ error= close_thread_tables(thd);
+
+ /*
+ We rely on the caller to implicitly commit the
+ transaction and release transactional locks.
+ */
+
+ /*
+ After closing tables we can free memory used for storing lock
+ request for metadata locks and TABLE_LIST elements.
+ */
+ reset();
+ return error;
+}
+
+
+/**
+ Remove all meta data locks associated with table and release locked
+ table mode if there is no locked tables anymore
+*/
+
+int
+Locked_tables_list::unlock_locked_table(THD *thd, MDL_ticket *mdl_ticket)
+{
+ /*
+ Ensure we are in locked table mode.
+ As this function is only called on error condition it's better
+ to check this condition here than in the caller.
+ */
+ if (thd->locked_tables_mode != LTM_LOCK_TABLES)
+ return 0;
+
+ if (mdl_ticket)
+ {
+ /*
+ Under LOCK TABLES we may have several instances of table open
+ and locked and therefore have to remove several metadata lock
+ requests associated with them.
+ */
+ thd->mdl_context.release_all_locks_for_name(mdl_ticket);
+ }
+
+ if (thd->lock->table_count == 0)
+ return unlock_locked_tables(thd);
+ return 0;
+}
+
+
+/*
+ Free memory allocated for storing locks
+*/
+
+void Locked_tables_list::reset()
+{
+ free_root(&m_locked_tables_root, MYF(0));
+ m_locked_tables= NULL;
+ m_locked_tables_last= &m_locked_tables;
+ m_reopen_array= NULL;
+ m_locked_tables_count= 0;
+ some_table_marked_for_reopen= 0;
+}
+
+
+/**
+ Unlink a locked table from the locked tables list, either
+ temporarily or permanently.
+
+ @param thd thread handle
+ @param table_list the element of locked tables list.
+ The implementation assumes that this argument
+ points to a TABLE_LIST element linked into
+ the locked tables list. Passing a TABLE_LIST
+ instance that is not part of locked tables
+ list will lead to a crash.
+ @param remove_from_locked_tables
+ TRUE if the table is removed from the list
+ permanently.
+
+ This function is a no-op if we're not under LOCK TABLES.
+
+ @sa Locked_tables_list::reopen_tables()
+*/
+
+
+void Locked_tables_list::unlink_from_list(THD *thd,
+ TABLE_LIST *table_list,
+ bool remove_from_locked_tables)
+{
+ /*
+ If mode is not LTM_LOCK_TABLES, we needn't do anything. Moreover,
+ outside this mode pos_in_locked_tables value is not trustworthy.
+ */
+ if (thd->locked_tables_mode != LTM_LOCK_TABLES &&
+ thd->locked_tables_mode != LTM_PRELOCKED_UNDER_LOCK_TABLES)
+ return;
+
+ /*
+ table_list must be set and point to pos_in_locked_tables of some
+ table.
+ */
+ DBUG_ASSERT(table_list->table->pos_in_locked_tables == table_list);
+
+ /* Clear the pointer, the table will be returned to the table cache. */
+ table_list->table->pos_in_locked_tables= NULL;
+
+ /* Mark the table as closed in the locked tables list. */
+ table_list->table= NULL;
+
+ /*
+ If the table is being dropped or renamed, remove it from
+ the locked tables list (implicitly drop the LOCK TABLES lock
+ on it).
+ */
+ if (remove_from_locked_tables)
+ {
+ *table_list->prev_global= table_list->next_global;
+ if (table_list->next_global == NULL)
+ m_locked_tables_last= table_list->prev_global;
+ else
+ table_list->next_global->prev_global= table_list->prev_global;
+ m_locked_tables_count--;
+ }
+}
+
+/**
+ This is an attempt to recover (somewhat) in case of an error.
+ If we failed to reopen a closed table, let's unlink it from the
+ list and forget about it. From a user perspective that would look
+ as if the server "lost" the lock on one of the locked tables.
+
+ @note This function is a no-op if we're not under LOCK TABLES.
+*/
+
+void Locked_tables_list::
+unlink_all_closed_tables(THD *thd, MYSQL_LOCK *lock, size_t reopen_count)
+{
+ /* If we managed to take a lock, unlock tables and free the lock. */
+ if (lock)
+ mysql_unlock_tables(thd, lock);
+ /*
+ If a failure happened in reopen_tables(), we may have succeeded
+ reopening some tables, but not all.
+ This works when the connection was killed in mysql_lock_tables().
+ */
+ if (reopen_count)
+ {
+ while (reopen_count--)
+ {
+ /*
+ When closing the table, we must remove it
+ from thd->open_tables list.
+ We rely on the fact that open_table() that was used
+ in reopen_tables() always links the opened table
+ to the beginning of the open_tables list.
+ */
+ DBUG_ASSERT(thd->open_tables == m_reopen_array[reopen_count]->table);
+
+ thd->open_tables->pos_in_locked_tables->table= NULL;
+ thd->open_tables->pos_in_locked_tables= NULL;
+
+ close_thread_table(thd, &thd->open_tables);
+ }
+ }
+ /* Exclude all closed tables from the LOCK TABLES list. */
+ for (TABLE_LIST *table_list= m_locked_tables; table_list; table_list=
+ table_list->next_global)
+ {
+ if (table_list->table == NULL)
+ {
+ /* Unlink from list. */
+ *table_list->prev_global= table_list->next_global;
+ if (table_list->next_global == NULL)
+ m_locked_tables_last= table_list->prev_global;
+ else
+ table_list->next_global->prev_global= table_list->prev_global;
+ m_locked_tables_count--;
+ }
+ }
+
+ /* If no tables left, do an automatic UNLOCK TABLES */
+ if (thd->lock && thd->lock->table_count == 0)
+ {
+ /*
+ We have to rollback any open transactions here.
+ This is required in the case where the server has been killed
+ but some transations are still open (as part of locked tables).
+ If we don't do this, we will get an assert in unlock_locked_tables().
+ */
+ ha_rollback_trans(thd, FALSE);
+ ha_rollback_trans(thd, TRUE);
+ unlock_locked_tables(thd);
+ }
+}
+
+
+/*
+ Mark all instances of the table to be reopened
+
+ This is only needed when LOCK TABLES is active
+*/
+
+void Locked_tables_list::mark_table_for_reopen(THD *thd, TABLE *table)
+{
+ TABLE_SHARE *share= table->s;
+
+ for (TABLE_LIST *table_list= m_locked_tables;
+ table_list; table_list= table_list->next_global)
+ {
+ if (table_list->table->s == share)
+ table_list->table->internal_set_needs_reopen(true);
+ }
+ /* This is needed in the case where lock tables where not used */
+ table->internal_set_needs_reopen(true);
+ some_table_marked_for_reopen= 1;
+}
+
+
+/**
+ Reopen the tables locked with LOCK TABLES and temporarily closed
+ by a DDL statement or FLUSH TABLES.
+
+ @param need_reopen If set, reopen open tables that are marked with
+ for reopen.
+ If not set, reopen tables that where closed.
+
+ @note This function is a no-op if we're not under LOCK TABLES.
+
+ @return TRUE if an error reopening the tables. May happen in
+ case of some fatal system error only, e.g. a disk
+ corruption, out of memory or a serious bug in the
+ locking.
+*/
+
+bool
+Locked_tables_list::reopen_tables(THD *thd, bool need_reopen)
+{
+ Open_table_context ot_ctx(thd, MYSQL_OPEN_REOPEN);
+ uint reopen_count= 0;
+ MYSQL_LOCK *lock;
+ MYSQL_LOCK *merged_lock;
+ DBUG_ENTER("Locked_tables_list::reopen_tables");
+
+ DBUG_ASSERT(some_table_marked_for_reopen || !need_reopen);
+
+
+ /* Reset flag that some table was marked for reopen */
+ if (need_reopen)
+ some_table_marked_for_reopen= 0;
+
+ for (TABLE_LIST *table_list= m_locked_tables;
+ table_list; table_list= table_list->next_global)
+ {
+ if (need_reopen)
+ {
+ if (!table_list->table || !table_list->table->needs_reopen())
+ continue;
+ for (TABLE **prev= &thd->open_tables; *prev; prev= &(*prev)->next)
+ {
+ if (*prev == table_list->table)
+ {
+ thd->locked_tables_list.unlink_from_list(thd, table_list, false);
+ mysql_lock_remove(thd, thd->lock, *prev);
+ (*prev)->file->extra(HA_EXTRA_PREPARE_FOR_FORCED_CLOSE);
+ close_thread_table(thd, prev);
+ break;
+ }
+ }
+ DBUG_ASSERT(table_list->table == NULL);
+ }
+ else
+ {
+ if (table_list->table) /* The table was not closed */
+ continue;
+ }
+
+ DBUG_ASSERT(reopen_count < m_locked_tables_count);
+ m_reopen_array[reopen_count++]= table_list;
+ }
+ if (reopen_count)
+ {
+ TABLE **tables= (TABLE**) my_alloca(reopen_count * sizeof(TABLE*));
+
+ for (uint i= 0 ; i < reopen_count ; i++)
+ {
+ TABLE_LIST *table_list= m_reopen_array[i];
+ /* Links into thd->open_tables upon success */
+ if (open_table(thd, table_list, &ot_ctx))
+ {
+ unlink_all_closed_tables(thd, 0, i);
+ my_afree((void*) tables);
+ DBUG_RETURN(TRUE);
+ }
+ tables[i]= table_list->table;
+ table_list->table->pos_in_locked_tables= table_list;
+ /* See also the comment on lock type in init_locked_tables(). */
+ table_list->table->reginfo.lock_type= table_list->lock_type;
+ }
+
+ thd->in_lock_tables= 1;
+ /*
+ We re-lock all tables with mysql_lock_tables() at once rather
+ than locking one table at a time because of the case
+ reported in Bug#45035: when the same table is present
+ in the list many times, thr_lock.c fails to grant READ lock
+ on a table that is already locked by WRITE lock, even if
+ WRITE lock is taken by the same thread. If READ and WRITE
+ lock are passed to thr_lock.c in the same list, everything
+ works fine. Patching legacy code of thr_lock.c is risking to
+ break something else.
+ */
+ lock= mysql_lock_tables(thd, tables, reopen_count,
+ MYSQL_OPEN_REOPEN | MYSQL_LOCK_USE_MALLOC);
+ thd->in_lock_tables= 0;
+ if (lock == NULL || (merged_lock=
+ mysql_lock_merge(thd->lock, lock)) == NULL)
+ {
+ unlink_all_closed_tables(thd, lock, reopen_count);
+ if (! thd->killed)
+ my_error(ER_LOCK_DEADLOCK, MYF(0));
+ my_afree((void*) tables);
+ DBUG_RETURN(TRUE);
+ }
+ thd->lock= merged_lock;
+ my_afree((void*) tables);
+ }
+ DBUG_RETURN(FALSE);
+}
+
+/**
+ Add back a locked table to the locked list that we just removed from it.
+ This is needed in CREATE OR REPLACE TABLE where we are dropping, creating
+ and re-opening a locked table.
+
+ @return 0 0k
+ @return 1 error
+*/
+
+bool Locked_tables_list::restore_lock(THD *thd, TABLE_LIST *dst_table_list,
+ TABLE *table, MYSQL_LOCK *lock)
+{
+ MYSQL_LOCK *merged_lock;
+ DBUG_ENTER("restore_lock");
+ DBUG_ASSERT(!strcmp(dst_table_list->table_name.str, table->s->table_name.str));
+
+ /* Ensure we have the memory to add the table back */
+ if (!(merged_lock= mysql_lock_merge(thd->lock, lock)))
+ DBUG_RETURN(1);
+ thd->lock= merged_lock;
+
+ /* Link to the new table */
+ dst_table_list->table= table;
+ /*
+ The lock type may have changed (normally it should not as create
+ table will lock the table in write mode
+ */
+ dst_table_list->lock_type= table->reginfo.lock_type;
+ table->pos_in_locked_tables= dst_table_list;
+
+ add_back_last_deleted_lock(dst_table_list);
+
+ table->mdl_ticket->downgrade_lock(table->reginfo.lock_type >=
+ TL_WRITE_ALLOW_WRITE ?
+ MDL_SHARED_NO_READ_WRITE :
+ MDL_SHARED_READ);
+
+ DBUG_RETURN(0);
+}
+
+/*
+ Add back the last deleted lock structure.
+ This should be followed by a call to reopen_tables() to
+ open the table.
+*/
+
+void Locked_tables_list::add_back_last_deleted_lock(TABLE_LIST *dst_table_list)
+{
+ /* Link the lock back in the locked tables list */
+ dst_table_list->prev_global= m_locked_tables_last;
+ *m_locked_tables_last= dst_table_list;
+ m_locked_tables_last= &dst_table_list->next_global;
+ dst_table_list->next_global= 0;
+ m_locked_tables_count++;
+}
+
+
+#ifndef DBUG_OFF
+/* Cause a spurious statement reprepare for debug purposes. */
+static bool inject_reprepare(THD *thd)
+{
+ if (thd->m_reprepare_observer && thd->stmt_arena->is_reprepared == FALSE)
+ {
+ thd->m_reprepare_observer->report_error(thd);
+ return TRUE;
+ }
+
+ return FALSE;
+}
+#endif
+
+/**
+ Compare metadata versions of an element obtained from the table
+ definition cache and its corresponding node in the parse tree.
+
+ @details If the new and the old values mismatch, invoke
+ Metadata_version_observer.
+ At prepared statement prepare, all TABLE_LIST version values are
+ NULL and we always have a mismatch. But there is no observer set
+ in THD, and therefore no error is reported. Instead, we update
+ the value in the parse tree, effectively recording the original
+ version.
+ At prepared statement execute, an observer may be installed. If
+ there is a version mismatch, we push an error and return TRUE.
+
+ For conventional execution (no prepared statements), the
+ observer is never installed.
+
+ @sa Execute_observer
+ @sa check_prepared_statement() to see cases when an observer is installed
+ @sa TABLE_LIST::is_table_ref_id_equal()
+ @sa TABLE_SHARE::get_table_ref_id()
+
+ @param[in] thd used to report errors
+ @param[in,out] tables TABLE_LIST instance created by the parser
+ Metadata version information in this object
+ is updated upon success.
+ @param[in] table_share an element from the table definition cache
+
+ @retval TRUE an error, which has been reported
+ @retval FALSE success, version in TABLE_LIST has been updated
+*/
+
+static bool
+check_and_update_table_version(THD *thd,
+ TABLE_LIST *tables, TABLE_SHARE *table_share)
+{
+ if (! tables->is_table_ref_id_equal(table_share))
+ {
+ if (thd->m_reprepare_observer &&
+ thd->m_reprepare_observer->report_error(thd))
+ {
+ /*
+ Version of the table share is different from the
+ previous execution of the prepared statement, and it is
+ unacceptable for this SQLCOM. Error has been reported.
+ */
+ DBUG_ASSERT(thd->is_error());
+ return TRUE;
+ }
+ /* Always maintain the latest version and type */
+ tables->set_table_ref_id(table_share);
+ }
+
+ DBUG_EXECUTE_IF("reprepare_each_statement", return inject_reprepare(thd););
+ return FALSE;
+}
+
+
+/**
+ Compares versions of a stored routine obtained from the sp cache
+ and the version used at prepare.
+
+ @details If the new and the old values mismatch, invoke
+ Metadata_version_observer.
+ At prepared statement prepare, all Sroutine_hash_entry version values
+ are NULL and we always have a mismatch. But there is no observer set
+ in THD, and therefore no error is reported. Instead, we update
+ the value in Sroutine_hash_entry, effectively recording the original
+ version.
+ At prepared statement execute, an observer may be installed. If
+ there is a version mismatch, we push an error and return TRUE.
+
+ For conventional execution (no prepared statements), the
+ observer is never installed.
+
+ @param[in] thd used to report errors
+ @param[in/out] rt pointer to stored routine entry in the
+ parse tree
+ @param[in] sp pointer to stored routine cache entry.
+ Can be NULL if there is no such routine.
+ @retval TRUE an error, which has been reported
+ @retval FALSE success, version in Sroutine_hash_entry has been updated
+*/
+
+static bool
+check_and_update_routine_version(THD *thd, Sroutine_hash_entry *rt,
+ sp_head *sp)
+{
+ ulong spc_version= sp_cache_version();
+ /* sp is NULL if there is no such routine. */
+ ulong version= sp ? sp->sp_cache_version() : spc_version;
+ /*
+ If the version in the parse tree is stale,
+ or the version in the cache is stale and sp is not used,
+ we need to reprepare.
+ Sic: version != spc_version <--> sp is not NULL.
+ */
+ if (rt->m_sp_cache_version != version ||
+ (version != spc_version && !sp->is_invoked()))
+ {
+ if (thd->m_reprepare_observer &&
+ thd->m_reprepare_observer->report_error(thd))
+ {
+ /*
+ Version of the sp cache is different from the
+ previous execution of the prepared statement, and it is
+ unacceptable for this SQLCOM. Error has been reported.
+ */
+ DBUG_ASSERT(thd->is_error());
+ return TRUE;
+ }
+ /* Always maintain the latest cache version. */
+ rt->m_sp_cache_version= version;
+ }
+ return FALSE;
+}
+
+
+/**
+ Open view by getting its definition from disk (and table cache in future).
+
+ @param thd Thread handle
+ @param table_list TABLE_LIST with db, table_name & belong_to_view
+ @param flags Flags which modify how we open the view
+
+ @todo This function is needed for special handling of views under
+ LOCK TABLES. We probably should get rid of it in long term.
+
+ @return FALSE if success, TRUE - otherwise.
+*/
+
+bool tdc_open_view(THD *thd, TABLE_LIST *table_list, uint flags)
+{
+ TABLE not_used;
+ TABLE_SHARE *share;
+ bool err= TRUE;
+
+ if (!(share= tdc_acquire_share(thd, table_list, GTS_VIEW)))
+ return TRUE;
+
+ DBUG_ASSERT(share->is_view);
+
+ if (flags & CHECK_METADATA_VERSION)
+ {
+ /*
+ Check TABLE_SHARE-version of view only if we have been instructed to do
+ so. We do not need to check the version if we're executing CREATE VIEW or
+ ALTER VIEW statements.
+
+ In the future, this functionality should be moved out from
+ tdc_open_view(), and tdc_open_view() should became a part of a clean
+ table-definition-cache interface.
+ */
+ if (check_and_update_table_version(thd, table_list, share))
+ goto ret;
+ }
+
+ err= mysql_make_view(thd, share, table_list, (flags & OPEN_VIEW_NO_PARSE));
+ret:
+ tdc_release_share(share);
+
+ return err;
+}
+
+
+/**
+ Finalize the process of TABLE creation by loading table triggers
+ and taking action if a HEAP table content was emptied implicitly.
+*/
+
+static bool open_table_entry_fini(THD *thd, TABLE_SHARE *share, TABLE *entry)
+{
+ if (Table_triggers_list::check_n_load(thd, &share->db,
+ &share->table_name, entry, 0))
+ return TRUE;
+
+ /*
+ If we are here, there was no fatal error (but error may be still
+ unitialized).
+ */
+ if (unlikely(entry->file->implicit_emptied))
+ {
+ entry->file->implicit_emptied= 0;
+ if (mysql_bin_log.is_open())
+ {
+ char query_buf[2*FN_REFLEN + 21];
+ String query(query_buf, sizeof(query_buf), system_charset_info);
+
+ query.length(0);
+ query.append("DELETE FROM ");
+ append_identifier(thd, &query, &share->db);
+ query.append(".");
+ append_identifier(thd, &query, &share->table_name);
+
+ /*
+ we bypass thd->binlog_query() here,
+ as it does a lot of extra work, that is simply wrong in this case
+ */
+ Query_log_event qinfo(thd, query.ptr(), query.length(),
+ FALSE, TRUE, TRUE, 0);
+ if (mysql_bin_log.write(&qinfo))
+ return TRUE;
+ }
+ }
+ return FALSE;
+}
+
+
+/**
+ Auxiliary routine which is used for performing automatical table repair.
+*/
+
+static bool auto_repair_table(THD *thd, TABLE_LIST *table_list)
+{
+ TABLE_SHARE *share;
+ TABLE entry;
+ bool result= TRUE;
+
+ thd->clear_error();
+
+ if (!(share= tdc_acquire_share(thd, table_list, GTS_TABLE)))
+ return result;
+
+ DBUG_ASSERT(! share->is_view);
+
+ if (open_table_from_share(thd, share, &table_list->alias,
+ HA_OPEN_KEYFILE | HA_TRY_READ_ONLY,
+ EXTRA_RECORD,
+ ha_open_options | HA_OPEN_FOR_REPAIR,
+ &entry, FALSE) || ! entry.file ||
+ (entry.file->is_crashed() && entry.file->ha_check_and_repair(thd)))
+ {
+ /* Give right error message */
+ thd->clear_error();
+ my_error(ER_NOT_KEYFILE, MYF(0), share->table_name.str);
+ sql_print_error("Couldn't repair table: %s.%s", share->db.str,
+ share->table_name.str);
+ if (entry.file)
+ closefrm(&entry);
+ }
+ else
+ {
+ thd->clear_error(); // Clear error message
+ closefrm(&entry);
+ result= FALSE;
+ }
+
+ tdc_remove_referenced_share(thd, share);
+ return result;
+}
+
+
+/** Open_table_context */
+
+Open_table_context::Open_table_context(THD *thd, uint flags)
+ :m_thd(thd),
+ m_failed_table(NULL),
+ m_start_of_statement_svp(thd->mdl_context.mdl_savepoint()),
+ m_timeout(flags & MYSQL_LOCK_IGNORE_TIMEOUT ?
+ LONG_TIMEOUT : thd->variables.lock_wait_timeout),
+ m_flags(flags),
+ m_action(OT_NO_ACTION),
+ m_has_locks(thd->mdl_context.has_locks()),
+ m_has_protection_against_grl(0)
+{}
+
+
+/**
+ Check if we can back-off and set back off action if we can.
+ Otherwise report and return error.
+
+ @retval TRUE if back-off is impossible.
+ @retval FALSE if we can back off. Back off action has been set.
+*/
+
+bool
+Open_table_context::
+request_backoff_action(enum_open_table_action action_arg,
+ TABLE_LIST *table)
+{
+ /*
+ A back off action may be one of three kinds:
+
+ * We met a broken table that needs repair, or a table that
+ is not present on this MySQL server and needs re-discovery.
+ To perform the action, we need an exclusive metadata lock on
+ the table. Acquiring X lock while holding other shared
+ locks can easily lead to deadlocks. We rely on MDL deadlock
+ detector to discover them. If this is a multi-statement
+ transaction that holds metadata locks for completed statements,
+ we should keep these locks after discovery/repair.
+ The action type in this case is OT_DISCOVER or OT_REPAIR.
+ * Our attempt to acquire an MDL lock lead to a deadlock,
+ detected by the MDL deadlock detector. The current
+ session was chosen a victim. If this is a multi-statement
+ transaction that holds metadata locks taken by completed
+ statements, restarting locking for the current statement
+ may lead to a livelock. Releasing locks of completed
+ statements can not be done as will lead to violation
+ of ACID. Thus, again, if m_has_locks is set,
+ we report an error. Otherwise, when there are no metadata
+ locks other than which belong to this statement, we can
+ try to recover from error by releasing all locks and
+ restarting the pre-locking.
+ Similarly, a deadlock error can occur when the
+ pre-locking process met a TABLE_SHARE that is being
+ flushed, and unsuccessfully waited for the flush to
+ complete. A deadlock in this case can happen, e.g.,
+ when our session is holding a metadata lock that
+ is being waited on by a session which is using
+ the table which is being flushed. The only way
+ to recover from this error is, again, to close all
+ open tables, release all locks, and retry pre-locking.
+ Action type name is OT_REOPEN_TABLES. Re-trying
+ while holding some locks may lead to a livelock,
+ and thus we don't do it.
+ * Finally, this session has open TABLEs from different
+ "generations" of the table cache. This can happen, e.g.,
+ when, after this session has successfully opened one
+ table used for a statement, FLUSH TABLES interfered and
+ expelled another table used in it. FLUSH TABLES then
+ blocks and waits on the table already opened by this
+ statement.
+ We detect this situation by ensuring that table cache
+ version of all tables used in a statement is the same.
+ If it isn't, all tables needs to be reopened.
+ Note, that we can always perform a reopen in this case,
+ even if we already have metadata locks, since we don't
+ keep tables open between statements and a livelock
+ is not possible.
+ */
+ if (action_arg == OT_BACKOFF_AND_RETRY && m_has_locks)
+ {
+ my_error(ER_LOCK_DEADLOCK, MYF(0));
+ m_thd->mark_transaction_to_rollback(true);
+ return TRUE;
+ }
+ /*
+ If auto-repair or discovery are requested, a pointer to table
+ list element must be provided.
+ */
+ if (table)
+ {
+ DBUG_ASSERT(action_arg == OT_DISCOVER || action_arg == OT_REPAIR);
+ m_failed_table= (TABLE_LIST*) m_thd->alloc(sizeof(TABLE_LIST));
+ if (m_failed_table == NULL)
+ return TRUE;
+ m_failed_table->init_one_table(&table->db, &table->table_name, &table->alias, TL_WRITE);
+ m_failed_table->open_strategy= table->open_strategy;
+ m_failed_table->mdl_request.set_type(MDL_EXCLUSIVE);
+ }
+ m_action= action_arg;
+ return FALSE;
+}
+
+
+/**
+ An error handler to mark transaction to rollback on DEADLOCK error
+ during DISCOVER / REPAIR.
+*/
+class MDL_deadlock_discovery_repair_handler : public Internal_error_handler
+{
+public:
+ virtual bool handle_condition(THD *thd,
+ uint sql_errno,
+ const char* sqlstate,
+ Sql_condition::enum_warning_level *level,
+ const char* msg,
+ Sql_condition ** cond_hdl)
+ {
+ if (sql_errno == ER_LOCK_DEADLOCK)
+ {
+ thd->mark_transaction_to_rollback(true);
+ }
+ /*
+ We have marked this transaction to rollback. Return false to allow
+ error to be reported or handled by other handlers.
+ */
+ return false;
+ }
+};
+
+/**
+ Recover from failed attempt of open table by performing requested action.
+
+ @pre This function should be called only with "action" != OT_NO_ACTION
+ and after having called @sa close_tables_for_reopen().
+
+ @retval FALSE - Success. One should try to open tables once again.
+ @retval TRUE - Error
+*/
+
+bool
+Open_table_context::recover_from_failed_open()
+{
+ bool result= FALSE;
+ MDL_deadlock_discovery_repair_handler handler;
+ /*
+ Install error handler to mark transaction to rollback on DEADLOCK error.
+ */
+ m_thd->push_internal_handler(&handler);
+
+ /* Execute the action. */
+ switch (m_action)
+ {
+ case OT_BACKOFF_AND_RETRY:
+ case OT_REOPEN_TABLES:
+ break;
+ case OT_DISCOVER:
+ case OT_REPAIR:
+ if ((result= lock_table_names(m_thd, m_thd->lex->create_info,
+ m_failed_table, NULL,
+ get_timeout(), 0)))
+ break;
+
+ tdc_remove_table(m_thd, m_failed_table->db.str,
+ m_failed_table->table_name.str);
+
+ switch (m_action)
+ {
+ case OT_DISCOVER:
+ {
+ m_thd->get_stmt_da()->clear_warning_info(m_thd->query_id);
+ m_thd->clear_error(); // Clear error message
+
+ No_such_table_error_handler no_such_table_handler;
+ bool open_if_exists= m_failed_table->open_strategy == TABLE_LIST::OPEN_IF_EXISTS;
+
+ if (open_if_exists)
+ m_thd->push_internal_handler(&no_such_table_handler);
+
+ result= !tdc_acquire_share(m_thd, m_failed_table,
+ GTS_TABLE | GTS_FORCE_DISCOVERY | GTS_NOLOCK);
+ if (open_if_exists)
+ {
+ m_thd->pop_internal_handler();
+ if (result && no_such_table_handler.safely_trapped_errors())
+ result= FALSE;
+ }
+ break;
+ }
+ case OT_REPAIR:
+ result= auto_repair_table(m_thd, m_failed_table);
+ break;
+ case OT_BACKOFF_AND_RETRY:
+ case OT_REOPEN_TABLES:
+ case OT_NO_ACTION:
+ DBUG_ASSERT(0);
+ }
+ /*
+ Rollback to start of the current statement to release exclusive lock
+ on table which was discovered but preserve locks from previous statements
+ in current transaction.
+ */
+ m_thd->mdl_context.rollback_to_savepoint(start_of_statement_svp());
+ break;
+ case OT_NO_ACTION:
+ DBUG_ASSERT(0);
+ }
+ m_thd->pop_internal_handler();
+ /*
+ Reset the pointers to conflicting MDL request and the
+ TABLE_LIST element, set when we need auto-discovery or repair,
+ for safety.
+ */
+ m_failed_table= NULL;
+ /*
+ Reset flag indicating that we have already acquired protection
+ against GRL. It is no longer valid as the corresponding lock was
+ released by close_tables_for_reopen().
+ */
+ m_has_protection_against_grl= 0;
+ /* Prepare for possible another back-off. */
+ m_action= OT_NO_ACTION;
+ return result;
+}
+
+
+/*
+ Return a appropriate read lock type given a table object.
+
+ @param thd Thread context
+ @param prelocking_ctx Prelocking context.
+ @param table_list Table list element for table to be locked.
+ @param routine_modifies_data
+ Some routine that is invoked by statement
+ modifies data.
+
+ @remark Due to a statement-based replication limitation, statements such as
+ INSERT INTO .. SELECT FROM .. and CREATE TABLE .. SELECT FROM need
+ to grab a TL_READ_NO_INSERT lock on the source table in order to
+ prevent the replication of a concurrent statement that modifies the
+ source table. If such a statement gets applied on the slave before
+ the INSERT .. SELECT statement finishes, data on the master could
+ differ from data on the slave and end-up with a discrepancy between
+ the binary log and table state.
+ This also applies to SELECT/SET/DO statements which use stored
+ functions. Calls to such functions are going to be logged as a
+ whole and thus should be serialized against concurrent changes
+ to tables used by those functions. This is avoided when functions
+ do not modify data but only read it, since in this case nothing is
+ written to the binary log. Argument routine_modifies_data
+ denotes the same. So effectively, if the statement is not a
+ update query and routine_modifies_data is false, then
+ prelocking_placeholder does not take importance.
+
+ Furthermore, this does not apply to I_S and log tables as it's
+ always unsafe to replicate such tables under statement-based
+ replication as the table on the slave might contain other data
+ (ie: general_log is enabled on the slave). The statement will
+ be marked as unsafe for SBR in decide_logging_format().
+ @remark Note that even in prelocked mode it is important to correctly
+ determine lock type value. In this mode lock type is passed to
+ handler::start_stmt() method and can be used by storage engine,
+ for example, to determine what kind of row locks it should acquire
+ when reading data from the table.
+*/
+
+thr_lock_type read_lock_type_for_table(THD *thd,
+ Query_tables_list *prelocking_ctx,
+ TABLE_LIST *table_list,
+ bool routine_modifies_data)
+{
+ /*
+ In cases when this function is called for a sub-statement executed in
+ prelocked mode we can't rely on OPTION_BIN_LOG flag in THD::options
+ bitmap to determine that binary logging is turned on as this bit can
+ be cleared before executing sub-statement. So instead we have to look
+ at THD::variables::sql_log_bin member.
+ */
+ bool log_on= mysql_bin_log.is_open() && thd->variables.sql_log_bin;
+ if ((log_on == FALSE) || (thd->wsrep_binlog_format() == BINLOG_FORMAT_ROW) ||
+ (table_list->table->s->table_category == TABLE_CATEGORY_LOG) ||
+ (table_list->table->s->table_category == TABLE_CATEGORY_PERFORMANCE) ||
+ !(is_update_query(prelocking_ctx->sql_command) ||
+ (routine_modifies_data && table_list->prelocking_placeholder) ||
+ (thd->locked_tables_mode > LTM_LOCK_TABLES)))
+ return TL_READ;
+ else
+ return TL_READ_NO_INSERT;
+}
+
+
+/*
+ Extend the prelocking set with tables and routines used by a routine.
+
+ @param[in] thd Thread context.
+ @param[in] rt Element of prelocking set to be processed.
+ @param[in] ot_ctx Context of open_table used to recover from
+ locking failures.
+ @retval false Success.
+ @retval true Failure (Conflicting metadata lock, OOM, other errors).
+*/
+static bool
+sp_acquire_mdl(THD *thd, Sroutine_hash_entry *rt, Open_table_context *ot_ctx)
+{
+ DBUG_ENTER("sp_acquire_mdl");
+ /*
+ Since we acquire only shared lock on routines we don't
+ need to care about global intention exclusive locks.
+ */
+ DBUG_ASSERT(rt->mdl_request.type == MDL_SHARED);
+
+ /*
+ Waiting for a conflicting metadata lock to go away may
+ lead to a deadlock, detected by MDL subsystem.
+ If possible, we try to resolve such deadlocks by releasing all
+ metadata locks and restarting the pre-locking process.
+ To prevent the error from polluting the diagnostics area
+ in case of successful resolution, install a special error
+ handler for ER_LOCK_DEADLOCK error.
+ */
+ MDL_deadlock_handler mdl_deadlock_handler(ot_ctx);
+
+ thd->push_internal_handler(&mdl_deadlock_handler);
+ bool result= thd->mdl_context.acquire_lock(&rt->mdl_request,
+ ot_ctx->get_timeout());
+ thd->pop_internal_handler();
+
+ DBUG_RETURN(result);
+}
+
+
+/*
+ Handle element of prelocking set other than table. E.g. cache routine
+ and, if prelocking strategy prescribes so, extend the prelocking set
+ with tables and routines used by it.
+
+ @param[in] thd Thread context.
+ @param[in] prelocking_ctx Prelocking context.
+ @param[in] rt Element of prelocking set to be processed.
+ @param[in] prelocking_strategy Strategy which specifies how the
+ prelocking set should be extended when
+ one of its elements is processed.
+ @param[in] has_prelocking_list Indicates that prelocking set/list for
+ this statement has already been built.
+ @param[in] ot_ctx Context of open_table used to recover from
+ locking failures.
+ @param[out] need_prelocking Set to TRUE if it was detected that this
+ statement will require prelocked mode for
+ its execution, not touched otherwise.
+ @param[out] routine_modifies_data Set to TRUE if it was detected that this
+ routine does modify table data.
+
+ @retval FALSE Success.
+ @retval TRUE Failure (Conflicting metadata lock, OOM, other errors).
+*/
+
+static bool
+open_and_process_routine(THD *thd, Query_tables_list *prelocking_ctx,
+ Sroutine_hash_entry *rt,
+ Prelocking_strategy *prelocking_strategy,
+ bool has_prelocking_list,
+ Open_table_context *ot_ctx,
+ bool *need_prelocking, bool *routine_modifies_data)
+{
+ MDL_key::enum_mdl_namespace mdl_type= rt->mdl_request.key.mdl_namespace();
+ DBUG_ENTER("open_and_process_routine");
+
+ *routine_modifies_data= false;
+
+ switch (mdl_type)
+ {
+ case MDL_key::PACKAGE_BODY:
+ DBUG_ASSERT(rt != (Sroutine_hash_entry*)prelocking_ctx->sroutines_list.first);
+ /*
+ No need to cache the package body itself.
+ It gets cached during open_and_process_routine()
+ for the first used package routine. See the package related code
+ in the "case" below.
+ */
+ if (sp_acquire_mdl(thd, rt, ot_ctx))
+ DBUG_RETURN(TRUE);
+ break;
+ case MDL_key::FUNCTION:
+ case MDL_key::PROCEDURE:
+ {
+ sp_head *sp;
+ /*
+ Try to get MDL lock on the routine.
+ Note that we do not take locks on top-level CALLs as this can
+ lead to a deadlock. Not locking top-level CALLs does not break
+ the binlog as only the statements in the called procedure show
+ up there, not the CALL itself.
+ */
+ if (rt != (Sroutine_hash_entry*)prelocking_ctx->sroutines_list.first ||
+ mdl_type != MDL_key::PROCEDURE)
+ {
+ /*
+ TODO: If this is a package routine, we should not put MDL
+ TODO: on the routine itself. We should put only the package MDL.
+ */
+ if (sp_acquire_mdl(thd, rt, ot_ctx))
+ DBUG_RETURN(TRUE);
+
+ /* Ensures the routine is up-to-date and cached, if exists. */
+ if (rt->sp_cache_routine(thd, has_prelocking_list, &sp))
+ DBUG_RETURN(TRUE);
+
+ /* Remember the version of the routine in the parse tree. */
+ if (check_and_update_routine_version(thd, rt, sp))
+ DBUG_RETURN(TRUE);
+
+ /* 'sp' is NULL when there is no such routine. */
+ if (sp)
+ {
+ *routine_modifies_data= sp->modifies_data();
+
+ if (!has_prelocking_list)
+ {
+ prelocking_strategy->handle_routine(thd, prelocking_ctx, rt, sp,
+ need_prelocking);
+ if (sp->m_parent)
+ {
+ /*
+ If it's a package routine, we need also to handle the
+ package body, as its initialization section can use
+ some tables and routine calls.
+ TODO: Only package public routines actually need this.
+ TODO: Skip package body handling for private routines.
+ */
+ *routine_modifies_data|= sp->m_parent->modifies_data();
+ prelocking_strategy->handle_routine(thd, prelocking_ctx, rt,
+ sp->m_parent,
+ need_prelocking);
+ }
+ }
+ }
+ }
+ else
+ {
+ /*
+ If it's a top level call, just make sure we have a recent
+ version of the routine, if it exists.
+ Validating routine version is unnecessary, since CALL
+ does not affect the prepared statement prelocked list.
+ */
+ if (rt->sp_cache_routine(thd, false, &sp))
+ DBUG_RETURN(TRUE);
+ }
+ }
+ break;
+ case MDL_key::TRIGGER:
+ /**
+ We add trigger entries to lex->sroutines_list, but we don't
+ load them here. The trigger entry is only used when building
+ a transitive closure of objects used in a statement, to avoid
+ adding to this closure objects that are used in the trigger more
+ than once.
+ E.g. if a trigger trg refers to table t2, and the trigger table t1
+ is used multiple times in the statement (say, because it's used in
+ function f1() twice), we will only add t2 once to the list of
+ tables to prelock.
+
+ We don't take metadata locks on triggers either: they are protected
+ by a respective lock on the table, on which the trigger is defined.
+
+ The only two cases which give "trouble" are SHOW CREATE TRIGGER
+ and DROP TRIGGER statements. For these, statement syntax doesn't
+ specify the table on which this trigger is defined, so we have
+ to make a "dirty" read in the data dictionary to find out the
+ table name. Once we discover the table name, we take a metadata
+ lock on it, and this protects all trigger operations.
+ Of course the table, in theory, may disappear between the dirty
+ read and metadata lock acquisition, but in that case we just return
+ a run-time error.
+
+ Grammar of other trigger DDL statements (CREATE, DROP) requires
+ the table to be specified explicitly, so we use the table metadata
+ lock to protect trigger metadata in these statements. Similarly, in
+ DML we always use triggers together with their tables, and thus don't
+ need to take separate metadata locks on them.
+ */
+ break;
+ default:
+ /* Impossible type value. */
+ DBUG_ASSERT(0);
+ }
+ DBUG_RETURN(FALSE);
+}
+
+/*
+ If we are not already in prelocked mode and extended table list is not
+ yet built we might have to build the prelocking set for this statement.
+
+ Since currently no prelocking strategy prescribes doing anything for
+ tables which are only read, we do below checks only if table is going
+ to be changed.
+*/
+bool extend_table_list(THD *thd, TABLE_LIST *tables,
+ Prelocking_strategy *prelocking_strategy,
+ bool has_prelocking_list)
+{
+ bool error= false;
+ LEX *lex= thd->lex;
+ bool maybe_need_prelocking=
+ (tables->updating && tables->lock_type >= TL_WRITE_ALLOW_WRITE)
+ || thd->lex->default_used;
+
+ if (thd->locked_tables_mode <= LTM_LOCK_TABLES &&
+ ! has_prelocking_list && maybe_need_prelocking)
+ {
+ bool need_prelocking= FALSE;
+ TABLE_LIST **save_query_tables_last= lex->query_tables_last;
+ /*
+ Extend statement's table list and the prelocking set with
+ tables and routines according to the current prelocking
+ strategy.
+
+ For example, for DML statements we need to add tables and routines
+ used by triggers which are going to be invoked for this element of
+ table list and also add tables required for handling of foreign keys.
+ */
+ error= prelocking_strategy->handle_table(thd, lex, tables,
+ &need_prelocking);
+
+ if (need_prelocking && ! lex->requires_prelocking())
+ lex->mark_as_requiring_prelocking(save_query_tables_last);
+ }
+ return error;
+}
+
+
+/**
+ Handle table list element by obtaining metadata lock, opening table or view
+ and, if prelocking strategy prescribes so, extending the prelocking set with
+ tables and routines used by it.
+
+ @param[in] thd Thread context.
+ @param[in] lex LEX structure for statement.
+ @param[in] tables Table list element to be processed.
+ @param[in,out] counter Number of tables which are open.
+ @param[in] flags Bitmap of flags to modify how the tables
+ will be open, see open_table() description
+ for details.
+ @param[in] prelocking_strategy Strategy which specifies how the
+ prelocking set should be extended
+ when table or view is processed.
+ @param[in] has_prelocking_list Indicates that prelocking set/list for
+ this statement has already been built.
+ @param[in] ot_ctx Context used to recover from a failed
+ open_table() attempt.
+
+ @retval FALSE Success.
+ @retval TRUE Error, reported unless there is a chance to recover from it.
+*/
+
+static bool
+open_and_process_table(THD *thd, TABLE_LIST *tables, uint *counter, uint flags,
+ Prelocking_strategy *prelocking_strategy,
+ bool has_prelocking_list, Open_table_context *ot_ctx)
+{
+ bool error= FALSE;
+ bool safe_to_ignore_table= FALSE;
+ LEX *lex= thd->lex;
+ DBUG_ENTER("open_and_process_table");
+ DEBUG_SYNC(thd, "open_and_process_table");
+
+ /*
+ Ignore placeholders for derived tables. After derived tables
+ processing, link to created temporary table will be put here.
+ If this is derived table for view then we still want to process
+ routines used by this view.
+ */
+ if (tables->derived)
+ {
+ if (!tables->view)
+ {
+ if (!tables->is_derived())
+ tables->set_derived();
+ goto end;
+ }
+ /*
+ We restore view's name and database wiped out by derived tables
+ processing and fall back to standard open process in order to
+ obtain proper metadata locks and do other necessary steps like
+ stored routine processing.
+ */
+ tables->db= tables->view_db;
+ tables->table_name= tables->view_name;
+ }
+
+ if (!tables->derived && is_infoschema_db(&tables->db))
+ {
+ /*
+ Check whether the information schema contains a table
+ whose name is tables->schema_table_name
+ */
+ ST_SCHEMA_TABLE *schema_table= tables->schema_table;
+ if (!schema_table ||
+ (schema_table->hidden &&
+ ((sql_command_flags[lex->sql_command] & CF_STATUS_COMMAND) == 0 ||
+ /*
+ this check is used for show columns|keys from I_S hidden table
+ */
+ lex->sql_command == SQLCOM_SHOW_FIELDS ||
+ lex->sql_command == SQLCOM_SHOW_KEYS)))
+ {
+ my_error(ER_UNKNOWN_TABLE, MYF(0),
+ tables->table_name.str, INFORMATION_SCHEMA_NAME.str);
+ DBUG_RETURN(1);
+ }
+ }
+ /*
+ If this TABLE_LIST object is a placeholder for an information_schema
+ table, create a temporary table to represent the information_schema
+ table in the query. Do not fill it yet - will be filled during
+ execution.
+ */
+ if (tables->schema_table)
+ {
+ /*
+ If this information_schema table is merged into a mergeable
+ view, ignore it for now -- it will be filled when its respective
+ TABLE_LIST is processed. This code works only during re-execution.
+ */
+ if (tables->view)
+ {
+ MDL_ticket *mdl_ticket;
+ /*
+ We still need to take a MDL lock on the merged view to protect
+ it from concurrent changes.
+ */
+ if (!open_table_get_mdl_lock(thd, ot_ctx, &tables->mdl_request,
+ flags, &mdl_ticket) &&
+ mdl_ticket != NULL)
+ goto process_view_routines;
+ /* Fall-through to return error. */
+ }
+ else if (!mysql_schema_table(thd, lex, tables) &&
+ !check_and_update_table_version(thd, tables, tables->table->s))
+ {
+ goto end;
+ }
+ error= TRUE;
+ goto end;
+ }
+ DBUG_PRINT("tcache", ("opening table: '%s'.'%s' item: %p",
+ tables->db.str, tables->table_name.str, tables));
+ (*counter)++;
+
+ /*
+ Not a placeholder: must be a base/temporary table or a view. Let us open it.
+ */
+ if (tables->table)
+ {
+ /*
+ If this TABLE_LIST object has an associated open TABLE object
+ (TABLE_LIST::table is not NULL), that TABLE object must be a pre-opened
+ temporary table or SEQUENCE (see sequence_insert()).
+ */
+ DBUG_ASSERT(is_temporary_table(tables) || tables->table->s->sequence);
+ if (tables->sequence &&
+ tables->table->s->table_type != TABLE_TYPE_SEQUENCE)
+ {
+ my_error(ER_NOT_SEQUENCE, MYF(0), tables->db.str, tables->alias.str);
+ DBUG_RETURN(true);
+ }
+ }
+ else if (tables->open_type == OT_TEMPORARY_ONLY)
+ {
+ /*
+ OT_TEMPORARY_ONLY means that we are in CREATE TEMPORARY TABLE statement.
+ Also such table list element can't correspond to prelocking placeholder
+ or to underlying table of merge table.
+ So existing temporary table should have been preopened by this moment
+ and we can simply continue without trying to open temporary or base
+ table.
+ */
+ DBUG_ASSERT(tables->open_strategy);
+ DBUG_ASSERT(!tables->prelocking_placeholder);
+ DBUG_ASSERT(!tables->parent_l);
+ DBUG_RETURN(0);
+ }
+
+ /* Not a placeholder: must be a base table or a view. Let us open it. */
+ if (tables->prelocking_placeholder)
+ {
+ /*
+ For the tables added by the pre-locking code, attempt to open
+ the table but fail silently if the table does not exist.
+ The real failure will occur when/if a statement attempts to use
+ that table.
+ */
+ No_such_table_error_handler no_such_table_handler;
+ thd->push_internal_handler(&no_such_table_handler);
+
+ /*
+ We're opening a table from the prelocking list.
+
+ Since this table list element might have been added after pre-opening
+ of temporary tables we have to try to open temporary table for it.
+
+ We can't simply skip this table list element and postpone opening of
+ temporary table till the execution of substatement for several reasons:
+ - Temporary table can be a MERGE table with base underlying tables,
+ so its underlying tables has to be properly open and locked at
+ prelocking stage.
+ - Temporary table can be a MERGE table and we might be in PREPARE
+ phase for a prepared statement. In this case it is important to call
+ HA_ATTACH_CHILDREN for all merge children.
+ This is necessary because merge children remember "TABLE_SHARE ref type"
+ and "TABLE_SHARE def version" in the HA_ATTACH_CHILDREN operation.
+ If HA_ATTACH_CHILDREN is not called, these attributes are not set.
+ Then, during the first EXECUTE, those attributes need to be updated.
+ That would cause statement re-preparing (because changing those
+ attributes during EXECUTE is caught by THD::m_reprepare_observers).
+ The problem is that since those attributes are not set in merge
+ children, another round of PREPARE will not help.
+ */
+ if (!thd->has_temporary_tables() ||
+ (!(error= thd->open_temporary_table(tables)) &&
+ !tables->table))
+ error= open_table(thd, tables, ot_ctx);
+
+ thd->pop_internal_handler();
+ safe_to_ignore_table= no_such_table_handler.safely_trapped_errors();
+ }
+ else if (tables->parent_l && (thd->open_options & HA_OPEN_FOR_REPAIR))
+ {
+ /*
+ Also fail silently for underlying tables of a MERGE table if this
+ table is opened for CHECK/REPAIR TABLE statement. This is needed
+ to provide complete list of problematic underlying tables in
+ CHECK/REPAIR TABLE output.
+ */
+ Repair_mrg_table_error_handler repair_mrg_table_handler;
+ thd->push_internal_handler(&repair_mrg_table_handler);
+
+ if (!thd->has_temporary_tables() ||
+ (!(error= thd->open_temporary_table(tables)) &&
+ !tables->table))
+ error= open_table(thd, tables, ot_ctx);
+
+ thd->pop_internal_handler();
+ safe_to_ignore_table= repair_mrg_table_handler.safely_trapped_errors();
+ }
+ else
+ {
+ if (tables->parent_l)
+ {
+ /*
+ Even if we are opening table not from the prelocking list we
+ still might need to look for a temporary table if this table
+ list element corresponds to underlying table of a merge table.
+ */
+ if (thd->has_temporary_tables())
+ error= thd->open_temporary_table(tables);
+ }
+
+ if (!error && !tables->table)
+ error= open_table(thd, tables, ot_ctx);
+ }
+
+ if (unlikely(error))
+ {
+ if (! ot_ctx->can_recover_from_failed_open() && safe_to_ignore_table)
+ {
+ DBUG_PRINT("info", ("open_table: ignoring table '%s'.'%s'",
+ tables->db.str, tables->alias.str));
+ error= FALSE;
+ }
+ goto end;
+ }
+
+ /*
+ We can't rely on simple check for TABLE_LIST::view to determine
+ that this is a view since during re-execution we might reopen
+ ordinary table in place of view and thus have TABLE_LIST::view
+ set from repvious execution and TABLE_LIST::table set from
+ current.
+ */
+ if (!tables->table && tables->view)
+ {
+ /* VIEW placeholder */
+ (*counter)--;
+
+ /*
+ tables->next_global list consists of two parts:
+ 1) Query tables and underlying tables of views.
+ 2) Tables used by all stored routines that this statement invokes on
+ execution.
+ We need to know where the bound between these two parts is. If we've
+ just opened a view, which was the last table in part #1, and it
+ has added its base tables after itself, adjust the boundary pointer
+ accordingly.
+ */
+ if (lex->query_tables_own_last == &(tables->next_global) &&
+ tables->view->query_tables)
+ lex->query_tables_own_last= tables->view->query_tables_last;
+ /*
+ Let us free memory used by 'sroutines' hash here since we never
+ call destructor for this LEX.
+ */
+ my_hash_free(&tables->view->sroutines);
+ goto process_view_routines;
+ }
+
+ /*
+ Special types of open can succeed but still don't set
+ TABLE_LIST::table to anything.
+ */
+ if (tables->open_strategy && !tables->table)
+ goto end;
+
+ error= extend_table_list(thd, tables, prelocking_strategy, has_prelocking_list);
+ if (unlikely(error))
+ goto end;
+
+ /* Copy grant information from TABLE_LIST instance to TABLE one. */
+ tables->table->grant= tables->grant;
+
+ /* Check and update metadata version of a base table. */
+ error= check_and_update_table_version(thd, tables, tables->table->s);
+
+ if (unlikely(error))
+ goto end;
+ /*
+ After opening a MERGE table add the children to the query list of
+ tables, so that they are opened too.
+ Note that placeholders don't have the handler open.
+ */
+ /* MERGE tables need to access parent and child TABLE_LISTs. */
+ DBUG_ASSERT(tables->table->pos_in_table_list == tables);
+ /* Non-MERGE tables ignore this call. */
+ if (tables->table->file->extra(HA_EXTRA_ADD_CHILDREN_LIST))
+ {
+ error= TRUE;
+ goto end;
+ }
+
+process_view_routines:
+ /*
+ Again we may need cache all routines used by this view and add
+ tables used by them to table list.
+ */
+ if (tables->view &&
+ thd->locked_tables_mode <= LTM_LOCK_TABLES &&
+ ! has_prelocking_list)
+ {
+ bool need_prelocking= FALSE;
+ TABLE_LIST **save_query_tables_last= lex->query_tables_last;
+
+ error= prelocking_strategy->handle_view(thd, lex, tables,
+ &need_prelocking);
+
+ if (need_prelocking && ! lex->requires_prelocking())
+ lex->mark_as_requiring_prelocking(save_query_tables_last);
+
+ if (unlikely(error))
+ goto end;
+ }
+
+end:
+ DBUG_RETURN(error);
+}
+
+
+static bool upgrade_lock_if_not_exists(THD *thd,
+ const DDL_options_st &create_info,
+ TABLE_LIST *create_table,
+ ulong lock_wait_timeout)
+{
+ DBUG_ENTER("upgrade_lock_if_not_exists");
+
+ if (thd->lex->sql_command == SQLCOM_CREATE_TABLE ||
+ thd->lex->sql_command == SQLCOM_CREATE_SEQUENCE)
+ {
+ DEBUG_SYNC(thd,"create_table_before_check_if_exists");
+ if (!create_info.or_replace() &&
+ ha_table_exists(thd, &create_table->db, &create_table->table_name,
+ &create_table->db_type))
+ {
+ if (create_info.if_not_exists())
+ {
+ push_warning_printf(thd, Sql_condition::WARN_LEVEL_NOTE,
+ ER_TABLE_EXISTS_ERROR,
+ ER_THD(thd, ER_TABLE_EXISTS_ERROR),
+ create_table->table_name.str);
+ }
+ else
+ my_error(ER_TABLE_EXISTS_ERROR, MYF(0), create_table->table_name.str);
+ DBUG_RETURN(true);
+ }
+ DBUG_RETURN(thd->mdl_context.upgrade_shared_lock(
+ create_table->mdl_request.ticket,
+ MDL_EXCLUSIVE,
+ lock_wait_timeout));
+ }
+ DBUG_RETURN(false);
+}
+
+
+/**
+ Acquire upgradable (SNW, SNRW) metadata locks on tables used by
+ LOCK TABLES or by a DDL statement. Under LOCK TABLES, we can't take
+ new locks, so use open_tables_check_upgradable_mdl() instead.
+
+ @param thd Thread context.
+ @param options DDL options.
+ @param tables_start Start of list of tables on which upgradable locks
+ should be acquired.
+ @param tables_end End of list of tables.
+ @param lock_wait_timeout Seconds to wait before timeout.
+ @param flags Bitmap of flags to modify how the tables will be
+ open, see open_table() description for details.
+
+ @retval FALSE Success.
+ @retval TRUE Failure (e.g. connection was killed) or table existed
+ for a CREATE TABLE.
+
+ @notes
+ In case of CREATE TABLE we avoid a wait for tables that are in use
+ by first trying to do a meta data lock with timeout == 0. If we get a
+ timeout we will check if table exists (it should) and retry with
+ normal timeout if it didn't exists.
+ Note that for CREATE TABLE IF EXISTS we only generate a warning
+ but still return TRUE (to abort the calling open_table() function).
+ On must check THD->is_error() if one wants to distinguish between warning
+ and error. If table existed, tables_start->db_type is set to the handlerton
+ for the found table.
+*/
+
+bool
+lock_table_names(THD *thd, const DDL_options_st &options,
+ TABLE_LIST *tables_start, TABLE_LIST *tables_end,
+ ulong lock_wait_timeout, uint flags)
+{
+ MDL_request_list mdl_requests;
+ TABLE_LIST *table;
+ MDL_request global_request;
+ MDL_savepoint mdl_savepoint;
+ DBUG_ENTER("lock_table_names");
+
+ DBUG_ASSERT(!thd->locked_tables_mode);
+
+ for (table= tables_start; table && table != tables_end;
+ table= table->next_global)
+ {
+ DBUG_PRINT("info", ("mdl_request.type: %d open_type: %d",
+ table->mdl_request.type, table->open_type));
+ if (table->mdl_request.type < MDL_SHARED_UPGRADABLE ||
+ table->mdl_request.type == MDL_SHARED_READ_ONLY ||
+ table->open_type == OT_TEMPORARY_ONLY ||
+ (table->open_type == OT_TEMPORARY_OR_BASE && is_temporary_table(table)))
+ {
+ continue;
+ }
+
+ /* Write lock on normal tables is not allowed in a read only transaction. */
+ if (thd->tx_read_only)
+ {
+ my_error(ER_CANT_EXECUTE_IN_READ_ONLY_TRANSACTION, MYF(0));
+ DBUG_RETURN(true);
+ }
+
+ /* Scoped locks: Take intention exclusive locks on all involved schemas. */
+ if (!(flags & MYSQL_OPEN_SKIP_SCOPED_MDL_LOCK))
+ {
+ MDL_request *schema_request= new (thd->mem_root) MDL_request;
+ if (schema_request == NULL)
+ DBUG_RETURN(TRUE);
+ MDL_REQUEST_INIT(schema_request, MDL_key::SCHEMA, table->db.str, "",
+ MDL_INTENTION_EXCLUSIVE, MDL_TRANSACTION);
+ mdl_requests.push_front(schema_request);
+ }
+
+ mdl_requests.push_front(&table->mdl_request);
+ }
+
+ if (mdl_requests.is_empty())
+ DBUG_RETURN(FALSE);
+
+ if (flags & MYSQL_OPEN_SKIP_SCOPED_MDL_LOCK)
+ {
+ DBUG_RETURN(thd->mdl_context.acquire_locks(&mdl_requests,
+ lock_wait_timeout) ||
+ upgrade_lock_if_not_exists(thd, options, tables_start,
+ lock_wait_timeout));
+ }
+
+ /* Protect this statement against concurrent BACKUP STAGE or FTWRL. */
+ if (thd->has_read_only_protection())
+ DBUG_RETURN(true);
+
+ MDL_REQUEST_INIT(&global_request, MDL_key::BACKUP, "", "", MDL_BACKUP_DDL,
+ MDL_STATEMENT);
+ mdl_savepoint= thd->mdl_context.mdl_savepoint();
+
+ while (!thd->mdl_context.acquire_locks(&mdl_requests, lock_wait_timeout) &&
+ !upgrade_lock_if_not_exists(thd, options, tables_start,
+ lock_wait_timeout) &&
+ !thd->mdl_context.try_acquire_lock(&global_request))
+ {
+ if (global_request.ticket)
+ {
+ thd->mdl_backup_ticket= global_request.ticket;
+ DBUG_RETURN(false);
+ }
+
+ /*
+ There is ongoing or pending BACKUP STAGE or FTWRL.
+ Wait until it finishes and re-try.
+ */
+ thd->mdl_context.rollback_to_savepoint(mdl_savepoint);
+ if (thd->mdl_context.acquire_lock(&global_request, lock_wait_timeout))
+ break;
+ thd->mdl_context.rollback_to_savepoint(mdl_savepoint);
+
+ /* Reset tickets for all acquired locks */
+ global_request.ticket= 0;
+ MDL_request_list::Iterator it(mdl_requests);
+ while (auto mdl_request= it++)
+ mdl_request->ticket= 0;
+ }
+ DBUG_RETURN(true);
+}
+
+
+/**
+ Check for upgradable (SNW, SNRW) metadata locks on tables to be opened
+ for a DDL statement. Under LOCK TABLES, we can't take new locks, so we
+ must check if appropriate locks were pre-acquired.
+
+ @param thd Thread context.
+ @param tables_start Start of list of tables on which upgradable locks
+ should be searched for.
+ @param tables_end End of list of tables.
+ @param flags Bitmap of flags to modify how the tables will be
+ open, see open_table() description for details.
+
+ @retval FALSE Success.
+ @retval TRUE Failure (e.g. connection was killed)
+*/
+
+static bool
+open_tables_check_upgradable_mdl(THD *thd, TABLE_LIST *tables_start,
+ TABLE_LIST *tables_end, uint flags)
+{
+ TABLE_LIST *table;
+
+ DBUG_ASSERT(thd->locked_tables_mode);
+
+ for (table= tables_start; table && table != tables_end;
+ table= table->next_global)
+ {
+ /*
+ Check below needs to be updated if this function starts
+ called for SRO locks.
+ */
+ DBUG_ASSERT(table->mdl_request.type != MDL_SHARED_READ_ONLY);
+ if (table->mdl_request.type < MDL_SHARED_UPGRADABLE ||
+ table->open_type == OT_TEMPORARY_ONLY ||
+ (table->open_type == OT_TEMPORARY_OR_BASE && is_temporary_table(table)))
+ {
+ continue;
+ }
+
+ /*
+ We don't need to do anything about the found TABLE instance as it
+ will be handled later in open_tables(), we only need to check that
+ an upgradable lock is already acquired. When we enter LOCK TABLES
+ mode, SNRW locks are acquired before all other locks. So if under
+ LOCK TABLES we find that there is TABLE instance with upgradeable
+ lock, all other instances of TABLE for the same table will have the
+ same ticket.
+
+ Note that this works OK even for CREATE TABLE statements which
+ request X type of metadata lock. This is because under LOCK TABLES
+ such statements don't create the table but only check if it exists
+ or, in most complex case, only insert into it.
+ Thus SNRW lock should be enough.
+
+ Note that find_table_for_mdl_upgrade() will report an error if
+ no suitable ticket is found.
+ */
+ if (!find_table_for_mdl_upgrade(thd, table->db.str, table->table_name.str,
+ NULL))
+ return TRUE;
+ }
+
+ return FALSE;
+}
+
+
+/**
+ Open all tables in list
+
+ @param[in] thd Thread context.
+ @param[in] options DDL options.
+ @param[in,out] start List of tables to be open (it can be adjusted for
+ statement that uses tables only implicitly, e.g.
+ for "SELECT f1()").
+ @param[out] counter Number of tables which were open.
+ @param[in] flags Bitmap of flags to modify how the tables will be
+ open, see open_table() description for details.
+ @param[in] prelocking_strategy Strategy which specifies how prelocking
+ algorithm should work for this statement.
+
+ @note
+ Unless we are already in prelocked mode and prelocking strategy prescribes
+ so this function will also precache all SP/SFs explicitly or implicitly
+ (via views and triggers) used by the query and add tables needed for their
+ execution to table list. Statement that uses SFs, invokes triggers or
+ requires foreign key checks will be marked as requiring prelocking.
+ Prelocked mode will be enabled for such query during lock_tables() call.
+
+ If query for which we are opening tables is already marked as requiring
+ prelocking it won't do such precaching and will simply reuse table list
+ which is already built.
+
+ @retval FALSE Success.
+ @retval TRUE Error, reported.
+*/
+
+bool open_tables(THD *thd, const DDL_options_st &options,
+ TABLE_LIST **start, uint *counter, uint flags,
+ Prelocking_strategy *prelocking_strategy)
+{
+ /*
+ We use pointers to "next_global" member in the last processed
+ TABLE_LIST element and to the "next" member in the last processed
+ Sroutine_hash_entry element as iterators over, correspondingly,
+ the table list and stored routines list which stay valid and allow
+ to continue iteration when new elements are added to the tail of
+ the lists.
+ */
+ TABLE_LIST **table_to_open;
+ Sroutine_hash_entry **sroutine_to_open;
+ TABLE_LIST *tables;
+ Open_table_context ot_ctx(thd, flags);
+ bool error= FALSE;
+ bool some_routine_modifies_data= FALSE;
+ bool has_prelocking_list;
+ DBUG_ENTER("open_tables");
+
+ /* Data access in XA transaction is only allowed when it is active. */
+ for (TABLE_LIST *table= *start; table; table= table->next_global)
+ if (!table->schema_table)
+ {
+ if (thd->transaction->xid_state.check_has_uncommitted_xa())
+ {
+ thd->transaction->xid_state.er_xaer_rmfail();
+ DBUG_RETURN(true);
+ }
+ else
+ break;
+ }
+
+ thd->current_tablenr= 0;
+restart:
+ /*
+ Close HANDLER tables which are marked for flush or against which there
+ are pending exclusive metadata locks. This is needed both in order to
+ avoid deadlocks and to have a point during statement execution at
+ which such HANDLERs are closed even if they don't create problems for
+ the current session (i.e. to avoid having a DDL blocked by HANDLERs
+ opened for a long time).
+ */
+ if (thd->handler_tables_hash.records)
+ mysql_ha_flush(thd);
+
+ has_prelocking_list= thd->lex->requires_prelocking();
+ table_to_open= start;
+ sroutine_to_open= &thd->lex->sroutines_list.first;
+ *counter= 0;
+ THD_STAGE_INFO(thd, stage_opening_tables);
+ prelocking_strategy->reset(thd);
+
+ /*
+ If we are executing LOCK TABLES statement or a DDL statement
+ (in non-LOCK TABLES mode) we might have to acquire upgradable
+ semi-exclusive metadata locks (SNW or SNRW) on some of the
+ tables to be opened.
+ When executing CREATE TABLE .. If NOT EXISTS .. SELECT, the
+ table may not yet exist, in which case we acquire an exclusive
+ lock.
+ We acquire all such locks at once here as doing this in one
+ by one fashion may lead to deadlocks or starvation. Later when
+ we will be opening corresponding table pre-acquired metadata
+ lock will be reused (thanks to the fact that in recursive case
+ metadata locks are acquired without waiting).
+ */
+ if (! (flags & (MYSQL_OPEN_HAS_MDL_LOCK |
+ MYSQL_OPEN_FORCE_SHARED_MDL |
+ MYSQL_OPEN_FORCE_SHARED_HIGH_PRIO_MDL)))
+ {
+ if (thd->locked_tables_mode)
+ {
+ /*
+ Under LOCK TABLES, we can't acquire new locks, so we instead
+ need to check if appropriate locks were pre-acquired.
+ */
+ if (open_tables_check_upgradable_mdl(thd, *start,
+ thd->lex->first_not_own_table(),
+ flags))
+ {
+ error= TRUE;
+ goto error;
+ }
+ }
+ else
+ {
+ TABLE_LIST *table;
+ if (lock_table_names(thd, options, *start,
+ thd->lex->first_not_own_table(),
+ ot_ctx.get_timeout(), flags))
+ {
+ error= TRUE;
+ goto error;
+ }
+ for (table= *start; table && table != thd->lex->first_not_own_table();
+ table= table->next_global)
+ {
+ if (table->mdl_request.type >= MDL_SHARED_UPGRADABLE)
+ table->mdl_request.ticket= NULL;
+ }
+ }
+ }
+
+ /*
+ Perform steps of prelocking algorithm until there are unprocessed
+ elements in prelocking list/set.
+ */
+ while (*table_to_open ||
+ (thd->locked_tables_mode <= LTM_LOCK_TABLES && *sroutine_to_open))
+ {
+ /*
+ For every table in the list of tables to open, try to find or open
+ a table.
+ */
+ for (tables= *table_to_open; tables;
+ table_to_open= &tables->next_global, tables= tables->next_global)
+ {
+ error= open_and_process_table(thd, tables, counter, flags,
+ prelocking_strategy, has_prelocking_list,
+ &ot_ctx);
+
+ if (unlikely(error))
+ {
+ if (ot_ctx.can_recover_from_failed_open())
+ {
+ /*
+ We have met exclusive metadata lock or old version of table.
+ Now we have to close all tables and release metadata locks.
+ We also have to throw away set of prelocked tables (and thus
+ close tables from this set that were open by now) since it
+ is possible that one of tables which determined its content
+ was changed.
+
+ Instead of implementing complex/non-robust logic mentioned
+ above we simply close and then reopen all tables.
+
+ We have to save pointer to table list element for table which we
+ have failed to open since closing tables can trigger removal of
+ elements from the table list (if MERGE tables are involved),
+ */
+ close_tables_for_reopen(thd, start, ot_ctx.start_of_statement_svp());
+
+ /*
+ Here we rely on the fact that 'tables' still points to the valid
+ TABLE_LIST element. Altough currently this assumption is valid
+ it may change in future.
+ */
+ if (ot_ctx.recover_from_failed_open())
+ goto error;
+
+ /* Re-open temporary tables after close_tables_for_reopen(). */
+ if (thd->open_temporary_tables(*start))
+ goto error;
+
+ error= FALSE;
+ goto restart;
+ }
+ goto error;
+ }
+
+ DEBUG_SYNC(thd, "open_tables_after_open_and_process_table");
+ }
+
+ /*
+ If we are not already in prelocked mode and extended table list is
+ not yet built for our statement we need to cache routines it uses
+ and build the prelocking list for it.
+ If we are not in prelocked mode but have built the extended table
+ list, we still need to call open_and_process_routine() to take
+ MDL locks on the routines.
+ */
+ if (thd->locked_tables_mode <= LTM_LOCK_TABLES && *sroutine_to_open)
+ {
+ /*
+ Process elements of the prelocking set which are present there
+ since parsing stage or were added to it by invocations of
+ Prelocking_strategy methods in the above loop over tables.
+
+ For example, if element is a routine, cache it and then,
+ if prelocking strategy prescribes so, add tables it uses to the
+ table list and routines it might invoke to the prelocking set.
+ */
+ for (Sroutine_hash_entry *rt= *sroutine_to_open; rt;
+ sroutine_to_open= &rt->next, rt= rt->next)
+ {
+ bool need_prelocking= false;
+ bool routine_modifies_data;
+ TABLE_LIST **save_query_tables_last= thd->lex->query_tables_last;
+
+ error= open_and_process_routine(thd, thd->lex, rt, prelocking_strategy,
+ has_prelocking_list, &ot_ctx,
+ &need_prelocking,
+ &routine_modifies_data);
+
+ // Remember if any of SF modifies data.
+ some_routine_modifies_data|= routine_modifies_data;
+
+ if (need_prelocking && ! thd->lex->requires_prelocking())
+ thd->lex->mark_as_requiring_prelocking(save_query_tables_last);
+
+ if (need_prelocking && ! *start)
+ *start= thd->lex->query_tables;
+
+ if (unlikely(error))
+ {
+ if (ot_ctx.can_recover_from_failed_open())
+ {
+ close_tables_for_reopen(thd, start,
+ ot_ctx.start_of_statement_svp());
+ if (ot_ctx.recover_from_failed_open())
+ goto error;
+
+ /* Re-open temporary tables after close_tables_for_reopen(). */
+ if (thd->open_temporary_tables(*start))
+ goto error;
+
+ error= FALSE;
+ goto restart;
+ }
+ /*
+ Serious error during reading stored routines from mysql.proc table.
+ Something is wrong with the table or its contents, and an error has
+ been emitted; we must abort.
+ */
+ goto error;
+ }
+ }
+ }
+ if ((error= prelocking_strategy->handle_end(thd)))
+ goto error;
+ }
+
+ /*
+ After successful open of all tables, including MERGE parents and
+ children, attach the children to their parents. At end of statement,
+ the children are detached. Attaching and detaching are always done,
+ even under LOCK TABLES.
+
+ We also convert all TL_WRITE_DEFAULT and TL_READ_DEFAULT locks to
+ appropriate "real" lock types to be used for locking and to be passed
+ to storage engine.
+
+ And start wsrep TOI if needed.
+ */
+ for (tables= *start; tables; tables= tables->next_global)
+ {
+ TABLE *tbl= tables->table;
+
+ if (!tbl)
+ continue;
+
+ /* Schema tables may not have a TABLE object here. */
+ if (tbl->file->ha_table_flags() & HA_CAN_MULTISTEP_MERGE)
+ {
+ /* MERGE tables need to access parent and child TABLE_LISTs. */
+ DBUG_ASSERT(tbl->pos_in_table_list == tables);
+ if (tbl->file->extra(HA_EXTRA_ATTACH_CHILDREN))
+ {
+ error= TRUE;
+ goto error;
+ }
+ }
+
+ /* Set appropriate TABLE::lock_type. */
+ if (tbl && tables->lock_type != TL_UNLOCK && !thd->locked_tables_mode)
+ {
+ if (tables->lock_type == TL_WRITE_DEFAULT)
+ tbl->reginfo.lock_type= thd->update_lock_default;
+ else if (tables->lock_type == TL_READ_DEFAULT)
+ tbl->reginfo.lock_type=
+ read_lock_type_for_table(thd, thd->lex, tables,
+ some_routine_modifies_data);
+ else
+ tbl->reginfo.lock_type= tables->lock_type;
+ }
+ }
+
+#ifdef WITH_WSREP
+ if (WSREP(thd) &&
+ wsrep_replicate_myisam &&
+ (*start) &&
+ (*start)->table &&
+ (*start)->table->file->ht == myisam_hton &&
+ wsrep_thd_is_local(thd) &&
+ !is_stat_table(&(*start)->db, &(*start)->alias) &&
+ thd->get_command() != COM_STMT_PREPARE &&
+ ((thd->lex->sql_command == SQLCOM_INSERT ||
+ thd->lex->sql_command == SQLCOM_INSERT_SELECT ||
+ thd->lex->sql_command == SQLCOM_REPLACE ||
+ thd->lex->sql_command == SQLCOM_REPLACE_SELECT ||
+ thd->lex->sql_command == SQLCOM_UPDATE ||
+ thd->lex->sql_command == SQLCOM_UPDATE_MULTI ||
+ thd->lex->sql_command == SQLCOM_LOAD ||
+ thd->lex->sql_command == SQLCOM_DELETE)))
+ {
+ wsrep_before_rollback(thd, true);
+ wsrep_after_rollback(thd, true);
+ wsrep_after_statement(thd);
+ WSREP_TO_ISOLATION_BEGIN(NULL, NULL, (*start));
+ }
+#endif /* WITH_WSREP */
+
+error:
+#ifdef WITH_WSREP
+wsrep_error_label:
+#endif
+ THD_STAGE_INFO(thd, stage_after_opening_tables);
+ thd_proc_info(thd, 0);
+
+ if (unlikely(error) && *table_to_open)
+ {
+ (*table_to_open)->table= NULL;
+ }
+ DBUG_PRINT("open_tables", ("returning: %d", (int) error));
+ DBUG_RETURN(error);
+}
+
+
+/**
+ Defines how prelocking algorithm for DML statements should handle routines:
+ - For CALL statements we do unrolling (i.e. open and lock tables for each
+ sub-statement individually). So for such statements prelocking is enabled
+ only if stored functions are used in parameter list and only for period
+ during which we calculate values of parameters. Thus in this strategy we
+ ignore procedure which is directly called by such statement and extend
+ the prelocking set only with tables/functions used by SF called from the
+ parameter list.
+ - For any other statement any routine which is directly or indirectly called
+ by statement is going to be executed in prelocked mode. So in this case we
+ simply add all tables and routines used by it to the prelocking set.
+
+ @param[in] thd Thread context.
+ @param[in] prelocking_ctx Prelocking context of the statement.
+ @param[in] rt Prelocking set element describing routine.
+ @param[in] sp Routine body.
+ @param[out] need_prelocking Set to TRUE if method detects that prelocking
+ required, not changed otherwise.
+
+ @retval FALSE Success.
+ @retval TRUE Failure (OOM).
+*/
+
+bool DML_prelocking_strategy::
+handle_routine(THD *thd, Query_tables_list *prelocking_ctx,
+ Sroutine_hash_entry *rt, sp_head *sp, bool *need_prelocking)
+{
+ /*
+ We assume that for any "CALL proc(...)" statement sroutines_list will
+ have 'proc' as first element (it may have several, consider e.g.
+ "proc(sp_func(...)))". This property is currently guaranted by the
+ parser.
+ */
+
+ if (rt != (Sroutine_hash_entry*)prelocking_ctx->sroutines_list.first ||
+ rt->mdl_request.key.mdl_namespace() != MDL_key::PROCEDURE)
+ {
+ *need_prelocking= TRUE;
+ sp_update_stmt_used_routines(thd, prelocking_ctx, &sp->m_sroutines,
+ rt->belong_to_view);
+ (void)sp->add_used_tables_to_table_list(thd,
+ &prelocking_ctx->query_tables_last,
+ rt->belong_to_view);
+ }
+ sp->propagate_attributes(prelocking_ctx);
+ return FALSE;
+}
+
+
+/*
+ @note this can be changed to use a hash, instead of scanning the linked
+ list, if the performance of this function will ever become an issue
+*/
+bool table_already_fk_prelocked(TABLE_LIST *tl, LEX_CSTRING *db,
+ LEX_CSTRING *table, thr_lock_type lock_type)
+{
+ for (; tl; tl= tl->next_global )
+ {
+ if (tl->lock_type >= lock_type &&
+ tl->prelocking_placeholder == TABLE_LIST::PRELOCK_FK &&
+ strcmp(tl->db.str, db->str) == 0 &&
+ strcmp(tl->table_name.str, table->str) == 0)
+ return true;
+ }
+ return false;
+}
+
+
+static bool internal_table_exists(TABLE_LIST *global_list,
+ const char *table_name)
+{
+ do
+ {
+ if (global_list->table_name.str == table_name)
+ return 1;
+ } while ((global_list= global_list->next_global));
+ return 0;
+}
+
+
+static bool
+add_internal_tables(THD *thd, Query_tables_list *prelocking_ctx,
+ TABLE_LIST *tables)
+{
+ TABLE_LIST *global_table_list= prelocking_ctx->query_tables;
+ DBUG_ENTER("add_internal_tables");
+
+ do
+ {
+ DBUG_PRINT("info", ("table name: %s", tables->table_name.str));
+ /*
+ Skip table if already in the list. Can happen with prepared statements
+ */
+ if (tables->next_local &&
+ internal_table_exists(global_table_list, tables->table_name.str))
+ continue;
+
+ TABLE_LIST *tl= (TABLE_LIST *) thd->alloc(sizeof(TABLE_LIST));
+ if (!tl)
+ DBUG_RETURN(TRUE);
+ tl->init_one_table_for_prelocking(&tables->db,
+ &tables->table_name,
+ NULL, tables->lock_type,
+ TABLE_LIST::PRELOCK_NONE,
+ 0, 0,
+ &prelocking_ctx->query_tables_last,
+ tables->for_insert_data);
+ /*
+ Store link to the new table_list that will be used by open so that
+ Item_func_nextval() can find it
+ */
+ tables->next_local= tl;
+ DBUG_PRINT("info", ("table name: %s added", tables->table_name.str));
+ } while ((tables= tables->next_global));
+ DBUG_RETURN(FALSE);
+}
+
+/**
+ Extend the table_list to include foreign tables for prelocking.
+
+ @param[in] thd Thread context.
+ @param[in] prelocking_ctx Prelocking context of the statement.
+ @param[in] table_list Table list element for table.
+ @param[in] sp Routine body.
+ @param[out] need_prelocking Set to TRUE if method detects that prelocking
+ required, not changed otherwise.
+
+ @retval FALSE Success.
+ @retval TRUE Failure (OOM).
+*/
+inline bool
+prepare_fk_prelocking_list(THD *thd, Query_tables_list *prelocking_ctx,
+ TABLE_LIST *table_list, bool *need_prelocking,
+ uint8 op)
+{
+ DBUG_ENTER("prepare_fk_prelocking_list");
+ List <FOREIGN_KEY_INFO> fk_list;
+ List_iterator<FOREIGN_KEY_INFO> fk_list_it(fk_list);
+ FOREIGN_KEY_INFO *fk;
+ Query_arena *arena, backup;
+ TABLE *table= table_list->table;
+
+ arena= thd->activate_stmt_arena_if_needed(&backup);
+
+ table->file->get_parent_foreign_key_list(thd, &fk_list);
+ if (unlikely(thd->is_error()))
+ {
+ if (arena)
+ thd->restore_active_arena(arena, &backup);
+ return TRUE;
+ }
+
+ *need_prelocking= TRUE;
+
+ while ((fk= fk_list_it++))
+ {
+ // FK_OPTION_RESTRICT and FK_OPTION_NO_ACTION only need read access
+ thr_lock_type lock_type;
+
+ if ((op & (1 << TRG_EVENT_DELETE) && fk_modifies_child(fk->delete_method))
+ || (op & (1 << TRG_EVENT_UPDATE) && fk_modifies_child(fk->update_method)))
+ lock_type= TL_WRITE_ALLOW_WRITE;
+ else
+ lock_type= TL_READ;
+
+ if (table_already_fk_prelocked(prelocking_ctx->query_tables,
+ fk->foreign_db, fk->foreign_table,
+ lock_type))
+ continue;
+
+ TABLE_LIST *tl= (TABLE_LIST *) thd->alloc(sizeof(TABLE_LIST));
+ tl->init_one_table_for_prelocking(fk->foreign_db,
+ fk->foreign_table,
+ NULL, lock_type,
+ TABLE_LIST::PRELOCK_FK,
+ table_list->belong_to_view, op,
+ &prelocking_ctx->query_tables_last,
+ table_list->for_insert_data);
+ }
+ if (arena)
+ thd->restore_active_arena(arena, &backup);
+ DBUG_RETURN(FALSE);
+}
+
+/**
+ Defines how prelocking algorithm for DML statements should handle table list
+ elements:
+ - If table has triggers we should add all tables and routines
+ used by them to the prelocking set.
+
+ We do not need to acquire metadata locks on trigger names
+ in DML statements, since all DDL statements
+ that change trigger metadata always lock their
+ subject tables.
+
+ @param[in] thd Thread context.
+ @param[in] prelocking_ctx Prelocking context of the statement.
+ @param[in] table_list Table list element for table.
+ @param[in] sp Routine body.
+ @param[out] need_prelocking Set to TRUE if method detects that prelocking
+ required, not changed otherwise.
+
+ @retval FALSE Success.
+ @retval TRUE Failure (OOM).
+*/
+
+bool DML_prelocking_strategy::
+handle_table(THD *thd, Query_tables_list *prelocking_ctx,
+ TABLE_LIST *table_list, bool *need_prelocking)
+{
+ DBUG_ENTER("handle_table");
+ TABLE *table= table_list->table;
+ /* We rely on a caller to check that table is going to be changed. */
+ DBUG_ASSERT(table_list->lock_type >= TL_WRITE_ALLOW_WRITE ||
+ thd->lex->default_used);
+
+ if (table_list->trg_event_map)
+ {
+ if (table->triggers)
+ {
+ *need_prelocking= TRUE;
+
+ if (table->triggers->
+ add_tables_and_routines_for_triggers(thd, prelocking_ctx, table_list))
+ return TRUE;
+ }
+
+ if (table->file->referenced_by_foreign_key())
+ {
+ if (prepare_fk_prelocking_list(thd, prelocking_ctx, table_list,
+ need_prelocking,
+ table_list->trg_event_map))
+ return TRUE;
+ }
+ }
+ else if (table_list->slave_fk_event_map &&
+ table->file->referenced_by_foreign_key())
+ {
+ if (prepare_fk_prelocking_list(thd, prelocking_ctx, table_list,
+ need_prelocking,
+ table_list->slave_fk_event_map))
+ return TRUE;
+ }
+
+ /* Open any tables used by DEFAULT (like sequence tables) */
+ DBUG_PRINT("info", ("table: %p name: %s db: %s flags: %u",
+ table_list, table_list->table_name.str,
+ table_list->db.str, table_list->for_insert_data));
+ if (table->internal_tables &&
+ (table_list->for_insert_data ||
+ thd->lex->default_used))
+ {
+ Query_arena *arena, backup;
+ bool error;
+ arena= thd->activate_stmt_arena_if_needed(&backup);
+ error= add_internal_tables(thd, prelocking_ctx,
+ table->internal_tables);
+ if (arena)
+ thd->restore_active_arena(arena, &backup);
+ if (unlikely(error))
+ {
+ *need_prelocking= TRUE;
+ DBUG_RETURN(TRUE);
+ }
+ }
+ DBUG_RETURN(FALSE);
+}
+
+
+/**
+ Open all tables used by DEFAULT functions.
+
+ This is different from normal open_and_lock_tables() as we may
+ already have other tables opened and locked and we have to merge the
+ new table with the old ones.
+*/
+
+bool open_and_lock_internal_tables(TABLE *table, bool lock_table)
+{
+ THD *thd= table->in_use;
+ TABLE_LIST *tl;
+ MYSQL_LOCK *save_lock,*new_lock;
+ DBUG_ENTER("open_and_lock_internal_tables");
+
+ /* remove pointer to old select_lex which is already destroyed */
+ for (tl= table->internal_tables ; tl ; tl= tl->next_global)
+ tl->select_lex= 0;
+
+ uint counter;
+ MDL_savepoint mdl_savepoint= thd->mdl_context.mdl_savepoint();
+ TABLE_LIST *tmp= table->internal_tables;
+ DML_prelocking_strategy prelocking_strategy;
+
+ if (open_tables(thd, thd->lex->create_info, &tmp, &counter, 0,
+ &prelocking_strategy))
+ goto err;
+
+ if (lock_table)
+ {
+ save_lock= thd->lock;
+ thd->lock= 0;
+ if (lock_tables(thd, table->internal_tables, counter,
+ MYSQL_LOCK_USE_MALLOC))
+ goto err;
+
+ if (!(new_lock= mysql_lock_merge(save_lock, thd->lock)))
+ {
+ thd->lock= save_lock;
+ mysql_unlock_tables(thd, save_lock, 1);
+ /* We don't have to close tables as caller will do that */
+ goto err;
+ }
+ thd->lock= new_lock;
+ }
+ DBUG_RETURN(0);
+
+err:
+ thd->mdl_context.rollback_to_savepoint(mdl_savepoint);
+ DBUG_RETURN(1);
+}
+
+
+/**
+ Defines how prelocking algorithm for DML statements should handle view -
+ all view routines should be added to the prelocking set.
+
+ @param[in] thd Thread context.
+ @param[in] prelocking_ctx Prelocking context of the statement.
+ @param[in] table_list Table list element for view.
+ @param[in] sp Routine body.
+ @param[out] need_prelocking Set to TRUE if method detects that prelocking
+ required, not changed otherwise.
+
+ @retval FALSE Success.
+ @retval TRUE Failure (OOM).
+*/
+
+bool DML_prelocking_strategy::
+handle_view(THD *thd, Query_tables_list *prelocking_ctx,
+ TABLE_LIST *table_list, bool *need_prelocking)
+{
+ if (table_list->view->uses_stored_routines())
+ {
+ *need_prelocking= TRUE;
+
+ sp_update_stmt_used_routines(thd, prelocking_ctx,
+ &table_list->view->sroutines_list,
+ table_list->top_table());
+ }
+
+ /*
+ If a trigger was defined on one of the associated tables then assign the
+ 'trg_event_map' value of the view to the next table in table_list. When a
+ Stored function is invoked, all the associated tables including the tables
+ associated with the trigger are prelocked.
+ */
+ if (table_list->trg_event_map && table_list->next_global)
+ table_list->next_global->trg_event_map= table_list->trg_event_map;
+ return FALSE;
+}
+
+
+/**
+ Defines how prelocking algorithm for LOCK TABLES statement should handle
+ table list elements.
+
+ @param[in] thd Thread context.
+ @param[in] prelocking_ctx Prelocking context of the statement.
+ @param[in] table_list Table list element for table.
+ @param[in] sp Routine body.
+ @param[out] need_prelocking Set to TRUE if method detects that prelocking
+ required, not changed otherwise.
+
+ @retval FALSE Success.
+ @retval TRUE Failure (OOM).
+*/
+
+bool Lock_tables_prelocking_strategy::
+handle_table(THD *thd, Query_tables_list *prelocking_ctx,
+ TABLE_LIST *table_list, bool *need_prelocking)
+{
+ TABLE_LIST **last= prelocking_ctx->query_tables_last;
+
+ if (DML_prelocking_strategy::handle_table(thd, prelocking_ctx, table_list,
+ need_prelocking))
+ return TRUE;
+
+ /*
+ normally we don't need to open FK-prelocked tables for RESTRICT,
+ MDL is enough. But under LOCK TABLES we have to open everything
+ */
+ for (TABLE_LIST *tl= *last; tl; tl= tl->next_global)
+ tl->open_strategy= TABLE_LIST::OPEN_NORMAL;
+
+ /* We rely on a caller to check that table is going to be changed. */
+ DBUG_ASSERT(table_list->lock_type >= TL_WRITE_ALLOW_WRITE);
+
+ return FALSE;
+}
+
+
+/**
+ Defines how prelocking algorithm for ALTER TABLE statement should handle
+ routines - do nothing as this statement is not supposed to call routines.
+
+ We still can end up in this method when someone tries
+ to define a foreign key referencing a view, and not just
+ a simple view, but one that uses stored routines.
+*/
+
+bool Alter_table_prelocking_strategy::
+handle_routine(THD *thd, Query_tables_list *prelocking_ctx,
+ Sroutine_hash_entry *rt, sp_head *sp, bool *need_prelocking)
+{
+ return FALSE;
+}
+
+
+/**
+ Defines how prelocking algorithm for ALTER TABLE statement should handle
+ table list elements.
+
+ Unlike in DML, we do not process triggers here.
+
+ @param[in] thd Thread context.
+ @param[in] prelocking_ctx Prelocking context of the statement.
+ @param[in] table_list Table list element for table.
+ @param[in] sp Routine body.
+ @param[out] need_prelocking Set to TRUE if method detects that prelocking
+ required, not changed otherwise.
+
+
+ @retval FALSE Success.
+ @retval TRUE Failure (OOM).
+*/
+
+bool Alter_table_prelocking_strategy::
+handle_table(THD *thd, Query_tables_list *prelocking_ctx,
+ TABLE_LIST *table_list, bool *need_prelocking)
+{
+ return FALSE;
+}
+
+
+/**
+ Defines how prelocking algorithm for ALTER TABLE statement
+ should handle view - do nothing. We don't need to add view
+ routines to the prelocking set in this case as view is not going
+ to be materialized.
+*/
+
+bool Alter_table_prelocking_strategy::
+handle_view(THD *thd, Query_tables_list *prelocking_ctx,
+ TABLE_LIST *table_list, bool *need_prelocking)
+{
+ return FALSE;
+}
+
+
+/**
+ Check that lock is ok for tables; Call start stmt if ok
+
+ @param thd Thread handle.
+ @param prelocking_ctx Prelocking context.
+ @param table_list Table list element for table to be checked.
+
+ @retval FALSE - Ok.
+ @retval TRUE - Error.
+*/
+
+static bool check_lock_and_start_stmt(THD *thd,
+ Query_tables_list *prelocking_ctx,
+ TABLE_LIST *table_list)
+{
+ int error;
+ thr_lock_type lock_type;
+ DBUG_ENTER("check_lock_and_start_stmt");
+
+ /*
+ Prelocking placeholder is not set for TABLE_LIST that
+ are directly used by TOP level statement.
+ */
+ DBUG_ASSERT(table_list->prelocking_placeholder == TABLE_LIST::PRELOCK_NONE);
+
+ /*
+ TL_WRITE_DEFAULT and TL_READ_DEFAULT are supposed to be parser only
+ types of locks so they should be converted to appropriate other types
+ to be passed to storage engine. The exact lock type passed to the
+ engine is important as, for example, InnoDB uses it to determine
+ what kind of row locks should be acquired when executing statement
+ in prelocked mode or under LOCK TABLES with @@innodb_table_locks = 0.
+
+ Last argument routine_modifies_data for read_lock_type_for_table()
+ is ignored, as prelocking placeholder will never be set here.
+ */
+ if (table_list->lock_type == TL_WRITE_DEFAULT)
+ lock_type= thd->update_lock_default;
+ else if (table_list->lock_type == TL_READ_DEFAULT)
+ lock_type= read_lock_type_for_table(thd, prelocking_ctx, table_list, true);
+ else
+ lock_type= table_list->lock_type;
+
+ if ((int) lock_type >= (int) TL_WRITE_ALLOW_WRITE &&
+ (int) table_list->table->reginfo.lock_type < (int) TL_WRITE_ALLOW_WRITE)
+ {
+ my_error(ER_TABLE_NOT_LOCKED_FOR_WRITE, MYF(0),
+ table_list->table->alias.c_ptr());
+ DBUG_RETURN(1);
+ }
+ if (unlikely((error= table_list->table->file->start_stmt(thd, lock_type))))
+ {
+ table_list->table->file->print_error(error, MYF(0));
+ DBUG_RETURN(1);
+ }
+
+ /*
+ Record in transaction state tracking
+ */
+ TRANSACT_TRACKER(add_trx_state(thd, lock_type,
+ table_list->table->file->has_transactions()));
+
+ DBUG_RETURN(0);
+}
+
+
+/**
+ @brief Open and lock one table
+
+ @param[in] thd thread handle
+ @param[in] table_l table to open is first table in this list
+ @param[in] lock_type lock to use for table
+ @param[in] flags options to be used while opening and locking
+ table (see open_table(), mysql_lock_tables())
+ @param[in] prelocking_strategy Strategy which specifies how prelocking
+ algorithm should work for this statement.
+
+ @return table
+ @retval != NULL OK, opened table returned
+ @retval NULL Error
+
+ @note
+ If ok, the following are also set:
+ table_list->lock_type lock_type
+ table_list->table table
+
+ @note
+ If table_l is a list, not a single table, the list is temporarily
+ broken.
+
+ @detail
+ This function is meant as a replacement for open_ltable() when
+ MERGE tables can be opened. open_ltable() cannot open MERGE tables.
+
+ There may be more differences between open_n_lock_single_table() and
+ open_ltable(). One known difference is that open_ltable() does
+ neither call thd->decide_logging_format() nor handle some other logging
+ and locking issues because it does not call lock_tables().
+*/
+
+TABLE *open_n_lock_single_table(THD *thd, TABLE_LIST *table_l,
+ thr_lock_type lock_type, uint flags,
+ Prelocking_strategy *prelocking_strategy)
+{
+ TABLE_LIST *save_next_global;
+ DBUG_ENTER("open_n_lock_single_table");
+
+ /* Remember old 'next' pointer. */
+ save_next_global= table_l->next_global;
+ /* Break list. */
+ table_l->next_global= NULL;
+
+ /* Set requested lock type. */
+ table_l->lock_type= lock_type;
+ /* Allow to open real tables only. */
+ table_l->required_type= TABLE_TYPE_NORMAL;
+
+ /* Open the table. */
+ if (open_and_lock_tables(thd, table_l, FALSE, flags,
+ prelocking_strategy))
+ table_l->table= NULL; /* Just to be sure. */
+
+ /* Restore list. */
+ table_l->next_global= save_next_global;
+
+ DBUG_RETURN(table_l->table);
+}
+
+
+/*
+ Open and lock one table
+
+ SYNOPSIS
+ open_ltable()
+ thd Thread handler
+ table_list Table to open is first table in this list
+ lock_type Lock to use for open
+ lock_flags Flags passed to mysql_lock_table
+
+ NOTE
+ This function doesn't do anything like SP/SF/views/triggers analysis done
+ in open_table()/lock_tables(). It is intended for opening of only one
+ concrete table. And used only in special contexts.
+
+ RETURN VALUES
+ table Opened table
+ 0 Error
+
+ If ok, the following are also set:
+ table_list->lock_type lock_type
+ table_list->table table
+*/
+
+TABLE *open_ltable(THD *thd, TABLE_LIST *table_list, thr_lock_type lock_type,
+ uint lock_flags)
+{
+ TABLE *table;
+ Open_table_context ot_ctx(thd, lock_flags);
+ bool error;
+ DBUG_ENTER("open_ltable");
+
+ /* Ignore temporary tables as they have already been opened. */
+ if (table_list->table)
+ DBUG_RETURN(table_list->table);
+
+ /* should not be used in a prelocked_mode context, see NOTE above */
+ DBUG_ASSERT(thd->locked_tables_mode < LTM_PRELOCKED);
+
+ THD_STAGE_INFO(thd, stage_opening_tables);
+ thd->current_tablenr= 0;
+ /* open_ltable can be used only for BASIC TABLEs */
+ table_list->required_type= TABLE_TYPE_NORMAL;
+
+ /* This function can't properly handle requests for such metadata locks. */
+ DBUG_ASSERT(table_list->mdl_request.type < MDL_SHARED_UPGRADABLE);
+
+ while ((error= open_table(thd, table_list, &ot_ctx)) &&
+ ot_ctx.can_recover_from_failed_open())
+ {
+ /*
+ Even though we have failed to open table we still need to
+ call release_transactional_locks() to release metadata locks which
+ might have been acquired successfully.
+ */
+ thd->mdl_context.rollback_to_savepoint(ot_ctx.start_of_statement_svp());
+ table_list->mdl_request.ticket= 0;
+ if (ot_ctx.recover_from_failed_open())
+ break;
+ }
+
+ if (likely(!error))
+ {
+ /*
+ We can't have a view or some special "open_strategy" in this function
+ so there should be a TABLE instance.
+ */
+ DBUG_ASSERT(table_list->table);
+ table= table_list->table;
+ if (table->file->ha_table_flags() & HA_CAN_MULTISTEP_MERGE)
+ {
+ /* A MERGE table must not come here. */
+ /* purecov: begin tested */
+ my_error(ER_WRONG_OBJECT, MYF(0), table->s->db.str,
+ table->s->table_name.str, "BASE TABLE");
+ table= 0;
+ goto end;
+ /* purecov: end */
+ }
+
+ table_list->lock_type= lock_type;
+ table->grant= table_list->grant;
+ if (thd->locked_tables_mode)
+ {
+ if (check_lock_and_start_stmt(thd, thd->lex, table_list))
+ table= 0;
+ }
+ else
+ {
+ DBUG_ASSERT(thd->lock == 0); // You must lock everything at once
+ if ((table->reginfo.lock_type= lock_type) != TL_UNLOCK)
+ if (! (thd->lock= mysql_lock_tables(thd, &table_list->table, 1,
+ lock_flags)))
+ {
+ table= 0;
+ }
+ }
+ }
+ else
+ table= 0;
+
+end:
+ if (table == NULL)
+ {
+ if (!thd->in_sub_stmt)
+ trans_rollback_stmt(thd);
+ close_thread_tables(thd);
+ }
+ THD_STAGE_INFO(thd, stage_after_opening_tables);
+
+ thd_proc_info(thd, 0);
+ DBUG_RETURN(table);
+}
+
+
+/**
+ Open all tables in list, locks them and optionally process derived tables.
+
+ @param thd Thread context.
+ @param options DDL options.
+ @param tables List of tables for open and locking.
+ @param derived Whether to handle derived tables.
+ @param flags Bitmap of options to be used to open and lock
+ tables (see open_tables() and mysql_lock_tables()
+ for details).
+ @param prelocking_strategy Strategy which specifies how prelocking algorithm
+ should work for this statement.
+
+ @note
+ The thr_lock locks will automatically be freed by
+ close_thread_tables().
+
+ @retval FALSE OK.
+ @retval TRUE Error
+*/
+
+bool open_and_lock_tables(THD *thd, const DDL_options_st &options,
+ TABLE_LIST *tables,
+ bool derived, uint flags,
+ Prelocking_strategy *prelocking_strategy)
+{
+ uint counter;
+ MDL_savepoint mdl_savepoint= thd->mdl_context.mdl_savepoint();
+ DBUG_ENTER("open_and_lock_tables");
+ DBUG_PRINT("enter", ("derived handling: %d", derived));
+
+ if (open_tables(thd, options, &tables, &counter, flags, prelocking_strategy))
+ goto err;
+
+ DBUG_EXECUTE_IF("sleep_open_and_lock_after_open", {
+ const char *old_proc_info= thd->proc_info;
+ thd->proc_info= "DBUG sleep";
+ my_sleep(6000000);
+ thd->proc_info= old_proc_info;});
+
+ if (lock_tables(thd, tables, counter, flags))
+ goto err;
+
+ /* Don't read statistics tables when opening internal tables */
+ if (!(flags & MYSQL_OPEN_IGNORE_LOGGING_FORMAT))
+ (void) read_statistics_for_tables_if_needed(thd, tables);
+
+ if (derived)
+ {
+ if (mysql_handle_derived(thd->lex, DT_INIT))
+ goto err;
+ if (thd->prepare_derived_at_open &&
+ (mysql_handle_derived(thd->lex, DT_PREPARE)))
+ goto err;
+ }
+
+ DBUG_RETURN(FALSE);
+err:
+ if (! thd->in_sub_stmt)
+ trans_rollback_stmt(thd); /* Necessary if derived handling failed. */
+ close_thread_tables(thd);
+ /* Don't keep locks for a failed statement. */
+ thd->mdl_context.rollback_to_savepoint(mdl_savepoint);
+ DBUG_RETURN(TRUE);
+}
+
+
+/*
+ Open all tables in list and process derived tables
+
+ SYNOPSIS
+ open_normal_and_derived_tables
+ thd - thread handler
+ tables - list of tables for open
+ flags - bitmap of flags to modify how the tables will be open:
+ MYSQL_LOCK_IGNORE_FLUSH - open table even if someone has
+ done a flush on it.
+ dt_phases - set of flags to pass to the mysql_handle_derived
+
+ RETURN
+ FALSE - ok
+ TRUE - error
+
+ NOTE
+ This is to be used on prepare stage when you don't read any
+ data from the tables.
+*/
+
+bool open_normal_and_derived_tables(THD *thd, TABLE_LIST *tables, uint flags,
+ uint dt_phases)
+{
+ DML_prelocking_strategy prelocking_strategy;
+ uint counter;
+ MDL_savepoint mdl_savepoint= thd->mdl_context.mdl_savepoint();
+ DBUG_ENTER("open_normal_and_derived_tables");
+ if (open_tables(thd, &tables, &counter, flags, &prelocking_strategy) ||
+ mysql_handle_derived(thd->lex, dt_phases))
+ goto end;
+
+ DBUG_RETURN(0);
+end:
+ /*
+ No need to commit/rollback the statement transaction: it's
+ either not started or we're filling in an INFORMATION_SCHEMA
+ table on the fly, and thus mustn't manipulate with the
+ transaction of the enclosing statement.
+ */
+ DBUG_ASSERT(thd->transaction->stmt.is_empty() ||
+ (thd->state_flags & Open_tables_state::BACKUPS_AVAIL));
+ close_thread_tables(thd);
+ /* Don't keep locks for a failed statement. */
+ thd->mdl_context.rollback_to_savepoint(mdl_savepoint);
+
+ DBUG_RETURN(TRUE); /* purecov: inspected */
+}
+
+
+/**
+ Open a table to read its structure, e.g. for:
+ - SHOW FIELDS
+ - delayed SP variable data type definition: DECLARE a t1.a%TYPE
+
+ The flag MYSQL_OPEN_GET_NEW_TABLE is passed to make %TYPE work
+ in stored functions, as during a stored function call
+ (e.g. in a SELECT query) the tables referenced in %TYPE can already be locked,
+ and attempt to open it again would return an error in open_table().
+
+ The flag MYSQL_OPEN_GET_NEW_TABLE is not really needed for
+ SHOW FIELDS or for a "CALL sp()" statement, but it's not harmful,
+ so let's pass it unconditionally.
+*/
+
+bool open_tables_only_view_structure(THD *thd, TABLE_LIST *table_list,
+ bool can_deadlock)
+{
+ DBUG_ENTER("open_tables_only_view_structure");
+ /*
+ Let us set fake sql_command so views won't try to merge
+ themselves into main statement. If we don't do this,
+ SELECT * from information_schema.xxxx will cause problems.
+ SQLCOM_SHOW_FIELDS is used because it satisfies
+ 'LEX::only_view_structure()'.
+ */
+ enum_sql_command save_sql_command= thd->lex->sql_command;
+ thd->lex->sql_command= SQLCOM_SHOW_FIELDS;
+ bool rc= (thd->open_temporary_tables(table_list) ||
+ open_normal_and_derived_tables(thd, table_list,
+ (MYSQL_OPEN_IGNORE_FLUSH |
+ MYSQL_OPEN_FORCE_SHARED_HIGH_PRIO_MDL |
+ MYSQL_OPEN_GET_NEW_TABLE |
+ (can_deadlock ?
+ MYSQL_OPEN_FAIL_ON_MDL_CONFLICT : 0)),
+ DT_INIT | DT_PREPARE));
+ /*
+ Restore old value of sql_command back as it is being looked at in
+ process_table() function.
+ */
+ thd->lex->sql_command= save_sql_command;
+ DBUG_RETURN(rc);
+}
+
+
+/*
+ Mark all real tables in the list as free for reuse.
+
+ SYNOPSIS
+ mark_real_tables_as_free_for_reuse()
+ thd - thread context
+ table - head of the list of tables
+
+ DESCRIPTION
+ Marks all real tables in the list (i.e. not views, derived
+ or schema tables) as free for reuse.
+*/
+
+static void mark_real_tables_as_free_for_reuse(TABLE_LIST *table_list)
+{
+ TABLE_LIST *table;
+ DBUG_ENTER("mark_real_tables_as_free_for_reuse");
+
+ /*
+ We have to make two loops as HA_EXTRA_DETACH_CHILDREN may
+ remove items from the table list that we have to reset
+ */
+ for (table= table_list; table; table= table->next_global)
+ {
+ if (!table->placeholder())
+ table->table->query_id= 0;
+ }
+ for (table= table_list; table; table= table->next_global)
+ {
+ if (!table->placeholder())
+ {
+ /*
+ Detach children of MyISAMMRG tables used in
+ sub-statements, they will be reattached at open.
+ This has to be done in a separate loop to make sure
+ that children have had their query_id cleared.
+ */
+ table->table->file->extra(HA_EXTRA_DETACH_CHILDREN);
+ }
+ }
+ DBUG_VOID_RETURN;
+}
+
+int TABLE::fix_vcol_exprs(THD *thd)
+{
+ for (Field **vf= vfield; vf && *vf; vf++)
+ if (fix_session_vcol_expr(thd, (*vf)->vcol_info))
+ return 1;
+
+ for (Field **df= default_field; df && *df; df++)
+ if ((*df)->default_value &&
+ fix_session_vcol_expr(thd, (*df)->default_value))
+ return 1;
+
+ for (Virtual_column_info **cc= check_constraints; cc && *cc; cc++)
+ if (fix_session_vcol_expr(thd, (*cc)))
+ return 1;
+
+ return 0;
+}
+
+
+static bool fix_all_session_vcol_exprs(THD *thd, TABLE_LIST *tables)
+{
+ Security_context *save_security_ctx= thd->security_ctx;
+ TABLE_LIST *first_not_own= thd->lex->first_not_own_table();
+ DBUG_ENTER("fix_session_vcol_expr");
+
+ int error= 0;
+ for (TABLE_LIST *table= tables; table && table != first_not_own && !error;
+ table= table->next_global)
+ {
+ TABLE *t= table->table;
+ if (!table->placeholder() && t->s->vcols_need_refixing &&
+ table->lock_type >= TL_WRITE_ALLOW_WRITE)
+ {
+ Query_arena *stmt_backup= thd->stmt_arena;
+ if (thd->stmt_arena->is_conventional())
+ thd->stmt_arena= t->expr_arena;
+ if (table->security_ctx)
+ thd->security_ctx= table->security_ctx;
+
+ error= t->fix_vcol_exprs(thd);
+
+ thd->security_ctx= save_security_ctx;
+ thd->stmt_arena= stmt_backup;
+ }
+ }
+ DBUG_RETURN(error);
+}
+
+
+/**
+ Lock all tables in a list.
+
+ @param thd Thread handler
+ @param tables Tables to lock
+ @param count Number of opened tables
+ @param flags Options (see mysql_lock_tables() for details)
+
+ You can't call lock_tables() while holding thr_lock locks, as
+ this would break the dead-lock-free handling thr_lock gives us.
+ You must always get all needed locks at once.
+
+ If the query for which we are calling this function is marked as
+ requiring prelocking, this function will change
+ locked_tables_mode to LTM_PRELOCKED.
+
+ @retval FALSE Success.
+ @retval TRUE A lock wait timeout, deadlock or out of memory.
+*/
+
+bool lock_tables(THD *thd, TABLE_LIST *tables, uint count, uint flags)
+{
+ TABLE_LIST *table, *first_not_own;
+ DBUG_ENTER("lock_tables");
+ /*
+ We can't meet statement requiring prelocking if we already
+ in prelocked mode.
+ */
+ DBUG_ASSERT(thd->locked_tables_mode <= LTM_LOCK_TABLES ||
+ !thd->lex->requires_prelocking());
+
+ if (!tables && !thd->lex->requires_prelocking())
+ DBUG_RETURN(0);
+
+ first_not_own= thd->lex->first_not_own_table();
+
+ /*
+ Check for thd->locked_tables_mode to avoid a redundant
+ and harmful attempt to lock the already locked tables again.
+ Checking for thd->lock is not enough in some situations. For example,
+ if a stored function contains
+ "drop table t3; create temporary t3 ..; insert into t3 ...;"
+ thd->lock may be 0 after drop tables, whereas locked_tables_mode
+ is still on. In this situation an attempt to lock temporary
+ table t3 will lead to a memory leak.
+ */
+ if (! thd->locked_tables_mode)
+ {
+ DBUG_ASSERT(thd->lock == 0); // You must lock everything at once
+ TABLE **start,**ptr;
+ bool found_first_not_own= 0;
+
+ if (!(ptr=start=(TABLE**) thd->alloc(sizeof(TABLE*)*count)))
+ DBUG_RETURN(TRUE);
+
+ /*
+ Collect changes tables for table lock.
+ Mark own tables with query id as this is needed by
+ prepare_for_row_logging()
+ */
+ for (table= tables; table; table= table->next_global)
+ {
+ if (table == first_not_own)
+ found_first_not_own= 1;
+ if (!table->placeholder())
+ {
+ *(ptr++)= table->table;
+ if (!found_first_not_own)
+ table->table->query_id= thd->query_id;
+ }
+ }
+
+ DEBUG_SYNC(thd, "before_lock_tables_takes_lock");
+
+ if (! (thd->lock= mysql_lock_tables(thd, start, (uint) (ptr - start),
+ flags)))
+ DBUG_RETURN(TRUE);
+
+ DEBUG_SYNC(thd, "after_lock_tables_takes_lock");
+
+ if (thd->lex->requires_prelocking() &&
+ thd->lex->sql_command != SQLCOM_LOCK_TABLES)
+ {
+ /*
+ We just have done implicit LOCK TABLES, and now we have
+ to emulate first open_and_lock_tables() after it.
+
+ When open_and_lock_tables() is called for a single table out of
+ a table list, the 'next_global' chain is temporarily broken. We
+ may not find 'first_not_own' before the end of the "list".
+ Look for example at those places where open_n_lock_single_table()
+ is called. That function implements the temporary breaking of
+ a table list for opening a single table.
+ */
+ for (table= tables;
+ table && table != first_not_own;
+ table= table->next_global)
+ {
+ if (!table->placeholder())
+ {
+ if (check_lock_and_start_stmt(thd, thd->lex, table))
+ {
+ mysql_unlock_tables(thd, thd->lock);
+ thd->lock= 0;
+ DBUG_RETURN(TRUE);
+ }
+ }
+ }
+ /*
+ Let us mark all tables which don't belong to the statement itself,
+ and was marked as occupied during open_tables() as free for reuse.
+ */
+ mark_real_tables_as_free_for_reuse(first_not_own);
+ DBUG_PRINT("info",("locked_tables_mode= LTM_PRELOCKED"));
+ thd->enter_locked_tables_mode(LTM_PRELOCKED);
+ }
+ }
+ else
+ {
+ /*
+ When open_and_lock_tables() is called for a single table out of
+ a table list, the 'next_global' chain is temporarily broken. We
+ may not find 'first_not_own' before the end of the "list".
+ Look for example at those places where open_n_lock_single_table()
+ is called. That function implements the temporary breaking of
+ a table list for opening a single table.
+ */
+ for (table= tables;
+ table && table != first_not_own;
+ table= table->next_global)
+ {
+ if (table->placeholder())
+ continue;
+
+ table->table->query_id= thd->query_id;
+ /*
+ In a stored function or trigger we should ensure that we won't change
+ a table that is already used by the calling statement.
+ */
+ if (thd->locked_tables_mode >= LTM_PRELOCKED &&
+ table->lock_type >= TL_WRITE_ALLOW_WRITE)
+ {
+ for (TABLE* opentab= thd->open_tables; opentab; opentab= opentab->next)
+ {
+ if (table->table->s == opentab->s && opentab->query_id &&
+ table->table->query_id != opentab->query_id)
+ {
+ my_error(ER_CANT_UPDATE_USED_TABLE_IN_SF_OR_TRG, MYF(0),
+ table->table->s->table_name.str);
+ DBUG_RETURN(TRUE);
+ }
+ }
+ }
+
+ if (check_lock_and_start_stmt(thd, thd->lex, table))
+ {
+ DBUG_RETURN(TRUE);
+ }
+ }
+ /*
+ If we are under explicit LOCK TABLES and our statement requires
+ prelocking, we should mark all "additional" tables as free for use
+ and enter prelocked mode.
+ */
+ if (thd->lex->requires_prelocking())
+ {
+ mark_real_tables_as_free_for_reuse(first_not_own);
+ DBUG_PRINT("info",
+ ("thd->locked_tables_mode= LTM_PRELOCKED_UNDER_LOCK_TABLES"));
+ thd->locked_tables_mode= LTM_PRELOCKED_UNDER_LOCK_TABLES;
+ }
+ }
+
+ bool res= fix_all_session_vcol_exprs(thd, tables);
+ if (!res && !(flags & MYSQL_OPEN_IGNORE_LOGGING_FORMAT))
+ res= thd->decide_logging_format(tables);
+
+ DBUG_RETURN(res);
+}
+
+
+/*
+ Restart transaction for tables
+
+ This is used when we had to do an implicit commit after tables are opened
+ and want to restart transactions on tables.
+
+ This is used in case of:
+ LOCK TABLES xx
+ CREATE OR REPLACE TABLE xx;
+*/
+
+bool restart_trans_for_tables(THD *thd, TABLE_LIST *table)
+{
+ DBUG_ENTER("restart_trans_for_tables");
+
+ for (; table; table= table->next_global)
+ {
+ if (table->placeholder())
+ continue;
+
+ if (check_lock_and_start_stmt(thd, thd->lex, table))
+ {
+ DBUG_ASSERT(0); // Should never happen
+ DBUG_RETURN(TRUE);
+ }
+ }
+ DBUG_RETURN(FALSE);
+}
+
+
+/**
+ Prepare statement for reopening of tables and recalculation of set of
+ prelocked tables.
+
+ @param[in] thd Thread context.
+ @param[in,out] tables List of tables which we were trying to open
+ and lock.
+ @param[in] start_of_statement_svp MDL savepoint which represents the set
+ of metadata locks which the current transaction
+ managed to acquire before execution of the current
+ statement and to which we should revert before
+ trying to reopen tables. NULL if no metadata locks
+ were held and thus all metadata locks should be
+ released.
+*/
+
+void close_tables_for_reopen(THD *thd, TABLE_LIST **tables,
+ const MDL_savepoint &start_of_statement_svp)
+{
+ TABLE_LIST *first_not_own_table= thd->lex->first_not_own_table();
+ TABLE_LIST *tmp;
+
+ /*
+ If table list consists only from tables from prelocking set, table list
+ for new attempt should be empty, so we have to update list's root pointer.
+ */
+ if (first_not_own_table == *tables)
+ *tables= 0;
+ thd->lex->chop_off_not_own_tables();
+ /* Reset MDL tickets for procedures/functions */
+ for (Sroutine_hash_entry *rt=
+ (Sroutine_hash_entry*)thd->lex->sroutines_list.first;
+ rt; rt= rt->next)
+ rt->mdl_request.ticket= NULL;
+ sp_remove_not_own_routines(thd->lex);
+ for (tmp= *tables; tmp; tmp= tmp->next_global)
+ {
+ tmp->table= 0;
+ tmp->mdl_request.ticket= NULL;
+ /* We have to cleanup translation tables of views. */
+ tmp->cleanup_items();
+ }
+ /*
+ No need to commit/rollback the statement transaction: it's
+ either not started or we're filling in an INFORMATION_SCHEMA
+ table on the fly, and thus mustn't manipulate with the
+ transaction of the enclosing statement.
+ */
+ DBUG_ASSERT(thd->transaction->stmt.is_empty() ||
+ (thd->state_flags & Open_tables_state::BACKUPS_AVAIL));
+ close_thread_tables(thd);
+ thd->mdl_context.rollback_to_savepoint(start_of_statement_svp);
+}
+
+
+/*****************************************************************************
+* The following find_field_in_XXX procedures implement the core of the
+* name resolution functionality. The entry point to resolve a column name in a
+* list of tables is 'find_field_in_tables'. It calls 'find_field_in_table_ref'
+* for each table reference. In turn, depending on the type of table reference,
+* 'find_field_in_table_ref' calls one of the 'find_field_in_XXX' procedures
+* below specific for the type of table reference.
+******************************************************************************/
+
+/* Special Field pointers as return values of find_field_in_XXX functions. */
+Field *not_found_field= (Field*) 0x1;
+Field *view_ref_found= (Field*) 0x2;
+
+#define WRONG_GRANT (Field*) -1
+
+static void update_field_dependencies(THD *thd, Field *field, TABLE *table)
+{
+ DBUG_ENTER("update_field_dependencies");
+ if (should_mark_column(thd->column_usage))
+ {
+ /*
+ We always want to register the used keys, as the column bitmap may have
+ been set for all fields (for example for view).
+ */
+ table->covering_keys.intersect(field->part_of_key);
+
+ if (thd->column_usage == MARK_COLUMNS_READ)
+ {
+ if (table->mark_column_with_deps(field))
+ DBUG_VOID_RETURN; // Field was already marked
+ }
+ else
+ {
+ if (bitmap_fast_test_and_set(table->write_set, field->field_index))
+ {
+ DBUG_PRINT("warning", ("Found duplicated field"));
+ thd->dup_field= field;
+ DBUG_VOID_RETURN;
+ }
+ }
+
+ table->used_fields++;
+ }
+ if (table->get_fields_in_item_tree)
+ field->flags|= GET_FIXED_FIELDS_FLAG;
+ DBUG_VOID_RETURN;
+}
+
+
+/*
+ Find a field by name in a view that uses merge algorithm.
+
+ SYNOPSIS
+ find_field_in_view()
+ thd thread handler
+ table_list view to search for 'name'
+ name name of field
+ length length of name
+ item_name name of item if it will be created (VIEW)
+ ref expression substituted in VIEW should be passed
+ using this reference (return view_ref_found)
+ register_tree_change TRUE if ref is not stack variable and we
+ need register changes in item tree
+
+ RETURN
+ 0 field is not found
+ view_ref_found found value in VIEW (real result is in *ref)
+ # pointer to field - only for schema table fields
+*/
+
+static Field *
+find_field_in_view(THD *thd, TABLE_LIST *table_list,
+ const char *name, size_t length,
+ const char *item_name, Item **ref,
+ bool register_tree_change)
+{
+ DBUG_ENTER("find_field_in_view");
+ DBUG_PRINT("enter",
+ ("view: '%s', field name: '%s', item name: '%s', ref %p",
+ table_list->alias.str, name, item_name, ref));
+ Field_iterator_view field_it;
+ field_it.set(table_list);
+ Query_arena *arena= 0, backup;
+
+ for (; !field_it.end_of_fields(); field_it.next())
+ {
+ if (!my_strcasecmp(system_charset_info, field_it.name()->str, name))
+ {
+ // in PS use own arena or data will be freed after prepare
+ if (register_tree_change &&
+ thd->stmt_arena->is_stmt_prepare_or_first_stmt_execute())
+ arena= thd->activate_stmt_arena_if_needed(&backup);
+ /*
+ create_item() may, or may not create a new Item, depending on
+ the column reference. See create_view_field() for details.
+ */
+ Item *item= field_it.create_item(thd);
+ if (arena)
+ thd->restore_active_arena(arena, &backup);
+
+ if (!item)
+ DBUG_RETURN(0);
+ if (!ref)
+ DBUG_RETURN((Field*) view_ref_found);
+ /*
+ *ref != NULL means that *ref contains the item that we need to
+ replace. If the item was aliased by the user, set the alias to
+ the replacing item.
+ */
+ if (*ref && !(*ref)->is_autogenerated_name())
+ item->set_name(thd, (*ref)->name);
+ if (register_tree_change)
+ thd->change_item_tree(ref, item);
+ else
+ *ref= item;
+ DBUG_RETURN((Field*) view_ref_found);
+ }
+ }
+ DBUG_RETURN(0);
+}
+
+
+/*
+ Find field by name in a NATURAL/USING join table reference.
+
+ SYNOPSIS
+ find_field_in_natural_join()
+ thd [in] thread handler
+ table_ref [in] table reference to search
+ name [in] name of field
+ length [in] length of name
+ ref [in/out] if 'name' is resolved to a view field, ref is
+ set to point to the found view field
+ register_tree_change [in] TRUE if ref is not stack variable and we
+ need register changes in item tree
+ actual_table [out] the original table reference where the field
+ belongs - differs from 'table_list' only for
+ NATURAL/USING joins
+
+ DESCRIPTION
+ Search for a field among the result fields of a NATURAL/USING join.
+ Notice that this procedure is called only for non-qualified field
+ names. In the case of qualified fields, we search directly the base
+ tables of a natural join.
+
+ RETURN
+ NULL if the field was not found
+ WRONG_GRANT if no access rights to the found field
+ # Pointer to the found Field
+*/
+
+static Field *
+find_field_in_natural_join(THD *thd, TABLE_LIST *table_ref, const char *name, size_t length, Item **ref, bool register_tree_change,
+ TABLE_LIST **actual_table)
+{
+ List_iterator_fast<Natural_join_column>
+ field_it(*(table_ref->join_columns));
+ Natural_join_column *nj_col, *curr_nj_col;
+ Field *UNINIT_VAR(found_field);
+ Query_arena *UNINIT_VAR(arena), backup;
+ DBUG_ENTER("find_field_in_natural_join");
+ DBUG_PRINT("enter", ("field name: '%s', ref %p",
+ name, ref));
+ DBUG_ASSERT(table_ref->is_natural_join && table_ref->join_columns);
+ DBUG_ASSERT(*actual_table == NULL);
+
+ for (nj_col= NULL, curr_nj_col= field_it++; curr_nj_col;
+ curr_nj_col= field_it++)
+ {
+ if (!my_strcasecmp(system_charset_info, curr_nj_col->name()->str, name))
+ {
+ if (nj_col)
+ {
+ my_error(ER_NON_UNIQ_ERROR, MYF(0), name, thd->where);
+ DBUG_RETURN(NULL);
+ }
+ nj_col= curr_nj_col;
+ }
+ }
+ if (!nj_col)
+ DBUG_RETURN(NULL);
+
+ if (nj_col->view_field)
+ {
+ Item *item;
+ if (register_tree_change)
+ arena= thd->activate_stmt_arena_if_needed(&backup);
+ /*
+ create_item() may, or may not create a new Item, depending on the
+ column reference. See create_view_field() for details.
+ */
+ item= nj_col->create_item(thd);
+ if (!item)
+ DBUG_RETURN(NULL);
+
+ /*
+ *ref != NULL means that *ref contains the item that we need to
+ replace. If the item was aliased by the user, set the alias to
+ the replacing item.
+ */
+ if (*ref && !(*ref)->is_autogenerated_name())
+ item->set_name(thd, (*ref)->name);
+ if (register_tree_change && arena)
+ thd->restore_active_arena(arena, &backup);
+
+ if (!item)
+ DBUG_RETURN(NULL);
+ DBUG_ASSERT(nj_col->table_field == NULL);
+ if (nj_col->table_ref->schema_table_reformed)
+ {
+ /*
+ Translation table items are always Item_fields and fixed
+ already('mysql_schema_table' function). So we can return
+ ->field. It is used only for 'show & where' commands.
+ */
+ DBUG_RETURN(((Item_field*) (nj_col->view_field->item))->field);
+ }
+ if (register_tree_change)
+ thd->change_item_tree(ref, item);
+ else
+ *ref= item;
+ found_field= (Field*) view_ref_found;
+ }
+ else
+ {
+ /* This is a base table. */
+ DBUG_ASSERT(nj_col->view_field == NULL);
+ Item *ref= 0;
+ /*
+ This fix_fields is not necessary (initially this item is fixed by
+ the Item_field constructor; after reopen_tables the Item_func_eq
+ calls fix_fields on that item), it's just a check during table
+ reopening for columns that was dropped by the concurrent connection.
+ */
+ if (nj_col->table_field->fix_fields_if_needed(thd, &ref))
+ {
+ DBUG_PRINT("info", ("column '%s' was dropped by the concurrent connection",
+ nj_col->table_field->name.str));
+ DBUG_RETURN(NULL);
+ }
+ DBUG_ASSERT(ref == 0); // Should not have changed
+ DBUG_ASSERT(nj_col->table_ref->table == nj_col->table_field->field->table);
+ found_field= nj_col->table_field->field;
+ update_field_dependencies(thd, found_field, nj_col->table_ref->table);
+ }
+
+ *actual_table= nj_col->table_ref;
+
+ DBUG_RETURN(found_field);
+}
+
+
+/*
+ Find field by name in a base table or a view with temp table algorithm.
+
+ The caller is expected to check column-level privileges.
+
+ SYNOPSIS
+ find_field_in_table()
+ thd thread handler
+ table table where to search for the field
+ name name of field
+ length length of name
+ allow_rowid do allow finding of "_rowid" field?
+ cached_field_index_ptr cached position in field list (used to speedup
+ lookup for fields in prepared tables)
+
+ RETURN
+ 0 field is not found
+ # pointer to field
+*/
+
+Field *
+find_field_in_table(THD *thd, TABLE *table, const char *name, size_t length,
+ bool allow_rowid, uint *cached_field_index_ptr)
+{
+ Field *field;
+ uint cached_field_index= *cached_field_index_ptr;
+ DBUG_ENTER("find_field_in_table");
+ DBUG_PRINT("enter", ("table: '%s', field name: '%s'", table->alias.c_ptr(),
+ name));
+
+ /* We assume here that table->field < NO_CACHED_FIELD_INDEX = UINT_MAX */
+ if (cached_field_index < table->s->fields &&
+ !my_strcasecmp(system_charset_info,
+ table->field[cached_field_index]->field_name.str, name))
+ field= table->field[cached_field_index];
+ else
+ {
+ LEX_CSTRING fname= {name, length};
+ field= table->find_field_by_name(&fname);
+ }
+
+ if (field)
+ {
+ if (field->invisible == INVISIBLE_FULL &&
+ DBUG_EVALUATE_IF("test_completely_invisible", 0, 1))
+ DBUG_RETURN((Field*)0);
+
+ if (field->invisible == INVISIBLE_SYSTEM &&
+ thd->column_usage != MARK_COLUMNS_READ &&
+ thd->column_usage != COLUMNS_READ)
+ DBUG_RETURN((Field*)0);
+ }
+ else
+ {
+ if (!allow_rowid ||
+ my_strcasecmp(system_charset_info, name, "_rowid") ||
+ table->s->rowid_field_offset == 0)
+ DBUG_RETURN((Field*) 0);
+ field= table->field[table->s->rowid_field_offset-1];
+ }
+ *cached_field_index_ptr= field->field_index;
+
+ update_field_dependencies(thd, field, table);
+
+ DBUG_RETURN(field);
+}
+
+
+/*
+ Find field in a table reference.
+
+ SYNOPSIS
+ find_field_in_table_ref()
+ thd [in] thread handler
+ table_list [in] table reference to search
+ name [in] name of field
+ length [in] field length of name
+ item_name [in] name of item if it will be created (VIEW)
+ db_name [in] optional database name that qualifies the
+ table_name [in] optional table name that qualifies the field
+ 0 for non-qualified field in natural joins
+ ref [in/out] if 'name' is resolved to a view field, ref
+ is set to point to the found view field
+ check_privileges [in] check privileges
+ allow_rowid [in] do allow finding of "_rowid" field?
+ cached_field_index_ptr [in] cached position in field list (used to
+ speedup lookup for fields in prepared tables)
+ register_tree_change [in] TRUE if ref is not stack variable and we
+ need register changes in item tree
+ actual_table [out] the original table reference where the field
+ belongs - differs from 'table_list' only for
+ NATURAL_USING joins.
+
+ DESCRIPTION
+ Find a field in a table reference depending on the type of table
+ reference. There are three types of table references with respect
+ to the representation of their result columns:
+ - an array of Field_translator objects for MERGE views and some
+ information_schema tables,
+ - an array of Field objects (and possibly a name hash) for stored
+ tables,
+ - a list of Natural_join_column objects for NATURAL/USING joins.
+ This procedure detects the type of the table reference 'table_list'
+ and calls the corresponding search routine.
+
+ The routine checks column-level privieleges for the found field.
+
+ RETURN
+ 0 field is not found
+ view_ref_found found value in VIEW (real result is in *ref)
+ # pointer to field
+*/
+
+Field *
+find_field_in_table_ref(THD *thd, TABLE_LIST *table_list,
+ const char *name, size_t length,
+ const char *item_name, const char *db_name,
+ const char *table_name, Item **ref,
+ bool check_privileges, bool allow_rowid,
+ uint *cached_field_index_ptr,
+ bool register_tree_change, TABLE_LIST **actual_table)
+{
+ Field *fld;
+ DBUG_ENTER("find_field_in_table_ref");
+ DBUG_ASSERT(table_list->alias.str);
+ DBUG_ASSERT(name);
+ DBUG_ASSERT(item_name);
+ DBUG_PRINT("enter",
+ ("table: '%s' field name: '%s' item name: '%s' ref %p",
+ table_list->alias.str, name, item_name, ref));
+
+ /*
+ Check that the table and database that qualify the current field name
+ are the same as the table reference we are going to search for the field.
+
+ Exclude from the test below nested joins because the columns in a
+ nested join generally originate from different tables. Nested joins
+ also have no table name, except when a nested join is a merge view
+ or an information schema table.
+
+ We include explicitly table references with a 'field_translation' table,
+ because if there are views over natural joins we don't want to search
+ inside the view, but we want to search directly in the view columns
+ which are represented as a 'field_translation'.
+
+ tables->db.str may be 0 if we are preparing a statement
+ db_name is 0 if item doesn't have a db name
+ table_name is 0 if item doesn't have a specified table_name
+ */
+ if (db_name && !db_name[0])
+ db_name= 0; // Simpler test later
+
+ if (/* Exclude nested joins. */
+ (!table_list->nested_join ||
+ /* Include merge views and information schema tables. */
+ table_list->field_translation) &&
+ /*
+ Test if the field qualifiers match the table reference we plan
+ to search.
+ */
+ table_name && table_name[0] &&
+ (my_strcasecmp(table_alias_charset, table_list->alias.str, table_name) ||
+ (db_name && (!table_list->db.str || !table_list->db.str[0])) ||
+ (db_name && table_list->db.str && table_list->db.str[0] &&
+ (table_list->schema_table ?
+ my_strcasecmp(system_charset_info, db_name, table_list->db.str) :
+ strcmp(db_name, table_list->db.str)))))
+ DBUG_RETURN(0);
+
+ /*
+ Don't allow usage of fields in sequence table that is opened as part of
+ NEXT VALUE for sequence_name
+ */
+ if (table_list->sequence)
+ DBUG_RETURN(0);
+
+ *actual_table= NULL;
+
+ if (table_list->field_translation)
+ {
+ /* 'table_list' is a view or an information schema table. */
+ if ((fld= find_field_in_view(thd, table_list, name, length, item_name, ref,
+ register_tree_change)))
+ *actual_table= table_list;
+ }
+ else if (!table_list->nested_join)
+ {
+ /* 'table_list' is a stored table. */
+ DBUG_ASSERT(table_list->table);
+ if ((fld= find_field_in_table(thd, table_list->table, name, length,
+ allow_rowid,
+ cached_field_index_ptr)))
+ *actual_table= table_list;
+ }
+ else
+ {
+ /*
+ 'table_list' is a NATURAL/USING join, or an operand of such join that
+ is a nested join itself.
+
+ If the field name we search for is qualified, then search for the field
+ in the table references used by NATURAL/USING the join.
+ */
+ if (table_name && table_name[0])
+ {
+ List_iterator<TABLE_LIST> it(table_list->nested_join->join_list);
+ TABLE_LIST *table;
+ while ((table= it++))
+ {
+ if ((fld= find_field_in_table_ref(thd, table, name, length, item_name,
+ db_name, table_name, ref,
+ check_privileges, allow_rowid,
+ cached_field_index_ptr,
+ register_tree_change, actual_table)))
+ DBUG_RETURN(fld);
+ }
+ DBUG_RETURN(0);
+ }
+ /*
+ Non-qualified field, search directly in the result columns of the
+ natural join. The condition of the outer IF is true for the top-most
+ natural join, thus if the field is not qualified, we will search
+ directly the top-most NATURAL/USING join.
+ */
+ fld= find_field_in_natural_join(thd, table_list, name, length, ref,
+ register_tree_change, actual_table);
+ }
+
+ if (fld)
+ {
+#ifndef NO_EMBEDDED_ACCESS_CHECKS
+ /* Check if there are sufficient access rights to the found field. */
+ if (check_privileges &&
+ !table_list->is_derived() &&
+ check_column_grant_in_table_ref(thd, *actual_table, name, length, fld))
+ fld= WRONG_GRANT;
+ else
+#endif
+ if (should_mark_column(thd->column_usage))
+ {
+ /*
+ Get rw_set correct for this field so that the handler
+ knows that this field is involved in the query and gets
+ retrieved/updated
+ */
+ Field *field_to_set= NULL;
+ if (fld == view_ref_found)
+ {
+ if (!ref)
+ DBUG_RETURN(fld);
+ Item *it= (*ref)->real_item();
+ if (it->type() == Item::FIELD_ITEM)
+ field_to_set= ((Item_field*)it)->field;
+ else
+ {
+ if (thd->column_usage == MARK_COLUMNS_READ)
+ it->walk(&Item::register_field_in_read_map, 0, 0);
+ else
+ it->walk(&Item::register_field_in_write_map, 0, 0);
+ }
+ }
+ else
+ field_to_set= fld;
+ if (field_to_set)
+ {
+ TABLE *table= field_to_set->table;
+ DBUG_ASSERT(table);
+ if (thd->column_usage == MARK_COLUMNS_READ)
+ field_to_set->register_field_in_read_map();
+ else
+ bitmap_set_bit(table->write_set, field_to_set->field_index);
+ }
+ }
+ }
+ DBUG_RETURN(fld);
+}
+
+
+/*
+ Find field in table, no side effects, only purpose is to check for field
+ in table object and get reference to the field if found.
+
+ SYNOPSIS
+ find_field_in_table_sef()
+
+ table table where to find
+ name Name of field searched for
+
+ RETURN
+ 0 field is not found
+ # pointer to field
+*/
+
+Field *find_field_in_table_sef(TABLE *table, const char *name)
+{
+ Field **field_ptr;
+ if (table->s->name_hash.records)
+ {
+ field_ptr= (Field**)my_hash_search(&table->s->name_hash,(uchar*) name,
+ strlen(name));
+ if (field_ptr)
+ {
+ /*
+ field_ptr points to field in TABLE_SHARE. Convert it to the matching
+ field in table
+ */
+ field_ptr= (table->field + (field_ptr - table->s->field));
+ }
+ }
+ else
+ {
+ if (!(field_ptr= table->field))
+ return (Field *)0;
+ for (; *field_ptr; ++field_ptr)
+ if (!my_strcasecmp(system_charset_info, (*field_ptr)->field_name.str,
+ name))
+ break;
+ }
+ if (field_ptr)
+ return *field_ptr;
+ else
+ return (Field *)0;
+}
+
+
+/*
+ Find field in table list.
+
+ SYNOPSIS
+ find_field_in_tables()
+ thd pointer to current thread structure
+ item field item that should be found
+ first_table list of tables to be searched for item
+ last_table end of the list of tables to search for item. If NULL
+ then search to the end of the list 'first_table'.
+ ref if 'item' is resolved to a view field, ref is set to
+ point to the found view field
+ report_error Degree of error reporting:
+ - IGNORE_ERRORS then do not report any error
+ - IGNORE_EXCEPT_NON_UNIQUE report only non-unique
+ fields, suppress all other errors
+ - REPORT_EXCEPT_NON_UNIQUE report all other errors
+ except when non-unique fields were found
+ - REPORT_ALL_ERRORS
+ check_privileges need to check privileges
+ register_tree_change TRUE if ref is not a stack variable and we
+ to need register changes in item tree
+
+ RETURN VALUES
+ 0 If error: the found field is not unique, or there are
+ no sufficient access priviliges for the found field,
+ or the field is qualified with non-existing table.
+ not_found_field The function was called with report_error ==
+ (IGNORE_ERRORS || IGNORE_EXCEPT_NON_UNIQUE) and a
+ field was not found.
+ view_ref_found View field is found, item passed through ref parameter
+ found field If a item was resolved to some field
+*/
+
+Field *
+find_field_in_tables(THD *thd, Item_ident *item,
+ TABLE_LIST *first_table, TABLE_LIST *last_table,
+ Item **ref, find_item_error_report_type report_error,
+ bool check_privileges, bool register_tree_change)
+{
+ Field *found=0;
+ const char *db= item->db_name.str;
+ const char *table_name= item->table_name.str;
+ const char *name= item->field_name.str;
+ size_t length= item->field_name.length;
+ char name_buff[SAFE_NAME_LEN+1];
+ TABLE_LIST *cur_table= first_table;
+ TABLE_LIST *actual_table;
+ bool allow_rowid;
+
+ if (!table_name || !table_name[0])
+ {
+ table_name= 0; // For easier test
+ db= 0;
+ }
+
+ allow_rowid= table_name || (cur_table && !cur_table->next_local);
+
+ if (item->cached_table)
+ {
+ DBUG_PRINT("info", ("using cached table"));
+ /*
+ This shortcut is used by prepared statements. We assume that
+ TABLE_LIST *first_table is not changed during query execution (which
+ is true for all queries except RENAME but luckily RENAME doesn't
+ use fields...) so we can rely on reusing pointer to its member.
+ With this optimization we also miss case when addition of one more
+ field makes some prepared query ambiguous and so erroneous, but we
+ accept this trade off.
+ */
+ TABLE_LIST *table_ref= item->cached_table;
+ /*
+ The condition (table_ref->view == NULL) ensures that we will call
+ find_field_in_table even in the case of information schema tables
+ when table_ref->field_translation != NULL.
+ */
+ if (table_ref->table && !table_ref->view &&
+ (!table_ref->is_merged_derived() ||
+ (!table_ref->is_multitable() && table_ref->merged_for_insert)))
+ {
+
+ found= find_field_in_table(thd, table_ref->table, name, length,
+ TRUE, &(item->cached_field_index));
+#ifndef NO_EMBEDDED_ACCESS_CHECKS
+ /* Check if there are sufficient access rights to the found field. */
+ if (found && check_privileges &&
+ check_column_grant_in_table_ref(thd, table_ref, name, length, found))
+ found= WRONG_GRANT;
+#endif
+ }
+ else
+ found= find_field_in_table_ref(thd, table_ref, name, length, item->name.str,
+ NULL, NULL, ref, check_privileges,
+ TRUE, &(item->cached_field_index),
+ register_tree_change,
+ &actual_table);
+ if (found)
+ {
+ if (found == WRONG_GRANT)
+ return (Field*) 0;
+
+ /*
+ Only views fields should be marked as dependent, not an underlying
+ fields.
+ */
+ if (!table_ref->belong_to_view &&
+ !table_ref->belong_to_derived)
+ {
+ SELECT_LEX *current_sel= item->context->select_lex;
+ SELECT_LEX *last_select= table_ref->select_lex;
+ bool all_merged= TRUE;
+ for (SELECT_LEX *sl= current_sel; sl && sl!=last_select;
+ sl=sl->outer_select())
+ {
+ Item_in_subselect *in_subs=
+ sl->master_unit()->item->get_IN_subquery();
+ if (in_subs &&
+ in_subs->substype() == Item_subselect::IN_SUBS &&
+ in_subs->test_strategy(SUBS_SEMI_JOIN))
+ {
+ continue;
+ }
+ all_merged= FALSE;
+ break;
+ }
+ /*
+ If the field was an outer referencee, mark all selects using this
+ sub query as dependent on the outer query
+ */
+ if (!all_merged && current_sel != last_select)
+ {
+ mark_select_range_as_dependent(thd, last_select, current_sel,
+ found, *ref, item, true);
+ }
+ }
+ return found;
+ }
+ }
+ else
+ item->can_be_depended= TRUE;
+
+ if (db && lower_case_table_names)
+ {
+ /*
+ convert database to lower case for comparison.
+ We can't do this in Item_field as this would change the
+ 'name' of the item which may be used in the select list
+ */
+ strmake_buf(name_buff, db);
+ my_casedn_str(files_charset_info, name_buff);
+ db= name_buff;
+ }
+
+ if (last_table)
+ last_table= last_table->next_name_resolution_table;
+
+ for (; cur_table != last_table ;
+ cur_table= cur_table->next_name_resolution_table)
+ {
+ Field *cur_field= find_field_in_table_ref(thd, cur_table, name, length,
+ item->name.str, db, table_name, ref,
+ (thd->lex->sql_command ==
+ SQLCOM_SHOW_FIELDS)
+ ? false : check_privileges,
+ allow_rowid,
+ &(item->cached_field_index),
+ register_tree_change,
+ &actual_table);
+ if (cur_field)
+ {
+ if (cur_field == WRONG_GRANT)
+ {
+ if (thd->lex->sql_command != SQLCOM_SHOW_FIELDS)
+ return (Field*) 0;
+
+ thd->clear_error();
+ cur_field= find_field_in_table_ref(thd, cur_table, name, length,
+ item->name.str, db, table_name, ref,
+ false,
+ allow_rowid,
+ &(item->cached_field_index),
+ register_tree_change,
+ &actual_table);
+ if (cur_field)
+ {
+ Field *nf=new Field_null(NULL,0,Field::NONE,
+ &cur_field->field_name,
+ &my_charset_bin);
+ nf->init(cur_table->table);
+ cur_field= nf;
+ }
+ }
+
+ /*
+ Store the original table of the field, which may be different from
+ cur_table in the case of NATURAL/USING join.
+ */
+ item->cached_table= (!actual_table->cacheable_table || found) ?
+ 0 : actual_table;
+
+ DBUG_ASSERT(thd->where);
+ /*
+ If we found a fully qualified field we return it directly as it can't
+ have duplicates.
+ */
+ if (db)
+ return cur_field;
+
+ if (unlikely(found))
+ {
+ if (report_error == REPORT_ALL_ERRORS ||
+ report_error == IGNORE_EXCEPT_NON_UNIQUE)
+ my_error(ER_NON_UNIQ_ERROR, MYF(0),
+ table_name ? item->full_name() : name, thd->where);
+ return (Field*) 0;
+ }
+ found= cur_field;
+ }
+ }
+
+ if (likely(found))
+ return found;
+
+ /*
+ If the field was qualified and there were no tables to search, issue
+ an error that an unknown table was given. The situation is detected
+ as follows: if there were no tables we wouldn't go through the loop
+ and cur_table wouldn't be updated by the loop increment part, so it
+ will be equal to the first table.
+ */
+ if (table_name && (cur_table == first_table) &&
+ (report_error == REPORT_ALL_ERRORS ||
+ report_error == REPORT_EXCEPT_NON_UNIQUE))
+ {
+ char buff[SAFE_NAME_LEN*2 + 2];
+ if (db && db[0])
+ {
+ strxnmov(buff,sizeof(buff)-1,db,".",table_name,NullS);
+ table_name=buff;
+ }
+ my_error(ER_UNKNOWN_TABLE, MYF(0), table_name, thd->where);
+ }
+ else
+ {
+ if (report_error == REPORT_ALL_ERRORS ||
+ report_error == REPORT_EXCEPT_NON_UNIQUE)
+ my_error(ER_BAD_FIELD_ERROR, MYF(0), item->full_name(), thd->where);
+ else
+ found= not_found_field;
+ }
+ return found;
+}
+
+
+/*
+ Find Item in list of items (find_field_in_tables analog)
+
+ TODO
+ is it better return only counter?
+
+ SYNOPSIS
+ find_item_in_list()
+ find Item to find
+ items List of items
+ counter To return number of found item
+ report_error
+ REPORT_ALL_ERRORS report errors, return 0 if error
+ REPORT_EXCEPT_NOT_FOUND Do not report 'not found' error and
+ return not_found_item, report other errors,
+ return 0
+ IGNORE_ERRORS Do not report errors, return 0 if error
+ resolution Set to the resolution type if the item is found
+ (it says whether the item is resolved
+ against an alias name,
+ or as a field name without alias,
+ or as a field hidden by alias,
+ or ignoring alias)
+ limit How many items in the list to check
+ (if limit==0 then all items are to be checked)
+
+ RETURN VALUES
+ 0 Item is not found or item is not unique,
+ error message is reported
+ not_found_item Function was called with
+ report_error == REPORT_EXCEPT_NOT_FOUND and
+ item was not found. No error message was reported
+ found field
+*/
+
+/* Special Item pointer to serve as a return value from find_item_in_list(). */
+Item **not_found_item= (Item**) 0x1;
+
+
+Item **
+find_item_in_list(Item *find, List<Item> &items, uint *counter,
+ find_item_error_report_type report_error,
+ enum_resolution_type *resolution, uint limit)
+{
+ List_iterator<Item> li(items);
+ uint n_items= limit == 0 ? items.elements : limit;
+ Item **found=0, **found_unaliased= 0, *item;
+ const char *db_name=0;
+ const LEX_CSTRING *field_name= 0;
+ const char *table_name=0;
+ bool found_unaliased_non_uniq= 0;
+ /*
+ true if the item that we search for is a valid name reference
+ (and not an item that happens to have a name).
+ */
+ bool is_ref_by_name= 0;
+ uint unaliased_counter= 0;
+
+ *resolution= NOT_RESOLVED;
+
+ is_ref_by_name= (find->type() == Item::FIELD_ITEM ||
+ find->type() == Item::REF_ITEM);
+ if (is_ref_by_name)
+ {
+ field_name= &((Item_ident*) find)->field_name;
+ table_name= ((Item_ident*) find)->table_name.str;
+ db_name= ((Item_ident*) find)->db_name.str;
+ }
+
+ for (uint i= 0; i < n_items; i++)
+ {
+ item= li++;
+ if (field_name && field_name->str &&
+ (item->real_item()->type() == Item::FIELD_ITEM ||
+ ((item->type() == Item::REF_ITEM) &&
+ (((Item_ref *)item)->ref_type() == Item_ref::VIEW_REF))))
+ {
+ Item_ident *item_field= (Item_ident*) item;
+
+ /*
+ In case of group_concat() with ORDER BY condition in the QUERY
+ item_field can be field of temporary table without item name
+ (if this field created from expression argument of group_concat()),
+ => we have to check presence of name before compare
+ */
+ if (unlikely(!item_field->name.str))
+ continue;
+
+ if (table_name)
+ {
+ /*
+ If table name is specified we should find field 'field_name' in
+ table 'table_name'. According to SQL-standard we should ignore
+ aliases in this case.
+
+ Since we should NOT prefer fields from the select list over
+ other fields from the tables participating in this select in
+ case of ambiguity we have to do extra check outside this function.
+
+ We use strcmp for table names and database names as these may be
+ case sensitive. In cases where they are not case sensitive, they
+ are always in lower case.
+
+ item_field->field_name and item_field->table_name can be 0x0 if
+ item is not fix_field()'ed yet.
+ */
+ if (item_field->field_name.str && item_field->table_name.str &&
+ !lex_string_cmp(system_charset_info, &item_field->field_name,
+ field_name) &&
+ !my_strcasecmp(table_alias_charset, item_field->table_name.str,
+ table_name) &&
+ (!db_name || (item_field->db_name.str &&
+ !strcmp(item_field->db_name.str, db_name))))
+ {
+ if (found_unaliased)
+ {
+ if ((*found_unaliased)->eq(item, 0))
+ continue;
+ /*
+ Two matching fields in select list.
+ We already can bail out because we are searching through
+ unaliased names only and will have duplicate error anyway.
+ */
+ if (report_error != IGNORE_ERRORS)
+ my_error(ER_NON_UNIQ_ERROR, MYF(0),
+ find->full_name(), current_thd->where);
+ return (Item**) 0;
+ }
+ found_unaliased= li.ref();
+ unaliased_counter= i;
+ *resolution= RESOLVED_IGNORING_ALIAS;
+ if (db_name)
+ break; // Perfect match
+ }
+ }
+ else
+ {
+ bool fname_cmp= lex_string_cmp(system_charset_info,
+ &item_field->field_name,
+ field_name);
+ if (!lex_string_cmp(system_charset_info,
+ &item_field->name, field_name))
+ {
+ /*
+ If table name was not given we should scan through aliases
+ and non-aliased fields first. We are also checking unaliased
+ name of the field in then next else-if, to be able to find
+ instantly field (hidden by alias) if no suitable alias or
+ non-aliased field was found.
+ */
+ if (found)
+ {
+ if ((*found)->eq(item, 0))
+ continue; // Same field twice
+ if (report_error != IGNORE_ERRORS)
+ my_error(ER_NON_UNIQ_ERROR, MYF(0),
+ find->full_name(), current_thd->where);
+ return (Item**) 0;
+ }
+ found= li.ref();
+ *counter= i;
+ *resolution= fname_cmp ? RESOLVED_AGAINST_ALIAS:
+ RESOLVED_WITH_NO_ALIAS;
+ }
+ else if (!fname_cmp)
+ {
+ /*
+ We will use non-aliased field or react on such ambiguities only if
+ we won't be able to find aliased field.
+ Again if we have ambiguity with field outside of select list
+ we should prefer fields from select list.
+ */
+ if (found_unaliased)
+ {
+ if ((*found_unaliased)->eq(item, 0))
+ continue; // Same field twice
+ found_unaliased_non_uniq= 1;
+ }
+ found_unaliased= li.ref();
+ unaliased_counter= i;
+ }
+ }
+ }
+ else if (!table_name)
+ {
+ if (is_ref_by_name && find->name.str && item->name.str &&
+ find->name.length == item->name.length &&
+ !lex_string_cmp(system_charset_info, &item->name, &find->name))
+ {
+ found= li.ref();
+ *counter= i;
+ *resolution= RESOLVED_AGAINST_ALIAS;
+ break;
+ }
+ else if (find->eq(item,0))
+ {
+ found= li.ref();
+ *counter= i;
+ *resolution= RESOLVED_IGNORING_ALIAS;
+ break;
+ }
+ }
+ }
+
+ if (likely(found))
+ return found;
+
+ if (unlikely(found_unaliased_non_uniq))
+ {
+ if (report_error != IGNORE_ERRORS)
+ my_error(ER_NON_UNIQ_ERROR, MYF(0),
+ find->full_name(), current_thd->where);
+ return (Item **) 0;
+ }
+ if (found_unaliased)
+ {
+ found= found_unaliased;
+ *counter= unaliased_counter;
+ *resolution= RESOLVED_BEHIND_ALIAS;
+ }
+
+ if (found)
+ return found;
+
+ if (report_error != REPORT_EXCEPT_NOT_FOUND)
+ {
+ if (report_error == REPORT_ALL_ERRORS)
+ my_error(ER_BAD_FIELD_ERROR, MYF(0),
+ find->full_name(), current_thd->where);
+ return (Item **) 0;
+ }
+ else
+ return (Item **) not_found_item;
+}
+
+
+/*
+ Test if a string is a member of a list of strings.
+
+ SYNOPSIS
+ test_if_string_in_list()
+ find the string to look for
+ str_list a list of strings to be searched
+
+ DESCRIPTION
+ Sequentially search a list of strings for a string, and test whether
+ the list contains the same string.
+
+ RETURN
+ TRUE if find is in str_list
+ FALSE otherwise
+*/
+
+static bool
+test_if_string_in_list(const char *find, List<String> *str_list)
+{
+ List_iterator<String> str_list_it(*str_list);
+ String *curr_str;
+ size_t find_length= strlen(find);
+ while ((curr_str= str_list_it++))
+ {
+ if (find_length != curr_str->length())
+ continue;
+ if (!my_strcasecmp(system_charset_info, find, curr_str->ptr()))
+ return TRUE;
+ }
+ return FALSE;
+}
+
+
+/*
+ Create a new name resolution context for an item so that it is
+ being resolved in a specific table reference.
+
+ SYNOPSIS
+ set_new_item_local_context()
+ thd pointer to current thread
+ item item for which new context is created and set
+ table_ref table ref where an item showld be resolved
+
+ DESCRIPTION
+ Create a new name resolution context for an item, so that the item
+ is resolved only the supplied 'table_ref'.
+
+ RETURN
+ FALSE if all OK
+ TRUE otherwise
+*/
+
+static bool
+set_new_item_local_context(THD *thd, Item_ident *item, TABLE_LIST *table_ref)
+{
+ Name_resolution_context *context;
+ if (!(context= new (thd->mem_root) Name_resolution_context))
+ return TRUE;
+ context->init();
+ context->first_name_resolution_table=
+ context->last_name_resolution_table= table_ref;
+ item->context= context;
+ return FALSE;
+}
+
+
+/*
+ Find and mark the common columns of two table references.
+
+ SYNOPSIS
+ mark_common_columns()
+ thd [in] current thread
+ table_ref_1 [in] the first (left) join operand
+ table_ref_2 [in] the second (right) join operand
+ using_fields [in] if the join is JOIN...USING - the join columns,
+ if NATURAL join, then NULL
+ found_using_fields [out] number of fields from the USING clause that were
+ found among the common fields
+
+ DESCRIPTION
+ The procedure finds the common columns of two relations (either
+ tables or intermediate join results), and adds an equi-join condition
+ to the ON clause of 'table_ref_2' for each pair of matching columns.
+ If some of table_ref_XXX represents a base table or view, then we
+ create new 'Natural_join_column' instances for each column
+ reference and store them in the 'join_columns' of the table
+ reference.
+
+ IMPLEMENTATION
+ The procedure assumes that store_natural_using_join_columns() was
+ called for the previous level of NATURAL/USING joins.
+
+ RETURN
+ TRUE error when some common column is non-unique, or out of memory
+ FALSE OK
+*/
+
+static bool
+mark_common_columns(THD *thd, TABLE_LIST *table_ref_1, TABLE_LIST *table_ref_2,
+ List<String> *using_fields, uint *found_using_fields)
+{
+ Field_iterator_table_ref it_1, it_2;
+ Natural_join_column *nj_col_1, *nj_col_2;
+ Query_arena *arena, backup;
+ bool result= TRUE;
+ bool first_outer_loop= TRUE;
+ Field *field_1;
+ field_visibility_t field_1_invisible, field_2_invisible;
+ /*
+ Leaf table references to which new natural join columns are added
+ if the leaves are != NULL.
+ */
+ TABLE_LIST *leaf_1= (table_ref_1->nested_join &&
+ !table_ref_1->is_natural_join) ?
+ NULL : table_ref_1;
+ TABLE_LIST *leaf_2= (table_ref_2->nested_join &&
+ !table_ref_2->is_natural_join) ?
+ NULL : table_ref_2;
+
+ DBUG_ENTER("mark_common_columns");
+ DBUG_PRINT("info", ("operand_1: %s operand_2: %s",
+ table_ref_1->alias.str, table_ref_2->alias.str));
+
+ *found_using_fields= 0;
+ arena= thd->activate_stmt_arena_if_needed(&backup);
+
+ for (it_1.set(table_ref_1); !it_1.end_of_fields(); it_1.next())
+ {
+ bool found= FALSE;
+ const LEX_CSTRING *field_name_1;
+ Field *field_2= 0;
+
+ /* true if field_name_1 is a member of using_fields */
+ bool is_using_column_1;
+ if (!(nj_col_1= it_1.get_or_create_column_ref(thd, leaf_1)))
+ goto err;
+
+ field_1= nj_col_1->field();
+ field_1_invisible= field_1 ? field_1->invisible : VISIBLE;
+
+ if (field_1_invisible == INVISIBLE_FULL)
+ continue;
+
+ field_name_1= nj_col_1->name();
+ is_using_column_1= using_fields &&
+ test_if_string_in_list(field_name_1->str, using_fields);
+ DBUG_PRINT ("info", ("field_name_1=%s.%s",
+ nj_col_1->safe_table_name(),
+ field_name_1->str));
+
+ if (field_1_invisible && !is_using_column_1)
+ continue;
+
+ /*
+ Find a field with the same name in table_ref_2.
+
+ Note that for the second loop, it_2.set() will iterate over
+ table_ref_2->join_columns and not generate any new elements or
+ lists.
+ */
+ nj_col_2= NULL;
+ for (it_2.set(table_ref_2); !it_2.end_of_fields(); it_2.next())
+ {
+ Natural_join_column *cur_nj_col_2;
+ const LEX_CSTRING *cur_field_name_2;
+ if (!(cur_nj_col_2= it_2.get_or_create_column_ref(thd, leaf_2)))
+ goto err;
+
+ field_2= cur_nj_col_2->field();
+ field_2_invisible= field_2 ? field_2->invisible : VISIBLE;
+
+ if (field_2_invisible == INVISIBLE_FULL)
+ continue;
+
+ cur_field_name_2= cur_nj_col_2->name();
+ DBUG_PRINT ("info", ("cur_field_name_2=%s.%s",
+ cur_nj_col_2->safe_table_name(),
+ cur_field_name_2->str));
+
+ /*
+ Compare the two columns and check for duplicate common fields.
+ A common field is duplicate either if it was already found in
+ table_ref_2 (then found == TRUE), or if a field in table_ref_2
+ was already matched by some previous field in table_ref_1
+ (then cur_nj_col_2->is_common == TRUE).
+ Note that it is too early to check the columns outside of the
+ USING list for ambiguity because they are not actually "referenced"
+ here. These columns must be checked only on unqualified reference
+ by name (e.g. in SELECT list).
+ */
+ if (!lex_string_cmp(system_charset_info, field_name_1,
+ cur_field_name_2))
+ {
+ DBUG_PRINT ("info", ("match c1.is_common=%d", nj_col_1->is_common));
+ if (cur_nj_col_2->is_common || found)
+ {
+ my_error(ER_NON_UNIQ_ERROR, MYF(0), field_name_1->str, thd->where);
+ goto err;
+ }
+ if ((!using_fields && !field_2_invisible) || is_using_column_1)
+ {
+ DBUG_ASSERT(nj_col_2 == NULL);
+ nj_col_2= cur_nj_col_2;
+ found= TRUE;
+ }
+ }
+ }
+ if (first_outer_loop && leaf_2)
+ {
+ /*
+ Make sure that the next inner loop "knows" that all columns
+ are materialized already.
+ */
+ leaf_2->is_join_columns_complete= TRUE;
+ first_outer_loop= FALSE;
+ }
+ if (!found)
+ continue; // No matching field
+
+ /*
+ field_1 and field_2 have the same names. Check if they are in the USING
+ clause (if present), mark them as common fields, and add a new
+ equi-join condition to the ON clause.
+ */
+ if (nj_col_2)
+ {
+ /*
+ Create non-fixed fully qualified field and let fix_fields to
+ resolve it.
+ */
+ Item *item_1= nj_col_1->create_item(thd);
+ Item *item_2= nj_col_2->create_item(thd);
+ Item_ident *item_ident_1, *item_ident_2;
+ Item_func_eq *eq_cond;
+
+ if (!item_1 || !item_2)
+ goto err; // out of memory
+
+ /*
+ The following assert checks that the two created items are of
+ type Item_ident.
+ */
+ DBUG_ASSERT(!thd->lex->current_select->no_wrap_view_item);
+ /*
+ In the case of no_wrap_view_item == 0, the created items must be
+ of sub-classes of Item_ident.
+ */
+ DBUG_ASSERT(item_1->type() == Item::FIELD_ITEM ||
+ item_1->type() == Item::REF_ITEM);
+ DBUG_ASSERT(item_2->type() == Item::FIELD_ITEM ||
+ item_2->type() == Item::REF_ITEM);
+
+ /*
+ We need to cast item_1,2 to Item_ident, because we need to hook name
+ resolution contexts specific to each item.
+ */
+ item_ident_1= (Item_ident*) item_1;
+ item_ident_2= (Item_ident*) item_2;
+ /*
+ Create and hook special name resolution contexts to each item in the
+ new join condition . We need this to both speed-up subsequent name
+ resolution of these items, and to enable proper name resolution of
+ the items during the execute phase of PS.
+ */
+ if (set_new_item_local_context(thd, item_ident_1, nj_col_1->table_ref) ||
+ set_new_item_local_context(thd, item_ident_2, nj_col_2->table_ref))
+ goto err;
+
+ if (!(eq_cond= new (thd->mem_root) Item_func_eq(thd, item_ident_1, item_ident_2)))
+ goto err; /* Out of memory. */
+
+ /*
+ Add the new equi-join condition to the ON clause. Notice that
+ fix_fields() is applied to all ON conditions in setup_conds()
+ so we don't do it here.
+ */
+ add_join_on(thd, (table_ref_1->outer_join & JOIN_TYPE_RIGHT ?
+ table_ref_1 : table_ref_2),
+ eq_cond);
+
+ nj_col_1->is_common= nj_col_2->is_common= TRUE;
+ DBUG_PRINT ("info", ("%s.%s and %s.%s are common",
+ nj_col_1->safe_table_name(),
+ nj_col_1->name()->str,
+ nj_col_2->safe_table_name(),
+ nj_col_2->name()->str));
+
+ if (field_1)
+ update_field_dependencies(thd, field_1, field_1->table);
+ if (field_2)
+ update_field_dependencies(thd, field_2, field_2->table);
+
+ if (using_fields != NULL)
+ ++(*found_using_fields);
+ }
+ }
+ if (leaf_1)
+ leaf_1->is_join_columns_complete= TRUE;
+
+ /*
+ Everything is OK.
+ Notice that at this point there may be some column names in the USING
+ clause that are not among the common columns. This is an SQL error and
+ we check for this error in store_natural_using_join_columns() when
+ (found_using_fields < length(join_using_fields)).
+ */
+ result= FALSE;
+
+err:
+ if (arena)
+ thd->restore_active_arena(arena, &backup);
+ DBUG_RETURN(result);
+}
+
+
+
+/*
+ Materialize and store the row type of NATURAL/USING join.
+
+ SYNOPSIS
+ store_natural_using_join_columns()
+ thd current thread
+ natural_using_join the table reference of the NATURAL/USING join
+ table_ref_1 the first (left) operand (of a NATURAL/USING join).
+ table_ref_2 the second (right) operand (of a NATURAL/USING join).
+ using_fields if the join is JOIN...USING - the join columns,
+ if NATURAL join, then NULL
+ found_using_fields number of fields from the USING clause that were
+ found among the common fields
+
+ DESCRIPTION
+ Iterate over the columns of both join operands and sort and store
+ all columns into the 'join_columns' list of natural_using_join
+ where the list is formed by three parts:
+ part1: The coalesced columns of table_ref_1 and table_ref_2,
+ sorted according to the column order of the first table.
+ part2: The other columns of the first table, in the order in
+ which they were defined in CREATE TABLE.
+ part3: The other columns of the second table, in the order in
+ which they were defined in CREATE TABLE.
+ Time complexity - O(N1+N2), where Ni = length(table_ref_i).
+
+ IMPLEMENTATION
+ The procedure assumes that mark_common_columns() has been called
+ for the join that is being processed.
+
+ RETURN
+ TRUE error: Some common column is ambiguous
+ FALSE OK
+*/
+
+static bool
+store_natural_using_join_columns(THD *thd, TABLE_LIST *natural_using_join,
+ TABLE_LIST *table_ref_1,
+ TABLE_LIST *table_ref_2,
+ List<String> *using_fields,
+ uint found_using_fields)
+{
+ Field_iterator_table_ref it_1, it_2;
+ Natural_join_column *nj_col_1, *nj_col_2;
+ Query_arena *arena, backup;
+ bool result= TRUE;
+ List<Natural_join_column> *non_join_columns;
+ List<Natural_join_column> *join_columns;
+ DBUG_ENTER("store_natural_using_join_columns");
+
+ DBUG_ASSERT(!natural_using_join->join_columns);
+
+ arena= thd->activate_stmt_arena_if_needed(&backup);
+
+ if (!(non_join_columns= new List<Natural_join_column>) ||
+ !(join_columns= new List<Natural_join_column>))
+ goto err;
+
+ /* Append the columns of the first join operand. */
+ for (it_1.set(table_ref_1); !it_1.end_of_fields(); it_1.next())
+ {
+ nj_col_1= it_1.get_natural_column_ref();
+ if (nj_col_1->is_common)
+ {
+ join_columns->push_back(nj_col_1, thd->mem_root);
+ /* Reset the common columns for the next call to mark_common_columns. */
+ nj_col_1->is_common= FALSE;
+ }
+ else
+ non_join_columns->push_back(nj_col_1, thd->mem_root);
+ }
+
+ /*
+ Check that all columns in the USING clause are among the common
+ columns. If this is not the case, report the first one that was
+ not found in an error.
+ */
+ if (using_fields && found_using_fields < using_fields->elements)
+ {
+ String *using_field_name;
+ List_iterator_fast<String> using_fields_it(*using_fields);
+ while ((using_field_name= using_fields_it++))
+ {
+ const char *using_field_name_ptr= using_field_name->c_ptr();
+ List_iterator_fast<Natural_join_column>
+ it(*join_columns);
+ Natural_join_column *common_field;
+
+ for (;;)
+ {
+ /* If reached the end of fields, and none was found, report error. */
+ if (!(common_field= it++))
+ {
+ my_error(ER_BAD_FIELD_ERROR, MYF(0), using_field_name_ptr,
+ current_thd->where);
+ goto err;
+ }
+ if (!my_strcasecmp(system_charset_info,
+ common_field->name()->str, using_field_name_ptr))
+ break; // Found match
+ }
+ }
+ }
+
+ /* Append the non-equi-join columns of the second join operand. */
+ for (it_2.set(table_ref_2); !it_2.end_of_fields(); it_2.next())
+ {
+ nj_col_2= it_2.get_natural_column_ref();
+ if (!nj_col_2->is_common)
+ non_join_columns->push_back(nj_col_2, thd->mem_root);
+ else
+ {
+ /* Reset the common columns for the next call to mark_common_columns. */
+ nj_col_2->is_common= FALSE;
+ }
+ }
+
+ if (non_join_columns->elements > 0)
+ join_columns->append(non_join_columns);
+ natural_using_join->join_columns= join_columns;
+ natural_using_join->is_join_columns_complete= TRUE;
+
+ result= FALSE;
+
+ if (arena)
+ thd->restore_active_arena(arena, &backup);
+ DBUG_RETURN(result);
+
+err:
+ /*
+ Actually we failed to build join columns list, so we have to
+ clear it to avoid problems with half-build join on next run.
+ The list was created in mark_common_columns().
+ */
+ table_ref_1->remove_join_columns();
+ table_ref_2->remove_join_columns();
+
+ if (arena)
+ thd->restore_active_arena(arena, &backup);
+ DBUG_RETURN(TRUE);
+}
+
+
+/*
+ Precompute and store the row types of the top-most NATURAL/USING joins.
+
+ SYNOPSIS
+ store_top_level_join_columns()
+ thd current thread
+ table_ref nested join or table in a FROM clause
+ left_neighbor neighbor table reference to the left of table_ref at the
+ same level in the join tree
+ right_neighbor neighbor table reference to the right of table_ref at the
+ same level in the join tree
+
+ DESCRIPTION
+ The procedure performs a post-order traversal of a nested join tree
+ and materializes the row types of NATURAL/USING joins in a
+ bottom-up manner until it reaches the TABLE_LIST elements that
+ represent the top-most NATURAL/USING joins. The procedure should be
+ applied to each element of SELECT_LEX::top_join_list (i.e. to each
+ top-level element of the FROM clause).
+
+ IMPLEMENTATION
+ Notice that the table references in the list nested_join->join_list
+ are in reverse order, thus when we iterate over it, we are moving
+ from the right to the left in the FROM clause.
+
+ RETURN
+ TRUE Error
+ FALSE OK
+*/
+
+static bool
+store_top_level_join_columns(THD *thd, TABLE_LIST *table_ref,
+ TABLE_LIST *left_neighbor,
+ TABLE_LIST *right_neighbor)
+{
+ Query_arena *arena, backup;
+ bool result= TRUE;
+
+ DBUG_ENTER("store_top_level_join_columns");
+
+ arena= thd->activate_stmt_arena_if_needed(&backup);
+
+ /* Call the procedure recursively for each nested table reference. */
+ if (table_ref->nested_join)
+ {
+ List_iterator_fast<TABLE_LIST> nested_it(table_ref->nested_join->join_list);
+ TABLE_LIST *same_level_left_neighbor= nested_it++;
+ TABLE_LIST *same_level_right_neighbor= NULL;
+ /* Left/right-most neighbors, possibly at higher levels in the join tree. */
+ TABLE_LIST *real_left_neighbor, *real_right_neighbor;
+
+ while (same_level_left_neighbor)
+ {
+ TABLE_LIST *cur_table_ref= same_level_left_neighbor;
+ same_level_left_neighbor= nested_it++;
+ /*
+ The order of RIGHT JOIN operands is reversed in 'join list' to
+ transform it into a LEFT JOIN. However, in this procedure we need
+ the join operands in their lexical order, so below we reverse the
+ join operands. Notice that this happens only in the first loop,
+ and not in the second one, as in the second loop
+ same_level_left_neighbor == NULL.
+ This is the correct behavior, because the second loop sets
+ cur_table_ref reference correctly after the join operands are
+ swapped in the first loop.
+ */
+ if (same_level_left_neighbor &&
+ cur_table_ref->outer_join & JOIN_TYPE_RIGHT)
+ {
+ /* This can happen only for JOIN ... ON. */
+ DBUG_ASSERT(table_ref->nested_join->join_list.elements == 2);
+ swap_variables(TABLE_LIST*, same_level_left_neighbor, cur_table_ref);
+ }
+
+ /*
+ Pick the parent's left and right neighbors if there are no immediate
+ neighbors at the same level.
+ */
+ real_left_neighbor= (same_level_left_neighbor) ?
+ same_level_left_neighbor : left_neighbor;
+ real_right_neighbor= (same_level_right_neighbor) ?
+ same_level_right_neighbor : right_neighbor;
+
+ if (cur_table_ref->nested_join &&
+ store_top_level_join_columns(thd, cur_table_ref,
+ real_left_neighbor, real_right_neighbor))
+ goto err;
+ same_level_right_neighbor= cur_table_ref;
+ }
+ }
+
+ /*
+ If this is a NATURAL/USING join, materialize its result columns and
+ convert to a JOIN ... ON.
+ */
+ if (table_ref->is_natural_join)
+ {
+ DBUG_ASSERT(table_ref->nested_join &&
+ table_ref->nested_join->join_list.elements == 2);
+ List_iterator_fast<TABLE_LIST> operand_it(table_ref->nested_join->join_list);
+ /*
+ Notice that the order of join operands depends on whether table_ref
+ represents a LEFT or a RIGHT join. In a RIGHT join, the operands are
+ in inverted order.
+ */
+ TABLE_LIST *table_ref_2= operand_it++; /* Second NATURAL join operand.*/
+ TABLE_LIST *table_ref_1= operand_it++; /* First NATURAL join operand. */
+ List<String> *using_fields= table_ref->join_using_fields;
+ uint found_using_fields;
+
+ /*
+ The two join operands were interchanged in the parser, change the order
+ back for 'mark_common_columns'.
+ */
+ if (table_ref_2->outer_join & JOIN_TYPE_RIGHT)
+ swap_variables(TABLE_LIST*, table_ref_1, table_ref_2);
+ if (mark_common_columns(thd, table_ref_1, table_ref_2,
+ using_fields, &found_using_fields))
+ goto err;
+
+ /*
+ Swap the join operands back, so that we pick the columns of the second
+ one as the coalesced columns. In this way the coalesced columns are the
+ same as of an equivalent LEFT JOIN.
+ */
+ if (table_ref_1->outer_join & JOIN_TYPE_RIGHT)
+ swap_variables(TABLE_LIST*, table_ref_1, table_ref_2);
+ if (store_natural_using_join_columns(thd, table_ref, table_ref_1,
+ table_ref_2, using_fields,
+ found_using_fields))
+ goto err;
+
+ /*
+ Change NATURAL JOIN to JOIN ... ON. We do this for both operands
+ because either one of them or the other is the one with the
+ natural join flag because RIGHT joins are transformed into LEFT,
+ and the two tables may be reordered.
+ */
+ table_ref_1->natural_join= table_ref_2->natural_join= NULL;
+
+ /* Add a TRUE condition to outer joins that have no common columns. */
+ if (table_ref_2->outer_join &&
+ !table_ref_1->on_expr && !table_ref_2->on_expr)
+ table_ref_2->on_expr= new (thd->mem_root) Item_int(thd, (longlong) 1, 1); // Always true.
+
+ /* Change this table reference to become a leaf for name resolution. */
+ if (left_neighbor)
+ {
+ TABLE_LIST *last_leaf_on_the_left;
+ last_leaf_on_the_left= left_neighbor->last_leaf_for_name_resolution();
+ last_leaf_on_the_left->next_name_resolution_table= table_ref;
+ }
+ if (right_neighbor)
+ {
+ TABLE_LIST *first_leaf_on_the_right;
+ first_leaf_on_the_right= right_neighbor->first_leaf_for_name_resolution();
+ table_ref->next_name_resolution_table= first_leaf_on_the_right;
+ }
+ else
+ table_ref->next_name_resolution_table= NULL;
+ }
+ result= FALSE; /* All is OK. */
+
+err:
+ if (arena)
+ thd->restore_active_arena(arena, &backup);
+ DBUG_RETURN(result);
+}
+
+
+/*
+ Compute and store the row types of the top-most NATURAL/USING joins
+ in a FROM clause.
+
+ SYNOPSIS
+ setup_natural_join_row_types()
+ thd current thread
+ from_clause list of top-level table references in a FROM clause
+
+ DESCRIPTION
+ Apply the procedure 'store_top_level_join_columns' to each of the
+ top-level table referencs of the FROM clause. Adjust the list of tables
+ for name resolution - context->first_name_resolution_table to the
+ top-most, lef-most NATURAL/USING join.
+
+ IMPLEMENTATION
+ Notice that the table references in 'from_clause' are in reverse
+ order, thus when we iterate over it, we are moving from the right
+ to the left in the FROM clause.
+
+ NOTES
+ We can't run this many times as the first_name_resolution_table would
+ be different for subsequent runs when sub queries has been optimized
+ away.
+
+ RETURN
+ TRUE Error
+ FALSE OK
+*/
+
+static bool setup_natural_join_row_types(THD *thd,
+ List<TABLE_LIST> *from_clause,
+ Name_resolution_context *context)
+{
+ DBUG_ENTER("setup_natural_join_row_types");
+ thd->where= "from clause";
+ if (from_clause->elements == 0)
+ DBUG_RETURN(false); /* We come here in the case of UNIONs. */
+
+ /*
+ Do not redo work if already done:
+ 1) for stored procedures,
+ 2) for multitable update after lock failure and table reopening.
+ */
+ if (!context->select_lex->first_natural_join_processing)
+ {
+ context->first_name_resolution_table= context->natural_join_first_table;
+ DBUG_PRINT("info", ("using cached setup_natural_join_row_types"));
+ DBUG_RETURN(false);
+ }
+
+ List_iterator_fast<TABLE_LIST> table_ref_it(*from_clause);
+ TABLE_LIST *table_ref; /* Current table reference. */
+ /* Table reference to the left of the current. */
+ TABLE_LIST *left_neighbor;
+ /* Table reference to the right of the current. */
+ TABLE_LIST *right_neighbor= NULL;
+
+ /* Note that tables in the list are in reversed order */
+ for (left_neighbor= table_ref_it++; left_neighbor ; )
+ {
+ table_ref= left_neighbor;
+ do
+ {
+ left_neighbor= table_ref_it++;
+ }
+ while (left_neighbor && left_neighbor->sj_subq_pred);
+
+ if (store_top_level_join_columns(thd, table_ref,
+ left_neighbor, right_neighbor))
+ DBUG_RETURN(true);
+ if (left_neighbor)
+ {
+ TABLE_LIST *first_leaf_on_the_right;
+ first_leaf_on_the_right= table_ref->first_leaf_for_name_resolution();
+ left_neighbor->next_name_resolution_table= first_leaf_on_the_right;
+ }
+ right_neighbor= table_ref;
+ }
+
+ /*
+ Store the top-most, left-most NATURAL/USING join, so that we start
+ the search from that one instead of context->table_list. At this point
+ right_neighbor points to the left-most top-level table reference in the
+ FROM clause.
+ */
+ DBUG_ASSERT(right_neighbor);
+ context->first_name_resolution_table=
+ right_neighbor->first_leaf_for_name_resolution();
+ /*
+ This is only to ensure that first_name_resolution_table doesn't
+ change on re-execution
+ */
+ context->natural_join_first_table= context->first_name_resolution_table;
+ context->select_lex->first_natural_join_processing= false;
+ DBUG_RETURN (false);
+}
+
+
+/****************************************************************************
+** Expand all '*' in given fields
+****************************************************************************/
+
+int setup_wild(THD *thd, TABLE_LIST *tables, List<Item> &fields,
+ List<Item> *sum_func_list, SELECT_LEX *select_lex, bool returning_field)
+{
+ Item *item;
+ List_iterator<Item> it(fields);
+ Query_arena *arena, backup;
+ DBUG_ENTER("setup_wild");
+
+ if (!select_lex->with_wild)
+ DBUG_RETURN(0);
+
+ /*
+ Don't use arena if we are not in prepared statements or stored procedures
+ For PS/SP we have to use arena to remember the changes
+ */
+ arena= thd->activate_stmt_arena_if_needed(&backup);
+
+ thd->lex->current_select->cur_pos_in_select_list= 0;
+ while (select_lex->with_wild && (item= it++))
+ {
+ if (item->type() == Item::FIELD_ITEM &&
+ ((Item_field*) item)->field_name.str == star_clex_str.str &&
+ !((Item_field*) item)->field)
+ {
+ uint elem= fields.elements;
+ bool any_privileges= ((Item_field *) item)->any_privileges;
+ Item_subselect *subsel= thd->lex->current_select->master_unit()->item;
+ if (subsel &&
+ subsel->substype() == Item_subselect::EXISTS_SUBS)
+ {
+ /*
+ It is EXISTS(SELECT * ...) and we can replace * by any constant.
+
+ Item_int do not need fix_fields() because it is basic constant.
+ */
+ it.replace(new (thd->mem_root) Item_int(thd, "Not_used", (longlong) 1,
+ MY_INT64_NUM_DECIMAL_DIGITS));
+ }
+ else if (insert_fields(thd, ((Item_field*) item)->context,
+ ((Item_field*) item)->db_name.str,
+ ((Item_field*) item)->table_name.str, &it,
+ any_privileges, &select_lex->hidden_bit_fields, returning_field))
+ {
+ if (arena)
+ thd->restore_active_arena(arena, &backup);
+ DBUG_RETURN(-1);
+ }
+ if (sum_func_list)
+ {
+ /*
+ sum_func_list is a list that has the fields list as a tail.
+ Because of this we have to update the element count also for this
+ list after expanding the '*' entry.
+ */
+ sum_func_list->elements+= fields.elements - elem;
+ }
+ select_lex->with_wild--;
+ }
+ else
+ thd->lex->current_select->cur_pos_in_select_list++;
+ }
+ DBUG_ASSERT(!select_lex->with_wild);
+ thd->lex->current_select->cur_pos_in_select_list= UNDEF_POS;
+ if (arena)
+ thd->restore_active_arena(arena, &backup);
+ DBUG_RETURN(0);
+}
+
+/****************************************************************************
+** Check that all given fields exists and fill struct with current data
+****************************************************************************/
+
+bool setup_fields(THD *thd, Ref_ptr_array ref_pointer_array,
+ List<Item> &fields, enum_column_usage column_usage,
+ List<Item> *sum_func_list, List<Item> *pre_fix,
+ bool allow_sum_func)
+{
+ Item *item;
+ enum_column_usage saved_column_usage= thd->column_usage;
+ nesting_map save_allow_sum_func= thd->lex->allow_sum_func;
+ List_iterator<Item> it(fields);
+ bool save_is_item_list_lookup;
+ bool make_pre_fix= (pre_fix && (pre_fix->elements == 0));
+ DBUG_ENTER("setup_fields");
+ DBUG_PRINT("enter", ("ref_pointer_array: %p", ref_pointer_array.array()));
+
+ thd->column_usage= column_usage;
+ DBUG_PRINT("info", ("thd->column_usage: %d", thd->column_usage));
+ if (allow_sum_func)
+ thd->lex->allow_sum_func.set_bit(thd->lex->current_select->nest_level);
+ thd->where= THD::DEFAULT_WHERE;
+ save_is_item_list_lookup= thd->lex->current_select->is_item_list_lookup;
+ thd->lex->current_select->is_item_list_lookup= 0;
+
+ /*
+ To prevent fail on forward lookup we fill it with zeroes,
+ then if we got pointer on zero after find_item_in_list we will know
+ that it is forward lookup.
+
+ There is other way to solve problem: fill array with pointers to list,
+ but it will be slower.
+
+ TODO: remove it when (if) we made one list for allfields and
+ ref_pointer_array
+ */
+ if (!ref_pointer_array.is_null())
+ {
+ DBUG_ASSERT(ref_pointer_array.size() >= fields.elements);
+ memset(ref_pointer_array.array(), 0, sizeof(Item *) * fields.elements);
+ }
+
+ /*
+ We call set_entry() there (before fix_fields() of the whole list of field
+ items) because:
+ 1) the list of field items has same order as in the query, and the
+ Item_func_get_user_var item may go before the Item_func_set_user_var:
+ SELECT @a, @a := 10 FROM t;
+ 2) The entry->update_query_id value controls constantness of
+ Item_func_get_user_var items, so in presence of Item_func_set_user_var
+ items we have to refresh their entries before fixing of
+ Item_func_get_user_var items.
+ */
+ List_iterator<Item_func_set_user_var> li(thd->lex->set_var_list);
+ Item_func_set_user_var *var;
+ while ((var= li++))
+ var->set_entry(thd, FALSE);
+
+ Ref_ptr_array ref= ref_pointer_array;
+ thd->lex->current_select->cur_pos_in_select_list= 0;
+ while ((item= it++))
+ {
+ if (make_pre_fix)
+ pre_fix->push_back(item, thd->stmt_arena->mem_root);
+
+ if (item->fix_fields_if_needed_for_scalar(thd, it.ref()))
+ {
+ thd->lex->current_select->is_item_list_lookup= save_is_item_list_lookup;
+ thd->lex->allow_sum_func= save_allow_sum_func;
+ thd->column_usage= saved_column_usage;
+ DBUG_PRINT("info", ("thd->column_usage: %d", thd->column_usage));
+ DBUG_RETURN(TRUE); /* purecov: inspected */
+ }
+ item= *(it.ref()); // Item might have changed in fix_fields()
+ if (!ref.is_null())
+ {
+ ref[0]= item;
+ ref.pop_front();
+ }
+ /*
+ split_sum_func() must be called for Window Function items, see
+ Item_window_func::split_sum_func.
+ */
+ if (sum_func_list &&
+ ((item->with_sum_func() && item->type() != Item::SUM_FUNC_ITEM) ||
+ item->with_window_func))
+ {
+ item->split_sum_func(thd, ref_pointer_array, *sum_func_list,
+ SPLIT_SUM_SELECT);
+ }
+ thd->lex->current_select->select_list_tables|= item->used_tables();
+ thd->lex->used_tables|= item->used_tables();
+ thd->lex->current_select->cur_pos_in_select_list++;
+ }
+ thd->lex->current_select->is_item_list_lookup= save_is_item_list_lookup;
+ thd->lex->current_select->cur_pos_in_select_list= UNDEF_POS;
+
+ thd->lex->allow_sum_func= save_allow_sum_func;
+ thd->column_usage= saved_column_usage;
+ DBUG_PRINT("info", ("thd->column_usage: %d", thd->column_usage));
+ DBUG_RETURN(MY_TEST(thd->is_error()));
+}
+
+
+/*
+ Perform checks like all given fields exists, if exists fill struct with
+ current data and expand all '*' in given fields for LEX::returning.
+
+ SYNOPSIS
+ thd Thread handler
+ table_list Global/local table list
+*/
+
+int setup_returning_fields(THD* thd, TABLE_LIST* table_list)
+{
+ if (!thd->lex->has_returning())
+ return 0;
+ return setup_wild(thd, table_list, thd->lex->returning()->item_list, NULL,
+ thd->lex->returning(), true)
+ || setup_fields(thd, Ref_ptr_array(), thd->lex->returning()->item_list,
+ MARK_COLUMNS_READ, NULL, NULL, false);
+}
+
+
+/*
+ make list of leaves of join table tree
+
+ SYNOPSIS
+ make_leaves_list()
+ list pointer to pointer on list first element
+ tables table list
+ full_table_list whether to include tables from mergeable derived table/view.
+ we need them for checks for INSERT/UPDATE statements only.
+
+ RETURN pointer on pointer to next_leaf of last element
+*/
+
+void make_leaves_list(THD *thd, List<TABLE_LIST> &list, TABLE_LIST *tables,
+ bool full_table_list, TABLE_LIST *boundary)
+
+{
+ for (TABLE_LIST *table= tables; table; table= table->next_local)
+ {
+ if (table == boundary)
+ full_table_list= !full_table_list;
+ if (full_table_list && table->is_merged_derived())
+ {
+ SELECT_LEX *select_lex= table->get_single_select();
+ /*
+ It's safe to use select_lex->leaf_tables because all derived
+ tables/views were already prepared and has their leaf_tables
+ set properly.
+ */
+ make_leaves_list(thd, list, select_lex->get_table_list(),
+ full_table_list, boundary);
+ }
+ else
+ {
+ list.push_back(table, thd->mem_root);
+ }
+ }
+}
+
+/*
+ prepare tables
+
+ SYNOPSIS
+ setup_tables()
+ thd Thread handler
+ context name resolution contest to setup table list there
+ from_clause Top-level list of table references in the FROM clause
+ tables Table list (select_lex->table_list)
+ leaves List of join table leaves list (select_lex->leaf_tables)
+ refresh It is only refresh for subquery
+ select_insert It is SELECT ... INSERT command
+ full_table_list a parameter to pass to the make_leaves_list function
+
+ NOTE
+ Check also that the 'used keys' and 'ignored keys' exists and set up the
+ table structure accordingly.
+ Create a list of leaf tables. For queries with NATURAL/USING JOINs,
+ compute the row types of the top most natural/using join table references
+ and link these into a list of table references for name resolution.
+
+ This has to be called for all tables that are used by items, as otherwise
+ table->map is not set and all Item_field will be regarded as const items.
+
+ RETURN
+ FALSE ok; In this case *map will includes the chosen index
+ TRUE error
+*/
+
+bool setup_tables(THD *thd, Name_resolution_context *context,
+ List<TABLE_LIST> *from_clause, TABLE_LIST *tables,
+ List<TABLE_LIST> &leaves, bool select_insert,
+ bool full_table_list)
+{
+ uint tablenr= 0;
+ List_iterator<TABLE_LIST> ti(leaves);
+ TABLE_LIST *table_list;
+
+ DBUG_ENTER("setup_tables");
+
+ DBUG_ASSERT ((select_insert && !tables->next_name_resolution_table) || !tables ||
+ (context->table_list && context->first_name_resolution_table));
+ /*
+ this is used for INSERT ... SELECT.
+ For select we setup tables except first (and its underlying tables)
+ */
+ TABLE_LIST *first_select_table= (select_insert ?
+ tables->next_local:
+ 0);
+ SELECT_LEX *select_lex= select_insert ? thd->lex->first_select_lex() :
+ thd->lex->current_select;
+ if (select_lex->first_cond_optimization)
+ {
+ leaves.empty();
+ if (select_lex->prep_leaf_list_state != SELECT_LEX::SAVED)
+ {
+ make_leaves_list(thd, leaves, tables, full_table_list, first_select_table);
+ select_lex->prep_leaf_list_state= SELECT_LEX::READY;
+ select_lex->leaf_tables_exec.empty();
+ }
+ else
+ {
+ List_iterator_fast <TABLE_LIST> ti(select_lex->leaf_tables_prep);
+ while ((table_list= ti++))
+ leaves.push_back(table_list, thd->mem_root);
+ }
+
+ while ((table_list= ti++))
+ {
+ TABLE *table= table_list->table;
+ if (table)
+ table->pos_in_table_list= table_list;
+ if (first_select_table &&
+ table_list->top_table() == first_select_table)
+ {
+ /* new counting for SELECT of INSERT ... SELECT command */
+ first_select_table= 0;
+ thd->lex->first_select_lex()->insert_tables= tablenr;
+ tablenr= 0;
+ }
+ if(table_list->jtbm_subselect)
+ {
+ table_list->jtbm_table_no= tablenr;
+ }
+ else if (table)
+ {
+ table->pos_in_table_list= table_list;
+ setup_table_map(table, table_list, tablenr);
+
+ if (table_list->process_index_hints(table))
+ DBUG_RETURN(1);
+ }
+ tablenr++;
+ /*
+ We test the max tables here as we setup_table_map() should not be called
+ with tablenr >= 64
+ */
+ if (tablenr > MAX_TABLES)
+ {
+ my_error(ER_TOO_MANY_TABLES,MYF(0), static_cast<int>(MAX_TABLES));
+ DBUG_RETURN(1);
+ }
+ }
+ }
+ else
+ {
+ List_iterator_fast <TABLE_LIST> ti(select_lex->leaf_tables_exec);
+ select_lex->leaf_tables.empty();
+ while ((table_list= ti++))
+ {
+ if(table_list->jtbm_subselect)
+ {
+ table_list->jtbm_table_no= table_list->tablenr_exec;
+ }
+ else
+ {
+ table_list->table->tablenr= table_list->tablenr_exec;
+ table_list->table->map= table_list->map_exec;
+ table_list->table->maybe_null= table_list->maybe_null_exec;
+ table_list->table->pos_in_table_list= table_list;
+ if (table_list->process_index_hints(table_list->table))
+ DBUG_RETURN(1);
+ }
+ select_lex->leaf_tables.push_back(table_list);
+ }
+ }
+
+ for (table_list= tables;
+ table_list;
+ table_list= table_list->next_local)
+ {
+ if (table_list->merge_underlying_list)
+ {
+ DBUG_ASSERT(table_list->is_merged_derived());
+ Query_arena *arena, backup;
+ arena= thd->activate_stmt_arena_if_needed(&backup);
+ bool res;
+ res= table_list->setup_underlying(thd);
+ if (arena)
+ thd->restore_active_arena(arena, &backup);
+ if (res)
+ DBUG_RETURN(1);
+ }
+
+ if (table_list->jtbm_subselect)
+ {
+ Item *item= table_list->jtbm_subselect->optimizer;
+ if (!table_list->jtbm_subselect->optimizer->fixed &&
+ table_list->jtbm_subselect->optimizer->fix_fields(thd, &item))
+ {
+ my_error(ER_TOO_MANY_TABLES,MYF(0), static_cast<int>(MAX_TABLES)); /* psergey-todo: WHY ER_TOO_MANY_TABLES ???*/
+ DBUG_RETURN(1);
+ }
+ DBUG_ASSERT(item == table_list->jtbm_subselect->optimizer);
+ }
+ }
+
+ /* Precompute and store the row types of NATURAL/USING joins. */
+ if (setup_natural_join_row_types(thd, from_clause, context))
+ DBUG_RETURN(1);
+
+ DBUG_RETURN(0);
+}
+
+
+/*
+ prepare tables and check access for the view tables
+
+ SYNOPSIS
+ setup_tables_and_check_access()
+ thd Thread handler
+ context name resolution contest to setup table list there
+ from_clause Top-level list of table references in the FROM clause
+ tables Table list (select_lex->table_list)
+ conds Condition of current SELECT (can be changed by VIEW)
+ leaves List of join table leaves list (select_lex->leaf_tables)
+ refresh It is onle refresh for subquery
+ select_insert It is SELECT ... INSERT command
+ want_access what access is needed
+ full_table_list a parameter to pass to the make_leaves_list function
+
+ NOTE
+ a wrapper for check_tables that will also check the resulting
+ table leaves list for access to all the tables that belong to a view
+
+ RETURN
+ FALSE ok; In this case *map will include the chosen index
+ TRUE error
+*/
+bool setup_tables_and_check_access(THD *thd, Name_resolution_context *context,
+ List<TABLE_LIST> *from_clause,
+ TABLE_LIST *tables,
+ List<TABLE_LIST> &leaves,
+ bool select_insert,
+ privilege_t want_access_first,
+ privilege_t want_access,
+ bool full_table_list)
+{
+ DBUG_ENTER("setup_tables_and_check_access");
+
+ if (setup_tables(thd, context, from_clause, tables,
+ leaves, select_insert, full_table_list))
+ DBUG_RETURN(TRUE);
+
+ List_iterator<TABLE_LIST> ti(leaves);
+ TABLE_LIST *table_list;
+ privilege_t access= want_access_first;
+ while ((table_list= ti++))
+ {
+ if (table_list->belong_to_view && !table_list->view &&
+ check_single_table_access(thd, access, table_list, FALSE))
+ {
+ tables->hide_view_error(thd);
+ DBUG_RETURN(TRUE);
+ }
+ access= want_access;
+ }
+ DBUG_RETURN(FALSE);
+}
+
+
+/*
+ Create a key_map from a list of index names
+
+ SYNOPSIS
+ get_key_map_from_key_list()
+ map key_map to fill in
+ table Table
+ index_list List of index names
+
+ RETURN
+ 0 ok; In this case *map will includes the choosed index
+ 1 error
+*/
+
+bool get_key_map_from_key_list(key_map *map, TABLE *table,
+ List<String> *index_list)
+{
+ List_iterator_fast<String> it(*index_list);
+ String *name;
+ uint pos;
+
+ map->clear_all();
+ while ((name=it++))
+ {
+ if (table->s->keynames.type_names == 0 ||
+ (pos= find_type(&table->s->keynames, name->ptr(),
+ name->length(), 1)) <=
+ 0)
+ {
+ my_error(ER_KEY_DOES_NOT_EXISTS, MYF(0), name->c_ptr(),
+ table->pos_in_table_list->alias.str);
+ map->set_all();
+ return 1;
+ }
+ map->set_bit(pos-1);
+ }
+ return 0;
+}
+
+
+/*
+ Drops in all fields instead of current '*' field
+
+ SYNOPSIS
+ insert_fields()
+ thd Thread handler
+ context Context for name resolution
+ db_name Database name in case of 'database_name.table_name.*'
+ table_name Table name in case of 'table_name.*'
+ it Pointer to '*'
+ any_privileges 0 If we should ensure that we have SELECT privileges
+ for all columns
+ 1 If any privilege is ok
+ RETURN
+ 0 ok 'it' is updated to point at last inserted
+ 1 error. Error message is generated but not sent to client
+*/
+
+bool
+insert_fields(THD *thd, Name_resolution_context *context, const char *db_name,
+ const char *table_name, List_iterator<Item> *it,
+ bool any_privileges, uint *hidden_bit_fields, bool returning_field)
+{
+ Field_iterator_table_ref field_iterator;
+ bool found;
+ char name_buff[SAFE_NAME_LEN+1];
+ DBUG_ENTER("insert_fields");
+ DBUG_PRINT("arena", ("stmt arena: %p",thd->stmt_arena));
+
+ if (db_name && lower_case_table_names)
+ {
+ /*
+ convert database to lower case for comparison
+ We can't do this in Item_field as this would change the
+ 'name' of the item which may be used in the select list
+ */
+ strmake_buf(name_buff, db_name);
+ my_casedn_str(files_charset_info, name_buff);
+ db_name= name_buff;
+ }
+
+ found= FALSE;
+
+ /*
+ If table names are qualified, then loop over all tables used in the query,
+ else treat natural joins as leaves and do not iterate over their underlying
+ tables.
+ */
+ TABLE_LIST *first= context->first_name_resolution_table;
+ TABLE_LIST *TABLE_LIST::* next= &TABLE_LIST::next_name_resolution_table;
+ if (table_name && !returning_field)
+ {
+ first= context->table_list;
+ next= &TABLE_LIST::next_local;
+ }
+ for (TABLE_LIST *tables= first; tables; tables= tables->*next)
+ {
+ Field *field;
+ TABLE *table= tables->table;
+
+ DBUG_ASSERT(tables->is_leaf_for_name_resolution());
+
+ if ((table_name && my_strcasecmp(table_alias_charset, table_name,
+ tables->alias.str)) ||
+ (db_name && strcmp(tables->db.str, db_name)))
+ continue;
+
+#ifndef NO_EMBEDDED_ACCESS_CHECKS
+ /*
+ Ensure that we have access rights to all fields to be inserted
+ the table 'tables'. Under some circumstances, this check may be skipped.
+
+ The check is skipped in the following cases:
+
+ - any_privileges is true
+
+ - the table is a derived table
+
+ - the table is a view with SELECT privilege
+
+ - the table is a base table with SELECT privilege
+ */
+ if (!any_privileges &&
+ !tables->is_derived() &&
+ !(tables->is_view() && (tables->grant.privilege & SELECT_ACL)) &&
+ !(table && (table->grant.privilege & SELECT_ACL)))
+ {
+ field_iterator.set(tables);
+ if (check_grant_all_columns(thd, SELECT_ACL, &field_iterator))
+ DBUG_RETURN(TRUE);
+ }
+#endif
+
+ /*
+ Update the tables used in the query based on the referenced fields. For
+ views and natural joins this update is performed inside the loop below.
+ */
+ if (table)
+ {
+ thd->lex->used_tables|= table->map;
+ thd->lex->current_select->select_list_tables|= table->map;
+ }
+
+ /*
+ Initialize a generic field iterator for the current table reference.
+ Notice that it is guaranteed that this iterator will iterate over the
+ fields of a single table reference, because 'tables' is a leaf (for
+ name resolution purposes).
+ */
+ field_iterator.set(tables);
+
+ for (; !field_iterator.end_of_fields(); field_iterator.next())
+ {
+ /*
+ field() is always NULL for views (see, e.g. Field_iterator_view or
+ Field_iterator_natural_join).
+ But view fields can never be invisible.
+ */
+ if ((field= field_iterator.field()) && field->invisible != VISIBLE)
+ continue;
+
+ Item *item;
+
+ if (!(item= field_iterator.create_item(thd)))
+ DBUG_RETURN(TRUE);
+
+ /* cache the table for the Item_fields inserted by expanding stars */
+ if (item->type() == Item::FIELD_ITEM && tables->cacheable_table)
+ ((Item_field *)item)->cached_table= tables;
+
+ if (!found)
+ {
+ found= TRUE;
+ it->replace(item); /* Replace '*' with the first found item. */
+ }
+ else
+ it->after(item); /* Add 'item' to the SELECT list. */
+
+ if (item->type() == Item::FIELD_ITEM && item->field_type() == MYSQL_TYPE_BIT)
+ (*hidden_bit_fields)++;
+
+#ifndef NO_EMBEDDED_ACCESS_CHECKS
+ /*
+ Set privilege information for the fields of newly created views.
+ We have that (any_priviliges == TRUE) if and only if we are creating
+ a view. In the time of view creation we can't use the MERGE algorithm,
+ therefore if 'tables' is itself a view, it is represented by a
+ temporary table. Thus in this case we can be sure that 'item' is an
+ Item_field.
+ */
+ if (any_privileges && !tables->is_with_table() && !tables->is_derived())
+ {
+ DBUG_ASSERT((tables->field_translation == NULL && table) ||
+ tables->is_natural_join);
+ DBUG_ASSERT(item->type() == Item::FIELD_ITEM);
+ Item_field *fld= (Item_field*) item;
+ const char *field_table_name= field_iterator.get_table_name();
+
+ if (!tables->schema_table &&
+ !(fld->have_privileges=
+ (get_column_grant(thd, field_iterator.grant(),
+ field_iterator.get_db_name(),
+ field_table_name, fld->field_name.str) &
+ VIEW_ANY_ACL)))
+ {
+ my_error(ER_TABLEACCESS_DENIED_ERROR, MYF(0), "ANY",
+ thd->security_ctx->priv_user,
+ thd->security_ctx->host_or_ip,
+ field_table_name);
+ DBUG_RETURN(TRUE);
+ }
+ }
+#endif
+
+ if ((field= field_iterator.field()))
+ {
+ field->table->mark_column_with_deps(field);
+ if (table)
+ table->covering_keys.intersect(field->part_of_key);
+ if (tables->is_natural_join)
+ {
+ TABLE *field_table;
+ /*
+ In this case we are sure that the column ref will not be created
+ because it was already created and stored with the natural join.
+ */
+ Natural_join_column *nj_col;
+ if (!(nj_col= field_iterator.get_natural_column_ref()))
+ DBUG_RETURN(TRUE);
+ DBUG_ASSERT(nj_col->table_field);
+ field_table= nj_col->table_ref->table;
+ if (field_table)
+ {
+ thd->lex->used_tables|= field_table->map;
+ thd->lex->current_select->select_list_tables|=
+ field_table->map;
+ field_table->covering_keys.intersect(field->part_of_key);
+ field_table->used_fields++;
+ }
+ }
+ }
+ else
+ thd->lex->used_tables|= item->used_tables();
+ thd->lex->current_select->cur_pos_in_select_list++;
+ }
+ /*
+ In case of stored tables, all fields are considered as used,
+ while in the case of views, the fields considered as used are the
+ ones marked in setup_tables during fix_fields of view columns.
+ For NATURAL joins, used_tables is updated in the IF above.
+ */
+ if (table)
+ table->used_fields= table->s->fields;
+ }
+ if (found)
+ DBUG_RETURN(FALSE);
+
+ /*
+ TODO: in the case when we skipped all columns because there was a
+ qualified '*', and all columns were coalesced, we have to give a more
+ meaningful message than ER_BAD_TABLE_ERROR.
+ */
+ if (!table_name)
+ my_error(ER_NO_TABLES_USED, MYF(0));
+ else if (!db_name && !thd->db.str)
+ my_error(ER_NO_DB_ERROR, MYF(0));
+ else
+ {
+ char name[FN_REFLEN];
+ my_snprintf(name, sizeof(name), "%s.%s",
+ db_name ? db_name : thd->get_db(), table_name);
+ my_error(ER_BAD_TABLE_ERROR, MYF(0), name);
+ }
+
+ DBUG_RETURN(TRUE);
+}
+
+
+/**
+ Wrap Item_ident
+
+ @param thd thread handle
+ @param conds pointer to the condition which should be wrapped
+*/
+
+void wrap_ident(THD *thd, Item **conds)
+{
+ Item_direct_ref_to_ident *wrapper;
+ DBUG_ASSERT((*conds)->type() == Item::FIELD_ITEM || (*conds)->type() == Item::REF_ITEM);
+ Query_arena *arena, backup;
+ arena= thd->activate_stmt_arena_if_needed(&backup);
+ if ((wrapper= new (thd->mem_root) Item_direct_ref_to_ident(thd, (Item_ident *) (*conds))))
+ (*conds)= (Item*) wrapper;
+ if (arena)
+ thd->restore_active_arena(arena, &backup);
+}
+
+/**
+ Prepare ON expression
+
+ @param thd Thread handle
+ @param table Pointer to table list
+ @param is_update Update flag
+
+ @retval TRUE error.
+ @retval FALSE OK.
+*/
+
+bool setup_on_expr(THD *thd, TABLE_LIST *table, bool is_update)
+{
+ uchar buff[STACK_BUFF_ALLOC]; // Max argument in function
+ if (check_stack_overrun(thd, STACK_MIN_SIZE, buff))
+ return TRUE; // Fatal error flag is set!
+ for(; table; table= table->next_local)
+ {
+ TABLE_LIST *embedded; /* The table at the current level of nesting. */
+ TABLE_LIST *embedding= table; /* The parent nested table reference. */
+ do
+ {
+ embedded= embedding;
+ if (embedded->on_expr)
+ {
+ thd->where="on clause";
+ embedded->on_expr->mark_as_condition_AND_part(embedded);
+ if (embedded->on_expr->fix_fields_if_needed_for_bool(thd,
+ &embedded->on_expr))
+ return TRUE;
+ }
+ /*
+ If it's a semi-join nest, fix its "left expression", as it is used by
+ the SJ-Materialization
+ */
+ if (embedded->sj_subq_pred)
+ {
+ Item **left_expr= embedded->sj_subq_pred->left_exp_ptr();
+ if ((*left_expr)->fix_fields_if_needed(thd, left_expr))
+ return TRUE;
+ }
+
+ embedding= embedded->embedding;
+ }
+ while (embedding &&
+ embedding->nested_join->join_list.head() == embedded);
+
+ if (table->is_merged_derived())
+ {
+ SELECT_LEX *select_lex= table->get_single_select();
+ setup_on_expr(thd, select_lex->get_table_list(), is_update);
+ }
+
+ /* process CHECK OPTION */
+ if (is_update)
+ {
+ TABLE_LIST *view= table->top_table();
+ if (view->effective_with_check)
+ {
+ if (view->prepare_check_option(thd))
+ return TRUE;
+ thd->change_item_tree(&table->check_option, view->check_option);
+ }
+ }
+ }
+ return FALSE;
+}
+
+/*
+ Fix all conditions and outer join expressions.
+
+ SYNOPSIS
+ setup_conds()
+ thd thread handler
+ tables list of tables for name resolving (select_lex->table_list)
+ leaves list of leaves of join table tree (select_lex->leaf_tables)
+ conds WHERE clause
+
+ DESCRIPTION
+ TODO
+
+ RETURN
+ TRUE if some error occurred (e.g. out of memory)
+ FALSE if all is OK
+*/
+
+int setup_conds(THD *thd, TABLE_LIST *tables, List<TABLE_LIST> &leaves,
+ COND **conds)
+{
+ SELECT_LEX *select_lex= thd->lex->current_select;
+ TABLE_LIST *table= NULL; // For HP compilers
+ /*
+ it_is_update set to TRUE when tables of primary SELECT_LEX (SELECT_LEX
+ which belong to LEX, i.e. most up SELECT) will be updated by
+ INSERT/UPDATE/LOAD
+ NOTE: using this condition helps to prevent call of prepare_check_option()
+ from subquery of VIEW, because tables of subquery belongs to VIEW
+ (see condition before prepare_check_option() call)
+ */
+ bool it_is_update= (select_lex == thd->lex->first_select_lex()) &&
+ thd->lex->which_check_option_applicable();
+ bool save_is_item_list_lookup= select_lex->is_item_list_lookup;
+ TABLE_LIST *derived= select_lex->master_unit()->derived;
+ DBUG_ENTER("setup_conds");
+
+ select_lex->is_item_list_lookup= 0;
+
+ thd->column_usage= MARK_COLUMNS_READ;
+ DBUG_PRINT("info", ("thd->column_usage: %d", thd->column_usage));
+ select_lex->cond_count= 0;
+ select_lex->between_count= 0;
+ select_lex->max_equal_elems= 0;
+
+ for (table= tables; table; table= table->next_local)
+ {
+ if (select_lex == thd->lex->first_select_lex() &&
+ select_lex->first_cond_optimization &&
+ table->merged_for_insert &&
+ table->prepare_where(thd, conds, FALSE))
+ goto err_no_arena;
+ }
+
+ if (*conds)
+ {
+ thd->where="where clause";
+ DBUG_EXECUTE("where",
+ print_where(*conds,
+ "WHERE in setup_conds",
+ QT_ORDINARY););
+ /*
+ Wrap alone field in WHERE clause in case it will be outer field of subquery
+ which need persistent pointer on it, but conds could be changed by optimizer
+ */
+ if ((*conds)->type() == Item::FIELD_ITEM && !derived)
+ wrap_ident(thd, conds);
+ (*conds)->mark_as_condition_AND_part(NO_JOIN_NEST);
+ if ((*conds)->fix_fields_if_needed_for_bool(thd, conds))
+ goto err_no_arena;
+ }
+
+ /*
+ Apply fix_fields() to all ON clauses at all levels of nesting,
+ including the ones inside view definitions.
+ */
+ if (setup_on_expr(thd, tables, it_is_update))
+ goto err_no_arena;
+
+ if (!thd->stmt_arena->is_conventional())
+ {
+ /*
+ We are in prepared statement preparation code => we should store
+ WHERE clause changing for next executions.
+
+ We do this ON -> WHERE transformation only once per PS/SP statement.
+ */
+ select_lex->where= *conds;
+ }
+ thd->lex->current_select->is_item_list_lookup= save_is_item_list_lookup;
+ DBUG_RETURN(MY_TEST(thd->is_error()));
+
+err_no_arena:
+ select_lex->is_item_list_lookup= save_is_item_list_lookup;
+ DBUG_RETURN(1);
+}
+
+
+/******************************************************************************
+** Fill a record with data (for INSERT or UPDATE)
+** Returns : 1 if some field has wrong type
+******************************************************************************/
+
+
+/**
+ Fill the fields of a table with the values of an Item list
+
+ @param thd thread handler
+ @param table_arg the table that is being modified
+ @param fields Item_fields list to be filled
+ @param values values to fill with
+ @param ignore_errors TRUE if we should ignore errors
+ @param update TRUE if update query
+
+ @details
+ fill_record() may set table->auto_increment_field_not_null and a
+ caller should make sure that it is reset after their last call to this
+ function.
+ default functions are executed for inserts.
+ virtual fields are always updated
+
+ @return Status
+ @retval true An error occurred.
+ @retval false OK.
+*/
+
+bool
+fill_record(THD *thd, TABLE *table_arg, List<Item> &fields, List<Item> &values,
+ bool ignore_errors, bool update)
+{
+ List_iterator_fast<Item> f(fields),v(values);
+ Item *value, *fld;
+ Item_field *field;
+ Field *rfield;
+ TABLE *table;
+ bool only_unvers_fields= update && table_arg->versioned();
+ bool save_abort_on_warning= thd->abort_on_warning;
+ bool save_no_errors= thd->no_errors;
+ DBUG_ENTER("fill_record");
+
+ thd->no_errors= ignore_errors;
+ /*
+ Reset the table->auto_increment_field_not_null as it is valid for
+ only one row.
+ */
+ if (fields.elements)
+ table_arg->auto_increment_field_not_null= FALSE;
+
+ while ((fld= f++))
+ {
+ if (!(field= fld->field_for_view_update()))
+ {
+ my_error(ER_NONUPDATEABLE_COLUMN, MYF(0), fld->name.str);
+ goto err;
+ }
+ value=v++;
+ DBUG_ASSERT(value);
+ rfield= field->field;
+ table= rfield->table;
+ if (table->next_number_field &&
+ rfield->field_index == table->next_number_field->field_index)
+ table->auto_increment_field_not_null= TRUE;
+ const bool skip_sys_field= rfield->vers_sys_field(); // TODO: && !thd->vers_modify_history() [MDEV-16546]
+ if ((rfield->vcol_info || skip_sys_field) &&
+ !value->vcol_assignment_allowed_value() &&
+ table->s->table_category != TABLE_CATEGORY_TEMPORARY)
+ {
+ push_warning_printf(thd, Sql_condition::WARN_LEVEL_WARN,
+ ER_WARNING_NON_DEFAULT_VALUE_FOR_GENERATED_COLUMN,
+ ER_THD(thd, ER_WARNING_NON_DEFAULT_VALUE_FOR_GENERATED_COLUMN),
+ rfield->field_name.str, table->s->table_name.str);
+ }
+ if (only_unvers_fields && !rfield->vers_update_unversioned())
+ only_unvers_fields= false;
+
+ if (rfield->stored_in_db())
+ {
+ if (!skip_sys_field &&
+ unlikely(value->save_in_field(rfield, 0) < 0) && !ignore_errors)
+ {
+ my_message(ER_UNKNOWN_ERROR, ER_THD(thd, ER_UNKNOWN_ERROR), MYF(0));
+ goto err;
+ }
+ /*
+ In sql MODE_SIMULTANEOUS_ASSIGNMENT,
+ move field pointer on value stored in record[1]
+ which contains row before update (see MDEV-13417)
+ */
+ if (update && thd->variables.sql_mode & MODE_SIMULTANEOUS_ASSIGNMENT)
+ rfield->move_field_offset((my_ptrdiff_t) (table->record[1] -
+ table->record[0]));
+ }
+ rfield->set_has_explicit_value();
+ }
+
+ if (update && thd->variables.sql_mode & MODE_SIMULTANEOUS_ASSIGNMENT)
+ {
+ // restore fields pointers on record[0]
+ f.rewind();
+ while ((fld= f++))
+ {
+ rfield= fld->field_for_view_update()->field;
+ if (rfield->stored_in_db())
+ {
+ table= rfield->table;
+ rfield->move_field_offset((my_ptrdiff_t) (table->record[0] -
+ table->record[1]));
+ }
+ }
+ }
+
+ if (update)
+ table_arg->evaluate_update_default_function();
+ else
+ if (table_arg->default_field &&
+ table_arg->update_default_fields(ignore_errors))
+ goto err;
+
+ if (table_arg->versioned() && !only_unvers_fields)
+ table_arg->vers_update_fields();
+ /* Update virtual fields */
+ if (table_arg->vfield &&
+ table_arg->update_virtual_fields(table_arg->file, VCOL_UPDATE_FOR_WRITE))
+ goto err;
+ thd->abort_on_warning= save_abort_on_warning;
+ thd->no_errors= save_no_errors;
+ DBUG_RETURN(thd->is_error());
+err:
+ DBUG_PRINT("error",("got error"));
+ thd->abort_on_warning= save_abort_on_warning;
+ thd->no_errors= save_no_errors;
+ if (fields.elements)
+ table_arg->auto_increment_field_not_null= FALSE;
+ DBUG_RETURN(TRUE);
+}
+
+
+/**
+ Prepare Item_field's for fill_record_n_invoke_before_triggers()
+
+ This means redirecting from table->field to
+ table->field_to_fill(), if needed.
+*/
+void switch_to_nullable_trigger_fields(List<Item> &items, TABLE *table)
+{
+ Field** field= table->field_to_fill();
+
+ /* True if we have NOT NULL fields and BEFORE triggers */
+ if (field != table->field)
+ {
+ List_iterator_fast<Item> it(items);
+ Item *item;
+
+ while ((item= it++))
+ item->walk(&Item::switch_to_nullable_fields_processor, 1, field);
+ table->triggers->reset_extra_null_bitmap();
+ }
+}
+
+
+/**
+ Prepare Virtual fields and field with default expressions to use
+ trigger fields
+
+ This means redirecting from table->field to
+ table->field_to_fill(), if needed.
+*/
+
+void switch_defaults_to_nullable_trigger_fields(TABLE *table)
+{
+ if (!table->default_field)
+ return; // no defaults
+
+ Field **trigger_field= table->field_to_fill();
+
+ /* True if we have NOT NULL fields and BEFORE triggers */
+ if (*trigger_field != *table->field)
+ {
+ for (Field **field_ptr= table->default_field; *field_ptr ; field_ptr++)
+ {
+ Field *field= (*field_ptr);
+ field->default_value->expr->walk(&Item::switch_to_nullable_fields_processor, 1, trigger_field);
+ *field_ptr= (trigger_field[field->field_index]);
+ }
+ }
+}
+
+
+/**
+ Test NOT NULL constraint after BEFORE triggers
+*/
+static bool not_null_fields_have_null_values(TABLE *table)
+{
+ Field **orig_field= table->field;
+ Field **filled_field= table->field_to_fill();
+
+ if (filled_field != orig_field)
+ {
+ THD *thd=table->in_use;
+ for (uint i=0; i < table->s->fields; i++)
+ {
+ Field *of= orig_field[i];
+ Field *ff= filled_field[i];
+ if (ff != of)
+ {
+ // copy after-update flags to of, copy before-update flags to ff
+ swap_variables(uint32, of->flags, ff->flags);
+ if (ff->is_real_null())
+ {
+ ff->set_notnull(); // for next row WHERE condition in UPDATE
+ if (convert_null_to_field_value_or_error(of) || thd->is_error())
+ return true;
+ }
+ }
+ }
+ }
+
+ return false;
+}
+
+/**
+ Fill fields in list with values from the list of items and invoke
+ before triggers.
+
+ @param thd thread context
+ @param table the table that is being modified
+ @param fields Item_fields list to be filled
+ @param values values to fill with
+ @param ignore_errors TRUE if we should ignore errors
+ @param event event type for triggers to be invoked
+
+ @detail
+ This function assumes that fields which values will be set and triggers
+ to be invoked belong to the same table, and that TABLE::record[0] and
+ record[1] buffers correspond to new and old versions of row respectively.
+
+ @return Status
+ @retval true An error occurred.
+ @retval false OK.
+*/
+
+bool
+fill_record_n_invoke_before_triggers(THD *thd, TABLE *table,
+ List<Item> &fields,
+ List<Item> &values, bool ignore_errors,
+ enum trg_event_type event)
+{
+ int result;
+ Table_triggers_list *triggers= table->triggers;
+
+ result= fill_record(thd, table, fields, values, ignore_errors,
+ event == TRG_EVENT_UPDATE);
+
+ if (!result && triggers)
+ {
+ if (triggers->process_triggers(thd, event, TRG_ACTION_BEFORE,
+ TRUE) ||
+ not_null_fields_have_null_values(table))
+ return TRUE;
+
+ /*
+ Re-calculate virtual fields to cater for cases when base columns are
+ updated by the triggers.
+ */
+ if (table->vfield && fields.elements)
+ {
+ Item *fld= (Item_field*) fields.head();
+ Item_field *item_field= fld->field_for_view_update();
+ if (item_field)
+ {
+ DBUG_ASSERT(table == item_field->field->table);
+ result|= table->update_virtual_fields(table->file,
+ VCOL_UPDATE_FOR_WRITE);
+ }
+ }
+ }
+ return result;
+}
+
+
+/**
+ Fill the field buffer of a table with the values of an Item list
+ All fields are given a value
+
+ @param thd thread handler
+ @param table_arg the table that is being modified
+ @param ptr pointer on pointer to record of fields
+ @param values values to fill with
+ @param ignore_errors TRUE if we should ignore errors
+ @param use_value forces usage of value of the items instead of result
+
+ @details
+ fill_record() may set table->auto_increment_field_not_null and a
+ caller should make sure that it is reset after their last call to this
+ function.
+
+ @return Status
+ @retval true An error occurred.
+ @retval false OK.
+*/
+
+bool
+fill_record(THD *thd, TABLE *table, Field **ptr, List<Item> &values,
+ bool ignore_errors, bool use_value)
+{
+ List_iterator_fast<Item> v(values);
+ List<TABLE> tbl_list;
+ Item *value;
+ Field *field;
+ bool abort_on_warning_saved= thd->abort_on_warning;
+ uint autoinc_index= table->next_number_field
+ ? table->next_number_field->field_index
+ : ~0U;
+ DBUG_ENTER("fill_record");
+ if (!*ptr)
+ {
+ /* No fields to update, quite strange!*/
+ DBUG_RETURN(0);
+ }
+
+ /*
+ On INSERT or UPDATE fields are checked to be from the same table,
+ thus we safely can take table from the first field.
+ */
+ DBUG_ASSERT((*ptr)->table == table);
+
+ /*
+ Reset the table->auto_increment_field_not_null as it is valid for
+ only one row.
+ */
+ table->auto_increment_field_not_null= FALSE;
+ while ((field = *ptr++) && ! thd->is_error())
+ {
+ /* Ensure that all fields are from the same table */
+ DBUG_ASSERT(field->table == table);
+
+ if (unlikely(field->invisible))
+ continue;
+
+ value=v++;
+
+ bool vers_sys_field= table->versioned() && field->vers_sys_field();
+
+ if (field->field_index == autoinc_index)
+ table->auto_increment_field_not_null= TRUE;
+ if ((unlikely(field->vcol_info) || (vers_sys_field && !ignore_errors)) &&
+ !value->vcol_assignment_allowed_value() &&
+ table->s->table_category != TABLE_CATEGORY_TEMPORARY)
+ {
+ push_warning_printf(thd, Sql_condition::WARN_LEVEL_WARN,
+ ER_WARNING_NON_DEFAULT_VALUE_FOR_GENERATED_COLUMN,
+ ER_THD(thd, ER_WARNING_NON_DEFAULT_VALUE_FOR_GENERATED_COLUMN),
+ field->field_name.str, table->s->table_name.str);
+ if (vers_sys_field)
+ continue;
+ }
+
+ if (use_value)
+ value->save_val(field);
+ else
+ if (value->save_in_field(field, 0) < 0)
+ goto err;
+ field->set_has_explicit_value();
+ }
+ /* Update virtual fields if there wasn't any errors */
+ if (!thd->is_error())
+ {
+ thd->abort_on_warning= FALSE;
+ if (table->versioned())
+ table->vers_update_fields();
+ if (table->vfield &&
+ table->update_virtual_fields(table->file, VCOL_UPDATE_FOR_WRITE))
+ goto err;
+ thd->abort_on_warning= abort_on_warning_saved;
+ }
+ DBUG_RETURN(thd->is_error());
+
+err:
+ thd->abort_on_warning= abort_on_warning_saved;
+ table->auto_increment_field_not_null= FALSE;
+ DBUG_RETURN(TRUE);
+}
+
+
+/*
+ Fill fields in an array with values from the list of items and invoke
+ before triggers.
+
+ @param thd thread context
+ @param table the table that is being modified
+ @param ptr the fields to be filled
+ @param values values to fill with
+ @param ignore_errors TRUE if we should ignore errors
+ @param event event type for triggers to be invoked
+
+ @detail
+ This function assumes that fields which values will be set and triggers
+ to be invoked belong to the same table, and that TABLE::record[0] and
+ record[1] buffers correspond to new and old versions of row respectively.
+
+ @return Status
+ @retval true An error occurred.
+ @retval false OK.
+*/
+
+bool
+fill_record_n_invoke_before_triggers(THD *thd, TABLE *table, Field **ptr,
+ List<Item> &values, bool ignore_errors,
+ enum trg_event_type event)
+{
+ bool result;
+ Table_triggers_list *triggers= table->triggers;
+
+ result= fill_record(thd, table, ptr, values, ignore_errors, FALSE);
+
+ if (!result && triggers && *ptr)
+ result= triggers->process_triggers(thd, event, TRG_ACTION_BEFORE, TRUE) ||
+ not_null_fields_have_null_values(table);
+ /*
+ Re-calculate virtual fields to cater for cases when base columns are
+ updated by the triggers.
+ */
+ if (!result && triggers && *ptr)
+ {
+ DBUG_ASSERT(table == (*ptr)->table);
+ if (table->vfield)
+ result= table->update_virtual_fields(table->file, VCOL_UPDATE_FOR_WRITE);
+ }
+ return result;
+
+}
+
+
+my_bool mysql_rm_tmp_tables(void)
+{
+ uint i, idx;
+ char path[FN_REFLEN], *tmpdir, path_copy[FN_REFLEN];
+ MY_DIR *dirp;
+ FILEINFO *file;
+ TABLE_SHARE share;
+ THD *thd;
+ DBUG_ENTER("mysql_rm_tmp_tables");
+
+ if (!(thd= new THD(0)))
+ DBUG_RETURN(1);
+ thd->thread_stack= (char*) &thd;
+ thd->store_globals();
+
+ for (i=0; i<=mysql_tmpdir_list.max; i++)
+ {
+ tmpdir=mysql_tmpdir_list.list[i];
+ /* See if the directory exists */
+ if (!(dirp = my_dir(tmpdir,MYF(MY_WME | MY_DONT_SORT))))
+ continue;
+
+ /* Remove all SQLxxx tables from directory */
+
+ for (idx=0 ; idx < (uint) dirp->number_of_files ; idx++)
+ {
+ file=dirp->dir_entry+idx;
+
+ if (!strncmp(file->name, tmp_file_prefix, tmp_file_prefix_length))
+ {
+ char *ext= fn_ext(file->name);
+ size_t ext_len= strlen(ext);
+ size_t path_len= my_snprintf(path, sizeof(path),
+ "%s%c%s", tmpdir, FN_LIBCHAR,
+ file->name);
+ if (!strcmp(reg_ext, ext))
+ {
+ /* We should cut file extention before deleting of table */
+ memcpy(path_copy, path, path_len - ext_len);
+ path_copy[path_len - ext_len]= 0;
+ init_tmp_table_share(thd, &share, "", 0, "", path_copy);
+ if (!open_table_def(thd, &share))
+ share.db_type()->drop_table(share.db_type(), path_copy);
+ free_table_share(&share);
+ }
+ /*
+ File can be already deleted by tmp_table.file->delete_table().
+ So we hide error messages which happnes during deleting of these
+ files(MYF(0)).
+ */
+ (void) mysql_file_delete(key_file_misc, path, MYF(0));
+ }
+ }
+ my_dirend(dirp);
+ }
+ delete thd;
+ DBUG_RETURN(0);
+}
+
+
+/*****************************************************************************
+ unireg support functions
+*****************************************************************************/
+
+int setup_ftfuncs(SELECT_LEX *select_lex)
+{
+ List_iterator<Item_func_match> li(*(select_lex->ftfunc_list)),
+ lj(*(select_lex->ftfunc_list));
+ Item_func_match *ftf, *ftf2;
+
+ while ((ftf=li++))
+ {
+ if (ftf->fix_index())
+ return 1;
+ lj.rewind();
+ while ((ftf2=lj++) != ftf)
+ {
+ if (ftf->eq(ftf2,1) && !ftf2->master)
+ ftf2->master=ftf;
+ }
+ }
+
+ return 0;
+}
+
+
+void cleanup_ftfuncs(SELECT_LEX *select_lex)
+{
+ List_iterator<Item_func_match> li(*(select_lex->ftfunc_list)),
+ lj(*(select_lex->ftfunc_list));
+ Item_func_match *ftf;
+
+ while ((ftf=li++))
+ {
+ ftf->cleanup();
+ }
+}
+
+
+int init_ftfuncs(THD *thd, SELECT_LEX *select_lex, bool no_order)
+{
+ if (select_lex->ftfunc_list->elements)
+ {
+ List_iterator<Item_func_match> li(*(select_lex->ftfunc_list));
+ Item_func_match *ifm;
+
+ while ((ifm=li++))
+ if (unlikely(!ifm->is_fixed()))
+ /*
+ it mean that clause where was FT function was removed, so we have
+ to remove the function from the list.
+ */
+ li.remove();
+ else if (ifm->init_search(thd, no_order))
+ return 1;
+ }
+ return 0;
+}
+
+
+bool is_equal(const LEX_CSTRING *a, const LEX_CSTRING *b)
+{
+ return a->length == b->length && !strncmp(a->str, b->str, a->length);
+}
+
+/*
+ Open and lock system tables for read.
+
+ SYNOPSIS
+ open_system_tables_for_read()
+ thd Thread context.
+ table_list List of tables to open.
+
+ NOTES
+ Caller should have used start_new_trans object to start a new
+ transcation when reading system tables.
+
+ Thanks to restrictions which we put on opening and locking of
+ system tables for writing, we can open and lock them for reading
+ even when we already have some other tables open and locked.
+ One should call thd->commit_whole_transaction_and_close_tables()
+ to close systems tables opened with this call.
+
+ NOTES
+ In some situations we use this function to open system tables for
+ writing. It happens, for examples, with statistical tables when
+ they are updated by an ANALYZE command. In these cases we should
+ guarantee that system tables will not be deadlocked.
+
+ RETURN
+ FALSE Success
+ TRUE Error
+*/
+
+bool
+open_system_tables_for_read(THD *thd, TABLE_LIST *table_list)
+{
+ Query_tables_list query_tables_list_backup;
+ LEX *lex= thd->lex;
+ DBUG_ENTER("open_system_tables_for_read");
+ DBUG_ASSERT(thd->internal_transaction());
+
+ /*
+ Besides using new Open_tables_state for opening system tables,
+ we also have to backup and reset/and then restore part of LEX
+ which is accessed by open_tables() in order to determine if
+ prelocking is needed and what tables should be added for it.
+ */
+ lex->reset_n_backup_query_tables_list(&query_tables_list_backup);
+ thd->lex->sql_command= SQLCOM_SELECT;
+
+ /*
+ Only use MYSQL_LOCK_IGNORE_TIMEOUT for tables opened for read.
+ This is to ensure that lock_wait_timeout is honored when trying
+ to update stats tables.
+ */
+ if (open_and_lock_tables(thd, table_list, FALSE,
+ (MYSQL_OPEN_IGNORE_FLUSH |
+ MYSQL_OPEN_IGNORE_LOGGING_FORMAT |
+ (table_list->lock_type < TL_WRITE_ALLOW_WRITE ?
+ MYSQL_LOCK_IGNORE_TIMEOUT : 0))))
+ {
+ lex->restore_backup_query_tables_list(&query_tables_list_backup);
+ DBUG_RETURN(TRUE);
+ }
+
+ for (TABLE_LIST *tables= table_list; tables; tables= tables->next_global)
+ {
+ DBUG_ASSERT(tables->table->s->table_category == TABLE_CATEGORY_SYSTEM);
+ tables->table->file->row_logging= 0;
+ tables->table->use_all_columns();
+ }
+ lex->restore_backup_query_tables_list(&query_tables_list_backup);
+
+ DBUG_RETURN(FALSE);
+}
+
+/**
+ A helper function to close a mysql.* table opened
+ in an auxiliary THD during bootstrap or in the main
+ connection, when we know that there are no locks
+ held by the connection due to a preceding implicit
+ commit.
+
+ We need this function since we'd like to not
+ just close the system table, but also release
+ the metadata lock on it.
+
+ Note, that in LOCK TABLES mode this function
+ does not release the metadata lock. But in this
+ mode the table can be opened only if it is locked
+ explicitly with LOCK TABLES.
+*/
+
+void
+close_mysql_tables(THD *thd)
+{
+ if (! thd->in_sub_stmt)
+ {
+ trans_commit_stmt(thd);
+ trans_commit(thd);
+ }
+ close_thread_tables(thd);
+ thd->release_transactional_locks();
+}
+
+/*
+ Open and lock one system table for update.
+
+ SYNOPSIS
+ open_system_table_for_update()
+ thd Thread context.
+ one_table Table to open.
+
+ NOTES
+ Table opened with this call should closed using close_thread_tables().
+
+ RETURN
+ 0 Error
+ # Pointer to TABLE object of system table
+*/
+
+TABLE *
+open_system_table_for_update(THD *thd, TABLE_LIST *one_table)
+{
+ DBUG_ENTER("open_system_table_for_update");
+
+ TABLE *table= open_ltable(thd, one_table, one_table->lock_type,
+ MYSQL_LOCK_IGNORE_TIMEOUT);
+ if (table)
+ {
+ DBUG_ASSERT(table->s->table_category == TABLE_CATEGORY_SYSTEM);
+ table->use_all_columns();
+ /* This table instance is not row logged */
+ table->file->row_logging= 0;
+ }
+ DBUG_RETURN(table);
+}
+
+/**
+ Open a log table.
+ Opening such tables is performed internally in the server
+ implementation, and is a 'nested' open, since some tables
+ might be already opened by the current thread.
+ The thread context before this call is saved, and is restored
+ when calling close_log_table().
+ @param thd The current thread
+ @param one_table Log table to open
+ @param backup [out] Temporary storage used to save the thread context
+*/
+TABLE *
+open_log_table(THD *thd, TABLE_LIST *one_table, Open_tables_backup *backup)
+{
+ uint flags= ( MYSQL_OPEN_IGNORE_GLOBAL_READ_LOCK |
+ MYSQL_LOCK_IGNORE_GLOBAL_READ_ONLY |
+ MYSQL_OPEN_IGNORE_FLUSH |
+ MYSQL_LOCK_IGNORE_TIMEOUT |
+ MYSQL_LOCK_LOG_TABLE);
+ TABLE *table;
+ /* Save value that is changed in mysql_lock_tables() */
+ ulonglong save_utime_after_lock= thd->utime_after_lock;
+ DBUG_ENTER("open_log_table");
+
+ thd->reset_n_backup_open_tables_state(backup);
+
+ if ((table= open_ltable(thd, one_table, one_table->lock_type, flags)))
+ {
+ DBUG_ASSERT(table->s->table_category == TABLE_CATEGORY_LOG);
+ DBUG_ASSERT(!table->file->row_logging);
+
+ /* Make sure all columns get assigned to a default value */
+ table->use_all_columns();
+ DBUG_ASSERT(table->s->no_replicate);
+ }
+ else
+ thd->restore_backup_open_tables_state(backup);
+
+ thd->utime_after_lock= save_utime_after_lock;
+ DBUG_RETURN(table);
+}
+
+/**
+ Close a log table.
+ The last table opened by open_log_table()
+ is closed, then the thread context is restored.
+ @param thd The current thread
+ @param backup [in] the context to restore.
+*/
+
+void close_log_table(THD *thd, Open_tables_backup *backup)
+{
+ /*
+ Inform the transaction handler that we are closing the
+ system tables and we don't need the read view anymore.
+ */
+ for (TABLE *table= thd->open_tables ; table ; table= table->next)
+ table->file->extra(HA_EXTRA_PREPARE_FOR_FORCED_CLOSE);
+ close_thread_tables(thd);
+ thd->restore_backup_open_tables_state(backup);
+}
+
+
+/**
+ @brief
+ Remove 'fixed' flag from items in a list
+
+ @param items list of items to un-fix
+
+ @details
+ This function sets to 0 the 'fixed' flag for items in the 'items' list.
+ It's needed to force correct marking of views' fields for INSERT/UPDATE
+ statements.
+*/
+
+void unfix_fields(List<Item> &fields)
+{
+ List_iterator<Item> li(fields);
+ Item *item;
+ while ((item= li++))
+ item->unfix_fields();
+}
+
+
+/**
+ Check result of dynamic column function and issue error if it is needed
+
+ @param rc The result code of dynamic column function
+
+ @return the result code which was get as an argument\
+*/
+
+int dynamic_column_error_message(enum_dyncol_func_result rc)
+{
+ switch (rc) {
+ case ER_DYNCOL_YES:
+ case ER_DYNCOL_OK:
+ case ER_DYNCOL_TRUNCATED:
+ break; // it is not an error
+ case ER_DYNCOL_FORMAT:
+ my_error(ER_DYN_COL_WRONG_FORMAT, MYF(0));
+ break;
+ case ER_DYNCOL_LIMIT:
+ my_error(ER_DYN_COL_IMPLEMENTATION_LIMIT, MYF(0));
+ break;
+ case ER_DYNCOL_RESOURCE:
+ my_error(ER_OUT_OF_RESOURCES, MYF(0));
+ break;
+ case ER_DYNCOL_DATA:
+ my_error(ER_DYN_COL_DATA, MYF(0));
+ break;
+ case ER_DYNCOL_UNKNOWN_CHARSET:
+ my_error(ER_DYN_COL_WRONG_CHARSET, MYF(0));
+ break;
+ }
+ return rc;
+}
+
+
+/**
+ Turn on the SELECT_DESCRIBE flag for the primary SELECT_LEX of the statement
+ being processed in case the statement is EXPLAIN UPDATE/DELETE.
+
+ @param lex current LEX
+*/
+
+void promote_select_describe_flag_if_needed(LEX *lex)
+{
+ if (lex->describe)
+ lex->first_select_lex()->options|= SELECT_DESCRIBE;
+}
+
+
+/**
+ @} (end of group Data_Dictionary)
+*/