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

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

1 files changed, 5859 insertions, 0 deletions

diff --git a/sql/field.h b/sql/field.h
new file mode 100644
index 00000000..9fe4db3b
--- /dev/null
+++ b/sql/field.h
@@ -0,0 +1,5859 @@
+#ifndef FIELD_INCLUDED
+#define FIELD_INCLUDED
+/* Copyright (c) 2000, 2015, Oracle and/or its affiliates.
+   Copyright (c) 2008, 2021, MariaDB Corporation.
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; version 2 of the License.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software
+   Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1335  USA */
+
+/*
+  Because of the function make_new_field() all field classes that have static
+  variables must declare the size_of() member function.
+*/
+
+#ifdef USE_PRAGMA_INTERFACE
+#pragma interface			/* gcc class implementation */
+#endif
+
+#include "mysqld.h"                             /* system_charset_info */
+#include "table.h"                              /* TABLE */
+#include "sql_string.h"                         /* String */
+#include "my_decimal.h"                         /* my_decimal */
+#include "sql_error.h"                          /* Sql_condition */
+#include "compat56.h"
+#include "sql_type.h"                           /* Type_std_attributes */
+#include "field_comp.h"
+
+class Send_field;
+class Copy_field;
+class Protocol;
+class Protocol_text;
+class Create_field;
+class Relay_log_info;
+class Field;
+class Column_statistics;
+class Column_statistics_collected;
+class Item_func;
+class Item_bool_func;
+class Item_equal;
+class Virtual_tmp_table;
+class Qualified_column_ident;
+class Table_ident;
+class SEL_ARG;
+class RANGE_OPT_PARAM;
+struct KEY_PART;
+struct SORT_FIELD;
+struct SORT_FIELD_ATTR;
+
+enum enum_check_fields
+{
+  CHECK_FIELD_IGNORE,
+  CHECK_FIELD_EXPRESSION,
+  CHECK_FIELD_WARN,
+  CHECK_FIELD_ERROR_FOR_NULL,
+};
+
+
+enum enum_conv_type
+{
+  CONV_TYPE_PRECISE,
+  CONV_TYPE_VARIANT,
+  CONV_TYPE_SUBSET_TO_SUPERSET,
+  CONV_TYPE_SUPERSET_TO_SUBSET,
+  CONV_TYPE_IMPOSSIBLE
+};
+
+
+class Conv_param
+{
+  uint16 m_table_def_flags;
+public:
+  Conv_param(uint16 table_def_flags)
+   :m_table_def_flags(table_def_flags)
+  { }
+  uint16 table_def_flags() const { return m_table_def_flags; }
+};
+
+
+class Conv_source: public Type_handler_hybrid_field_type
+{
+  uint16 m_metadata;
+  CHARSET_INFO *m_cs;
+public:
+  Conv_source(const Type_handler *h, uint16 metadata, CHARSET_INFO *cs)
+   :Type_handler_hybrid_field_type(h),
+    m_metadata(metadata),
+    m_cs(cs)
+  {
+    DBUG_ASSERT(cs);
+  }
+  uint16 metadata() const { return m_metadata; }
+  uint mbmaxlen() const { return m_cs->mbmaxlen; }
+};
+
+
+/*
+  Common declarations for Field and Item
+*/
+class Value_source
+{
+protected:
+
+  // Parameters for warning and note generation
+  class Warn_filter
+  {
+    bool m_want_warning_edom;
+    bool m_want_note_truncated_spaces;
+  public:
+    Warn_filter(bool want_warning_edom, bool want_note_truncated_spaces) :
+     m_want_warning_edom(want_warning_edom),
+     m_want_note_truncated_spaces(want_note_truncated_spaces)
+    { }
+    Warn_filter(const THD *thd);
+    bool want_warning_edom() const
+    { return m_want_warning_edom; }
+    bool want_note_truncated_spaces() const
+    { return m_want_note_truncated_spaces; }
+  };
+  class Warn_filter_all: public Warn_filter
+  {
+  public:
+    Warn_filter_all() :Warn_filter(true, true) { }
+  };
+
+  class Converter_double_to_longlong
+  {
+  protected:
+    bool m_error;
+    longlong m_result;
+  public:
+    Converter_double_to_longlong(double nr, bool unsigned_flag);
+    longlong result() const { return m_result; }
+    bool error() const { return m_error; }
+    void push_warning(THD *thd, double nr, bool unsigned_flag);
+  };
+  class Converter_double_to_longlong_with_warn:
+    public Converter_double_to_longlong
+  {
+  public:
+    Converter_double_to_longlong_with_warn(THD *thd, double nr,
+                                           bool unsigned_flag)
+      :Converter_double_to_longlong(nr, unsigned_flag)
+    {
+      if (m_error)
+        push_warning(thd, nr, unsigned_flag);
+    }
+    Converter_double_to_longlong_with_warn(double nr, bool unsigned_flag)
+      :Converter_double_to_longlong(nr, unsigned_flag)
+    {
+      if (m_error)
+        push_warning(current_thd, nr, unsigned_flag);
+    }
+  };
+
+  // String-to-number converters
+  class Converter_string_to_number
+  {
+  protected:
+    char *m_end_of_num; // Where the low-level conversion routine stopped
+    int m_error;        // The error code returned by the low-level routine
+    bool m_edom;        // If EDOM-alike error happened during conversion
+    /**
+      Check string-to-number conversion and produce a warning if
+      - could not convert any digits (EDOM-alike error)
+      - found garbage at the end of the string
+      - found extra spaces at the end (a note)
+      See also Field_num::check_edom_and_truncation() for a similar function.
+
+      @param thd         - the thread that will be used to generate warnings.
+                           Can be NULL (which means current_thd will be used
+                           if a warning is really necessary).
+      @param type        - name of the data type
+                           (e.g. "INTEGER", "DECIMAL", "DOUBLE")
+      @param cs          - character set of the original string
+      @param str         - the original string
+      @param end         - the end of the string
+      @param allow_notes - tells if trailing space notes should be displayed
+                           or suppressed.
+
+      Unlike Field_num::check_edom_and_truncation(), this function does not
+      distinguish between EDOM and truncation and reports the same warning for
+      both cases. Perhaps we should eventually print different warnings,
+      to make the explicit CAST work closer to the implicit cast in
+      Field_xxx::store().
+    */
+    void check_edom_and_truncation(THD *thd, Warn_filter filter,
+                                   const char *type,
+                                   CHARSET_INFO *cs,
+                                   const char *str,
+                                   size_t length) const;
+  public:
+    int error() const { return m_error; }
+  };
+
+  class Converter_strntod: public Converter_string_to_number
+  {
+    double m_result;
+  public:
+    Converter_strntod(CHARSET_INFO *cs, const char *str, size_t length)
+    {
+      m_result= cs->strntod((char *) str, length, &m_end_of_num, &m_error);
+      // strntod() does not set an error if the input string was empty
+      m_edom= m_error !=0 || str == m_end_of_num;
+    }
+    double result() const { return m_result; }
+  };
+
+  class Converter_string_to_longlong: public Converter_string_to_number
+  {
+  protected:
+    longlong m_result;
+  public:
+    longlong result() const { return m_result; }
+  };
+
+  class Converter_strntoll: public Converter_string_to_longlong
+  {
+  public:
+    Converter_strntoll(CHARSET_INFO *cs, const char *str, size_t length)
+    {
+      m_result= cs->strntoll(str, length, 10, &m_end_of_num, &m_error);
+      /*
+         All non-zero errors means EDOM error.
+         strntoll() does not set an error if the input string was empty.
+         Check it here.
+         Notice the different with the same condition in Converter_strntoll10.
+      */
+      m_edom= m_error != 0 || str == m_end_of_num;
+    }
+  };
+
+  class Converter_strtoll10: public Converter_string_to_longlong
+  {
+  public:
+    Converter_strtoll10(CHARSET_INFO *cs, const char *str, size_t length)
+    {
+      m_end_of_num= (char *) str + length;
+      m_result= cs->strtoll10(str, &m_end_of_num, &m_error);
+      /*
+        Negative error means "good negative number".
+        Only a positive m_error value means a real error.
+        strtoll10() sets error to MY_ERRNO_EDOM in case of an empty string,
+        so we don't have to additionally catch empty strings here.
+      */
+      m_edom= m_error > 0;
+    }
+  };
+
+  class Converter_str2my_decimal: public Converter_string_to_number
+  {
+  public:
+    Converter_str2my_decimal(uint mask,
+                             CHARSET_INFO *cs, const char *str, size_t length,
+                             my_decimal *buf)
+    {
+      DBUG_ASSERT(length < UINT_MAX32);
+      m_error= str2my_decimal(mask, str, length, cs,
+                              buf, (const char **) &m_end_of_num);
+      // E_DEC_TRUNCATED means a very minor truncation: '1e-100' -> 0
+      m_edom= m_error && m_error != E_DEC_TRUNCATED;
+    }
+  };
+
+
+  // String-to-number converters with automatic warning generation
+  class Converter_strntod_with_warn: public Converter_strntod
+  {
+  public:
+    Converter_strntod_with_warn(THD *thd, Warn_filter filter,
+                                CHARSET_INFO *cs,
+                                const char *str, size_t length)
+      :Converter_strntod(cs, str, length)
+    {
+      check_edom_and_truncation(thd, filter, "DOUBLE", cs, str, length);
+    }
+  };
+
+  class Converter_strntoll_with_warn: public Converter_strntoll
+  {
+  public:
+    Converter_strntoll_with_warn(THD *thd, Warn_filter filter,
+                                 CHARSET_INFO *cs,
+                                 const char *str, size_t length)
+      :Converter_strntoll(cs, str, length)
+    {
+      check_edom_and_truncation(thd, filter, "INTEGER", cs, str, length);
+    }
+  };
+
+  class Converter_strtoll10_with_warn: public Converter_strtoll10
+  {
+  public:
+    Converter_strtoll10_with_warn(THD *thd, Warn_filter filter,
+                                 CHARSET_INFO *cs,
+                                 const char *str, size_t length)
+      :Converter_strtoll10(cs, str, length)
+    {
+      check_edom_and_truncation(thd, filter, "INTEGER", cs, str, length);
+    }
+  };
+
+  class Converter_str2my_decimal_with_warn: public Converter_str2my_decimal
+  {
+  public:
+    Converter_str2my_decimal_with_warn(THD *thd, Warn_filter filter,
+                                       uint mask, CHARSET_INFO *cs,
+                                       const char *str, size_t length,
+                                       my_decimal *buf)
+     :Converter_str2my_decimal(mask, cs, str, length, buf)
+    {
+      check_edom_and_truncation(thd, filter, "DECIMAL", cs, str, length);
+    }
+  };
+
+
+  // String-to-number conversion methods for the old code compatibility
+  longlong longlong_from_string_with_check(CHARSET_INFO *cs, const char *cptr,
+                                           const char *end) const
+  {
+    /*
+      TODO: Give error if we wanted a signed integer and we got an unsigned
+      one
+
+      Notice, longlong_from_string_with_check() honors thd->no_error, because
+      it's used to handle queries like this:
+        SELECT COUNT(@@basedir);
+      and is called when Item_func_get_system_var::update_null_value()
+      suppresses warnings and then calls val_int().
+      The other methods {double|decimal}_from_string_with_check() ignore
+      thd->no_errors, because they are not used for update_null_value()
+      and they always allow all kind of warnings.
+    */
+    THD *thd= current_thd;
+    return Converter_strtoll10_with_warn(thd, Warn_filter(thd),
+                                         cs, cptr, end - cptr).result();
+  }
+
+  double double_from_string_with_check(CHARSET_INFO *cs, const char *cptr,
+                                       const char *end) const
+  {
+    return Converter_strntod_with_warn(NULL, Warn_filter_all(),
+                                       cs, cptr, end - cptr).result();
+  }
+  my_decimal *decimal_from_string_with_check(my_decimal *decimal_value,
+                                             CHARSET_INFO *cs,
+                                             const char *cptr,
+                                             const char *end)
+  {
+    Converter_str2my_decimal_with_warn(NULL, Warn_filter_all(),
+                                       E_DEC_FATAL_ERROR & ~E_DEC_BAD_NUM,
+                                       cs, cptr, end - cptr, decimal_value);
+    return decimal_value;
+  }
+
+  longlong longlong_from_hex_hybrid(const char *str, size_t length)
+  {
+    const char *end= str + length;
+    const char *ptr= end - MY_MIN(length, sizeof(longlong));
+    ulonglong value= 0;
+    for ( ; ptr != end ; ptr++)
+      value= (value << 8) + (ulonglong) (uchar) *ptr;
+    return (longlong) value;
+  }
+
+  longlong longlong_from_string_with_check(const String *str) const
+  {
+    return longlong_from_string_with_check(str->charset(),
+                                           str->ptr(), str->end());
+  }
+  double double_from_string_with_check(const String *str) const
+  {
+    return double_from_string_with_check(str->charset(),
+                                         str->ptr(), str->end());
+  }
+  my_decimal *decimal_from_string_with_check(my_decimal *decimal_value,
+                                             const String *str)
+  {
+    return decimal_from_string_with_check(decimal_value, str->charset(),
+                                          str->ptr(), str->end());
+  }
+  // End of String-to-number conversion methods
+
+public:
+  /*
+    The enumeration Subst_constraint is currently used only in implementations
+    of the virtual function subst_argument_checker.
+  */
+  enum Subst_constraint
+  {
+    ANY_SUBST,           /* Any substitution for a field is allowed  */
+    IDENTITY_SUBST       /* Substitution for a field is allowed if any two
+                            different values of the field type are not equal */
+  };
+  /*
+    Item context attributes.
+    Comparison functions pass their attributes to propagate_equal_fields().
+    For example, for string comparison, the collation of the comparison
+    operation is important inside propagate_equal_fields().
+  */
+  class Context
+  {
+    /*
+      Which type of propagation is allowed:
+      - ANY_SUBST (loose equality, according to the collation), or
+      - IDENTITY_SUBST (strict binary equality).
+    */
+    Subst_constraint m_subst_constraint;
+    /*
+      Comparison type.
+      Important only when ANY_SUBSTS.
+    */
+    const Type_handler *m_compare_handler;
+    /*
+      Collation of the comparison operation.
+      Important only when ANY_SUBST.
+    */
+    CHARSET_INFO *m_compare_collation;
+  public:
+    Context(Subst_constraint subst, const Type_handler *h, CHARSET_INFO *cs)
+      :m_subst_constraint(subst),
+       m_compare_handler(h),
+       m_compare_collation(cs)
+    { DBUG_ASSERT(h == h->type_handler_for_comparison()); }
+    Subst_constraint subst_constraint() const { return m_subst_constraint; }
+    const Type_handler *compare_type_handler() const
+    {
+      DBUG_ASSERT(m_subst_constraint == ANY_SUBST);
+      return m_compare_handler;
+    }
+    CHARSET_INFO *compare_collation() const
+    {
+      DBUG_ASSERT(m_subst_constraint == ANY_SUBST);
+      return m_compare_collation;
+    }
+  };
+  class Context_identity: public Context
+  { // Use this to request only exact value, no invariants.
+  public:
+     Context_identity()
+      :Context(IDENTITY_SUBST, &type_handler_long_blob, &my_charset_bin) { }
+  };
+  class Context_boolean: public Context
+  { // Use this when an item is [a part of] a boolean expression
+  public:
+    Context_boolean()
+      :Context(ANY_SUBST, &type_handler_slonglong, &my_charset_bin) { }
+  };
+};
+
+
+#define STORAGE_TYPE_MASK 7
+#define COLUMN_FORMAT_MASK 7
+#define COLUMN_FORMAT_SHIFT 3
+
+/* The length of the header part for each virtual column in the .frm file */
+#define FRM_VCOL_OLD_HEADER_SIZE(b) (3 + MY_TEST(b))
+#define FRM_VCOL_NEW_BASE_SIZE 16
+#define FRM_VCOL_NEW_HEADER_SIZE 6
+
+class Count_distinct_field;
+
+struct ha_field_option_struct;
+
+struct st_cache_field;
+int field_conv(Field *to,Field *from);
+int truncate_double(double *nr, uint field_length, uint dec,
+                    bool unsigned_flag, double max_value);
+
+inline uint get_enum_pack_length(int elements)
+{
+  return elements < 256 ? 1 : 2;
+}
+
+inline uint get_set_pack_length(int elements)
+{
+  uint len= (elements + 7) / 8;
+  return len > 4 ? 8 : len;
+}
+
+
+/**
+  Tests if field type is temporal and has date part,
+  i.e. represents DATE, DATETIME or TIMESTAMP types in SQL.
+
+  @param type    Field type, as returned by field->type().
+  @retval true   If field type is temporal type with date part.
+  @retval false  If field type is not temporal type with date part.
+*/
+inline bool is_temporal_type_with_date(enum_field_types type)
+{
+  switch (type)
+  {
+  case MYSQL_TYPE_DATE:
+  case MYSQL_TYPE_DATETIME:
+  case MYSQL_TYPE_TIMESTAMP:
+    return true;
+  case MYSQL_TYPE_DATETIME2:
+  case MYSQL_TYPE_TIMESTAMP2:
+    DBUG_ASSERT(0); // field->real_type() should not get to here.
+    return false;
+  default:
+    return false;
+  }
+}
+
+
+enum enum_vcol_info_type
+{
+  VCOL_GENERATED_VIRTUAL, VCOL_GENERATED_STORED,
+  VCOL_DEFAULT, VCOL_CHECK_FIELD, VCOL_CHECK_TABLE,
+  /* Additional types should be added here */
+  /* Following is the highest value last   */
+  VCOL_TYPE_NONE = 127 // Since the 0 value is already in use
+};
+
+static inline const char *vcol_type_name(enum_vcol_info_type type)
+{
+  switch (type)
+  {
+  case VCOL_GENERATED_VIRTUAL:
+  case VCOL_GENERATED_STORED:
+    return "GENERATED ALWAYS AS";
+  case VCOL_DEFAULT:
+    return "DEFAULT";
+  case VCOL_CHECK_FIELD:
+  case VCOL_CHECK_TABLE:
+    return "CHECK";
+  case VCOL_TYPE_NONE:
+    return "UNTYPED";
+  }
+  return 0;
+}
+
+/*
+  Flags for Virtual_column_info. If none is set, the expression must be
+  a constant with no side-effects, so it's calculated at CREATE TABLE time,
+  stored in table->record[2], and not recalculated for every statement.
+*/
+#define VCOL_FIELD_REF         1
+#define VCOL_NON_DETERMINISTIC 2
+#define VCOL_SESSION_FUNC      4  /* uses session data, e.g. USER or DAYNAME */
+#define VCOL_TIME_FUNC         8
+#define VCOL_AUTO_INC         16
+#define VCOL_IMPOSSIBLE       32
+#define VCOL_NOT_VIRTUAL      64  /* Function can't be virtual */
+#define VCOL_CHECK_CONSTRAINT_IF_NOT_EXISTS 128
+
+#define VCOL_NOT_STRICTLY_DETERMINISTIC                       \
+  (VCOL_NON_DETERMINISTIC | VCOL_TIME_FUNC | VCOL_SESSION_FUNC)
+
+/*
+  Virtual_column_info is the class to contain additional
+  characteristics that is specific for a virtual/computed
+  field such as:
+   - the defining expression that is evaluated to compute the value
+  of the field 
+  - whether the field is to be stored in the database
+  - whether the field is used in a partitioning expression
+*/
+
+class Virtual_column_info: public Sql_alloc,
+                           private Type_handler_hybrid_field_type
+{
+private:
+  enum_vcol_info_type vcol_type; /* Virtual column expression type */
+  /*
+    The following data is only updated by the parser and read
+    when a Create_field object is created/initialized.
+  */
+  /* Flag indicating that the field used in a partitioning expression */
+  bool in_partitioning_expr;
+
+public:
+  /* Flag indicating  that the field is physically stored in the database */
+  bool stored_in_db;
+  bool utf8;                                    /* Already in utf8 */
+  bool automatic_name;
+  Item *expr;
+  Lex_ident name;                               /* Name of constraint */
+  /* see VCOL_* (VCOL_FIELD_REF, ...) */
+  uint flags;
+
+  Virtual_column_info()
+   :Type_handler_hybrid_field_type(&type_handler_null),
+    vcol_type((enum_vcol_info_type)VCOL_TYPE_NONE),
+    in_partitioning_expr(FALSE), stored_in_db(FALSE),
+    utf8(TRUE), automatic_name(FALSE), expr(NULL), flags(0)
+  {
+    name.str= NULL;
+    name.length= 0;
+  };
+  Virtual_column_info* clone(THD *thd);
+  ~Virtual_column_info() {};
+  enum_vcol_info_type get_vcol_type() const
+  {
+    return vcol_type;
+  }
+  void set_vcol_type(enum_vcol_info_type v_type)
+  {
+    vcol_type= v_type;
+  }
+  const char *get_vcol_type_name() const
+  {
+    DBUG_ASSERT(vcol_type != VCOL_TYPE_NONE);
+    return vcol_type_name(vcol_type);
+  }
+  void set_handler(const Type_handler *handler)
+  {
+    /* Calling this function can only be done once. */
+    DBUG_ASSERT(type_handler() == &type_handler_null);
+    Type_handler_hybrid_field_type::set_handler(handler);
+  }
+  bool is_stored() const
+  {
+    return stored_in_db;
+  }
+  void set_stored_in_db_flag(bool stored)
+  {
+    stored_in_db= stored;
+  }
+  bool is_in_partitioning_expr() const
+  {
+    return in_partitioning_expr;
+  }
+  void mark_as_in_partitioning_expr()
+  {
+    in_partitioning_expr= TRUE;
+  }
+  inline bool is_equal(const Virtual_column_info* vcol) const;
+  inline void print(String*);
+};
+
+class Binlog_type_info
+{
+public:
+   enum binlog_sign_t
+   {
+     SIGN_SIGNED,
+     SIGN_UNSIGNED,
+     SIGN_NOT_APPLICABLE // for non-numeric types
+   };
+   uchar m_type_code;     // according to Field::binlog_type()
+  /**
+     Retrieve the field metadata for fields.
+  */
+   uint16 m_metadata;
+   uint8 m_metadata_size;
+   binlog_sign_t m_signedness;
+   CHARSET_INFO *m_cs; // NULL if not relevant
+   TYPELIB *m_enum_typelib; // NULL if not relevant
+   TYPELIB *m_set_typelib; // NULL if not relevant
+   uchar m_geom_type; // Non-geometry fields can return 0
+   Binlog_type_info(uchar type_code,
+                    uint16 metadata,
+                    uint8 metadata_size)
+    :m_type_code(type_code),
+     m_metadata(metadata),
+     m_metadata_size(metadata_size),
+     m_signedness(SIGN_NOT_APPLICABLE),
+     m_cs(NULL),
+     m_enum_typelib(NULL),
+     m_set_typelib(NULL),
+     m_geom_type(0)
+    {};
+   Binlog_type_info(uchar type_code, uint16 metadata,
+                   uint8 metadata_size,
+                   binlog_sign_t signedness)
+    :m_type_code(type_code),
+     m_metadata(metadata),
+     m_metadata_size(metadata_size),
+     m_signedness(signedness),
+     m_cs(NULL),
+     m_enum_typelib(NULL),
+     m_set_typelib(NULL),
+     m_geom_type(0)
+    {};
+   Binlog_type_info(uchar type_code, uint16 metadata,
+                   uint8 metadata_size,
+                   CHARSET_INFO *cs)
+    :m_type_code(type_code),
+     m_metadata(metadata),
+     m_metadata_size(metadata_size),
+     m_signedness(SIGN_NOT_APPLICABLE),
+     m_cs(cs),
+     m_enum_typelib(NULL),
+     m_set_typelib(NULL),
+     m_geom_type(0)
+    {};
+   Binlog_type_info(uchar type_code, uint16 metadata,
+                   uint8 metadata_size,
+                   CHARSET_INFO *cs,
+                   TYPELIB *t_enum, TYPELIB *t_set)
+    :m_type_code(type_code),
+     m_metadata(metadata),
+     m_metadata_size(metadata_size),
+     m_signedness(SIGN_NOT_APPLICABLE),
+     m_cs(cs),
+     m_enum_typelib(t_enum),
+     m_set_typelib(t_set),
+     m_geom_type(0)
+    {};
+   Binlog_type_info(uchar type_code, uint16 metadata,
+                   uint8 metadata_size, CHARSET_INFO *cs,
+                   uchar geom_type)
+    :m_type_code(type_code),
+     m_metadata(metadata),
+     m_metadata_size(metadata_size),
+     m_signedness(SIGN_NOT_APPLICABLE),
+     m_cs(cs),
+     m_enum_typelib(NULL),
+     m_set_typelib(NULL),
+     m_geom_type(geom_type)
+    {};
+  static void *operator new(size_t size, MEM_ROOT *mem_root) throw ()
+  { return alloc_root(mem_root, size); }
+};
+
+
+class Binlog_type_info_fixed_string: public Binlog_type_info
+{
+public:
+  Binlog_type_info_fixed_string(uchar type_code,
+                                uint32 octet_length,
+                                CHARSET_INFO *cs);
+};
+
+
+class Field: public Value_source
+{
+  Field(const Item &);				/* Prevent use of these */
+  void operator=(Field &);
+protected:
+  int save_in_field_str(Field *to)
+  {
+    StringBuffer<MAX_FIELD_WIDTH> result(charset());
+    val_str(&result);
+    return to->store(result.ptr(), result.length(), charset());
+  }
+  void error_generated_column_function_is_not_allowed(THD *thd, bool error)
+                                                      const;
+  static void do_field_eq(Copy_field *copy);
+  static void do_field_int(Copy_field *copy);
+  static void do_field_real(Copy_field *copy);
+  static void do_field_string(Copy_field *copy);
+  static void do_field_date(Copy_field *copy);
+  static void do_field_temporal(Copy_field *copy, date_mode_t fuzzydate);
+  static void do_field_datetime(Copy_field *copy);
+  static void do_field_timestamp(Copy_field *copy);
+  static void do_field_decimal(Copy_field *copy);
+public:
+  static void *operator new(size_t size, MEM_ROOT *mem_root) throw ()
+  { return alloc_root(mem_root, size); }
+  static void *operator new(size_t size) throw ()
+  {
+    DBUG_ASSERT(size < UINT_MAX32);
+    return thd_alloc(current_thd, (uint) size);
+  }
+  static void operator delete(void *ptr_arg, size_t size) { TRASH_FREE(ptr_arg, size); }
+  static void operator delete(void *ptr, MEM_ROOT *mem_root)
+  { DBUG_ASSERT(0); }
+
+  bool marked_for_read() const;
+  bool marked_for_write_or_computed() const;
+
+  /**
+     Used by System Versioning.
+   */
+  virtual void set_max()
+  { DBUG_ASSERT(0); }
+  virtual bool is_max()
+  { DBUG_ASSERT(0); return false; }
+
+  uchar		*ptr;			// Position to field in record
+
+  field_visibility_t invisible;
+  /**
+     Byte where the @c NULL bit is stored inside a record. If this Field is a
+     @c NOT @c NULL field, this member is @c NULL.
+  */
+  uchar		*null_ptr;
+  /*
+    Note that you can use table->in_use as replacement for current_thd member
+    only inside of val_*() and store() members (e.g. you can't use it in cons)
+  */
+  TABLE *table;                                 // Pointer for table
+  TABLE *orig_table;                            // Pointer to original table
+  const char * const *table_name;               // Pointer to alias in TABLE
+  LEX_CSTRING field_name;
+  LEX_CSTRING comment;
+  /** reference to the list of options or NULL */
+  engine_option_value *option_list;
+  ha_field_option_struct *option_struct;   /* structure with parsed options */
+  /* Field is part of the following keys */
+  key_map	key_start, part_of_key, part_of_key_not_clustered;
+
+  /*
+    Bitmap of indexes that have records ordered by col1, ... this_field, ...
+
+    For example, INDEX (col(prefix_n)) is not present in col.part_of_sortkey.
+  */
+  key_map       part_of_sortkey;
+  /*
+    We use three additional unireg types for TIMESTAMP to overcome limitation
+    of current binary format of .frm file. We'd like to be able to support
+    NOW() as default and on update value for such fields but unable to hold
+    this info anywhere except unireg_check field. This issue will be resolved
+    in more clean way with transition to new text based .frm format.
+    See also comment for Field_timestamp::Field_timestamp().
+  */
+  enum utype  {
+    NONE=0,
+    NEXT_NUMBER=15,             // AUTO_INCREMENT
+    TIMESTAMP_OLD_FIELD=18,     // TIMESTAMP created before 4.1.3
+    TIMESTAMP_DN_FIELD=21,      // TIMESTAMP DEFAULT NOW()
+    TIMESTAMP_UN_FIELD=22,      // TIMESTAMP ON UPDATE NOW()
+    TIMESTAMP_DNUN_FIELD=23,    // TIMESTAMP DEFAULT NOW() ON UPDATE NOW()
+    TMYSQL_COMPRESSED= 24,      // Compatibility with TMySQL
+    };
+  enum imagetype { itRAW, itMBR};
+
+  utype		unireg_check;
+  uint32	field_length;		// Length of field
+  uint32	flags;
+  uint16        field_index;            // field number in fields array
+  uchar		null_bit;		// Bit used to test null bit
+  /**
+     If true, this field was created in create_tmp_field_from_item from a NULL
+     value. This means that the type of the field is just a guess, and the type
+     may be freely coerced to another type.
+
+     @see create_tmp_field_from_item
+     @see Item_type_holder::get_real_type
+
+   */
+  bool is_created_from_null_item;
+
+  /* 
+    Selectivity of the range condition over this field.
+    When calculating this selectivity a range predicate
+    is taken into account only if:
+    - it is extracted from the WHERE clause
+    - it depends only on the table the field belongs to 
+  */
+  double cond_selectivity;
+
+  /* 
+    The next field in the class of equal fields at the top AND level
+    of the WHERE clause
+  */ 
+  Field *next_equal_field;
+
+  /*
+    This structure is used for statistical data on the column
+    that has been read from the statistical table column_stat
+  */ 
+  Column_statistics *read_stats;
+  /*
+    This structure is used for statistical data on the column that
+    is collected by the function collect_statistics_for_table
+  */
+  Column_statistics_collected *collected_stats;
+
+  /* 
+    This is additional data provided for any computed(virtual) field,
+    default function or check constraint.
+    In particular it includes a pointer to the item by which this field
+    can be computed from other fields.
+  */
+  Virtual_column_info *vcol_info, *check_constraint, *default_value;
+
+  Field(uchar *ptr_arg,uint32 length_arg,uchar *null_ptr_arg,
+        uchar null_bit_arg, utype unireg_check_arg,
+        const LEX_CSTRING *field_name_arg);
+  virtual ~Field() {}
+
+  virtual Type_numeric_attributes type_numeric_attributes() const
+  {
+    return Type_numeric_attributes(field_length, decimals(), is_unsigned());
+  }
+  Type_std_attributes type_std_attributes() const
+  {
+    return Type_std_attributes(type_numeric_attributes(), dtcollation());
+  }
+
+  bool is_unsigned() const { return flags & UNSIGNED_FLAG; }
+
+  /**
+    Convenience definition of a copy function returned by
+    Field::get_copy_func()
+  */
+  typedef void Copy_func(Copy_field*);
+  virtual Copy_func *get_copy_func(const Field *from) const= 0;
+  virtual Copy_func *get_copy_func_to(const Field *to) const
+  {
+    return to->get_copy_func(this);
+  }
+  /* Store functions returns 1 on overflow and -1 on fatal error */
+  virtual int  store_field(Field *from) { return from->save_in_field(this); }
+  virtual int  save_in_field(Field *to)= 0;
+  /**
+    Check if it is possible just copy the value
+    of the field 'from' to the field 'this', e.g. for
+      INSERT INTO t1 (field1) SELECT field2 FROM t2;
+    @param from   - The field to copy from
+    @retval true  - it is possible to just copy value of 'from' to 'this'
+    @retval false - conversion is needed
+  */
+  virtual bool memcpy_field_possible(const Field *from) const= 0;
+  virtual bool make_empty_rec_store_default_value(THD *thd, Item *item);
+  virtual void make_empty_rec_reset(THD *thd)
+  {
+    reset();
+  }
+  virtual int  store(const char *to, size_t length,CHARSET_INFO *cs)=0;
+  /*
+    This is used by engines like CSV and Federated to signal the field
+    that the data is going to be in text (rather than binary) representation,
+    even if cs points to &my_charset_bin.
+
+    If a Field distinguishes between text and binary formats (e.g. INET6),
+    we cannot call store(str,length,&my_charset_bin),
+    to avoid "field" mis-interpreting the data format as binary.
+  */
+  virtual int  store_text(const char *to, size_t length, CHARSET_INFO *cs)
+  {
+    return store(to, length, cs);
+  }
+  virtual int  store_binary(const char *to, size_t length)
+  {
+    return store(to, length, &my_charset_bin);
+  }
+  virtual int  store_hex_hybrid(const char *str, size_t length);
+  virtual int  store(double nr)=0;
+  virtual int  store(longlong nr, bool unsigned_val)=0;
+  virtual int  store_decimal(const my_decimal *d)=0;
+  virtual int  store_time_dec(const MYSQL_TIME *ltime, uint dec);
+  virtual int  store_timestamp_dec(const timeval &ts, uint dec);
+  int store_timestamp(my_time_t timestamp, ulong sec_part)
+  {
+    return store_timestamp_dec(Timeval(timestamp, sec_part),
+                               TIME_SECOND_PART_DIGITS);
+  }
+  /**
+    Store a value represented in native format
+  */
+  virtual int store_native(const Native &value)
+  {
+    DBUG_ASSERT(0);
+    reset();
+    return 0;
+  }
+  int store_time(const MYSQL_TIME *ltime)
+  { return store_time_dec(ltime, TIME_SECOND_PART_DIGITS); }
+  int store(const char *to, size_t length, CHARSET_INFO *cs,
+            enum_check_fields check_level);
+  int store_text(const char *to, size_t length, CHARSET_INFO *cs,
+                 enum_check_fields check_level);
+  int store(const LEX_STRING *ls, CHARSET_INFO *cs)
+  {
+    DBUG_ASSERT(ls->length < UINT_MAX32);
+    return store(ls->str, (uint) ls->length, cs);
+  }
+  int store(const LEX_CSTRING *ls, CHARSET_INFO *cs)
+  {
+    DBUG_ASSERT(ls->length < UINT_MAX32);
+    return store(ls->str, (uint) ls->length, cs);
+  }
+  int store(const LEX_CSTRING &ls, CHARSET_INFO *cs)
+  {
+    DBUG_ASSERT(ls.length < UINT_MAX32);
+    return store(ls.str, (uint) ls.length, cs);
+  }
+
+  /*
+    @brief
+      Store minimum/maximum value of a column in the statistics table.
+    @param
+      field                  statistical table field
+      str                    value buffer
+  */
+  virtual int store_to_statistical_minmax_field(Field *field, String *str);
+
+  /*
+    @brief
+      Store minimum/maximum value of a column from the statistical table.
+    @param
+      field                  statistical table field
+      str                    value buffer
+  */
+  virtual int store_from_statistical_minmax_field(Field *field, String *str);
+
+#ifdef HAVE_MEM_CHECK
+  /**
+    Mark unused memory in the field as defined. Mainly used to ensure
+    that if we write full field to disk (for example in
+    Count_distinct_field::add(), we don't write unitalized data to
+    disk which would confuse valgrind or MSAN.
+  */
+  virtual void mark_unused_memory_as_defined() {}
+#else
+  void mark_unused_memory_as_defined() {}
+#endif
+
+  virtual double val_real()=0;
+  virtual longlong val_int()=0;
+  /*
+    Get ulonglong representation.
+    Negative values are truncated to 0.
+  */
+  virtual ulonglong val_uint(void)
+  {
+    longlong nr= val_int();
+    return nr < 0 ? 0 : (ulonglong) nr;
+  }
+  virtual bool val_bool()= 0;
+  virtual my_decimal *val_decimal(my_decimal *)=0;
+  inline String *val_str(String *str) { return val_str(str, str); }
+  /*
+     val_str(buf1, buf2) gets two buffers and should use them as follows:
+     if it needs a temp buffer to convert result to string - use buf1
+       example Field_tiny::val_str()
+     if the value exists as a string already - use buf2
+       example Field_string::val_str()
+     consequently, buf2 may be created as 'String buf;' - no memory
+     will be allocated for it. buf1 will be allocated to hold a
+     value if it's too small. Using allocated buffer for buf2 may result in
+     an unnecessary free (and later, may be an alloc).
+     This trickery is used to decrease a number of malloc calls.
+  */
+  virtual String *val_str(String*,String *)=0;
+  virtual bool val_native(Native *to)
+  {
+    DBUG_ASSERT(!is_null());
+    return to->copy((const char *) ptr, pack_length());
+  }
+  String *val_int_as_str(String *val_buffer, bool unsigned_flag);
+  /*
+    Return the field value as a LEX_CSTRING, without padding to full length
+    (MODE_PAD_CHAR_TO_FULL_LENGTH is temporarily suppressed during the call).
+
+    In case of an empty value, to[0] is assigned to empty_clex_string,
+    memory is not allocated.
+    In case of a non-empty value, the memory is allocated on mem_root.
+    In case of a memory allocation failure, to[0] is assigned to {NULL,0}.
+
+    @param  [IN] mem_root  store non-empty values here
+    @param  [OUT to        return the string here
+    @retval                false (success)
+    @retval                true  (EOM)
+  */
+  bool val_str_nopad(MEM_ROOT *mem_root, LEX_CSTRING *to);
+  fast_field_copier get_fast_field_copier(const Field *from);
+  /*
+   str_needs_quotes() returns TRUE if the value returned by val_str() needs
+   to be quoted when used in constructing an SQL query.
+  */
+  virtual bool str_needs_quotes() const { return false; }
+  const Type_handler *type_handler_for_comparison() const
+  {
+    return type_handler()->type_handler_for_comparison();
+  }
+  Item_result result_type () const
+  {
+    return type_handler()->result_type();
+  }
+  Item_result cmp_type () const
+  {
+    return type_handler()->cmp_type();
+  }
+  virtual bool eq(Field *field)
+  {
+    return (ptr == field->ptr && null_ptr == field->null_ptr &&
+            null_bit == field->null_bit && field->type() == type());
+  }
+  virtual bool eq_def(const Field *field) const;
+  
+  /*
+    pack_length() returns size (in bytes) used to store field data in memory
+    (i.e. it returns the maximum size of the field in a row of the table,
+    which is located in RAM).
+  */
+  virtual uint32 pack_length() const { return (uint32) field_length; }
+
+  /*
+    pack_length_in_rec() returns size (in bytes) used to store field data on
+    storage (i.e. it returns the maximal size of the field in a row of the
+    table, which is located on disk).
+  */
+  virtual uint32 pack_length_in_rec() const { return pack_length(); }
+  virtual bool compatible_field_size(uint metadata, const Relay_log_info *rli,
+                                     uint16 mflags, int *order) const;
+  virtual uint pack_length_from_metadata(uint field_metadata) const
+  {
+    DBUG_ENTER("Field::pack_length_from_metadata");
+    DBUG_RETURN(field_metadata);
+  }
+  virtual uint row_pack_length() const { return 0; }
+
+  /*
+    data_length() return the "real size" of the data in memory.
+  */
+  virtual uint32 data_length() { return pack_length(); }
+  virtual uint32 sort_length() const { return pack_length(); }
+
+  /*
+    sort_suffix_length() return the length bytes needed to store the length
+    for binary charset
+  */
+  virtual uint32 sort_suffix_length() const { return 0; }
+
+  /* 
+    Get the number bytes occupied by the value in the field.
+    CHAR values are stripped of trailing spaces.
+    Flexible values are stripped of their length.
+  */
+  virtual uint32 value_length()
+  {
+    uint len;
+    if (!zero_pack() &&
+	(type() == MYSQL_TYPE_STRING &&
+        (len= pack_length()) >= 4 && len < 256))
+    {
+      uchar *str, *end;
+      for (str= ptr, end= str+len; end > str && end[-1] == ' '; end--) {}
+      len=(uint) (end-str); 
+      return len;
+    } 
+    return data_length();
+  }
+
+  /**
+     Get the maximum size of the data in packed format.
+
+     @return Maximum data length of the field when packed using the
+     Field::pack() function.
+   */
+  virtual uint32 max_data_length() const {
+    return pack_length();
+  };
+
+  virtual int reset() { bzero(ptr,pack_length()); return 0; }
+  virtual void reset_fields() {}
+  const uchar *ptr_in_record(const uchar *record) const
+  {
+    my_ptrdiff_t l_offset= (my_ptrdiff_t) (ptr -  table->record[0]);
+    DBUG_ASSERT(l_offset >= 0 && table->s->rec_buff_length - l_offset > 0);
+    return record + l_offset;
+  }
+  virtual int set_default();
+
+  bool has_update_default_function() const
+  {
+    return flags & ON_UPDATE_NOW_FLAG;
+  }
+  bool has_default_now_unireg_check() const
+  {
+    return unireg_check == TIMESTAMP_DN_FIELD
+        || unireg_check == TIMESTAMP_DNUN_FIELD;
+  }
+
+  /*
+    Mark the field as having a value supplied by the client, thus it should
+    not be auto-updated.
+  */
+  void set_has_explicit_value()
+  {
+    bitmap_set_bit(&table->has_value_set, field_index);
+  }
+  bool has_explicit_value()
+  {
+    return bitmap_is_set(&table->has_value_set, field_index);
+  }
+  void clear_has_explicit_value()
+  {
+    bitmap_clear_bit(&table->has_value_set, field_index);
+  }
+
+  virtual my_time_t get_timestamp(const uchar *pos, ulong *sec_part) const
+  { DBUG_ASSERT(0); return 0; }
+  my_time_t get_timestamp(ulong *sec_part) const
+  {
+    return get_timestamp(ptr, sec_part);
+  }
+
+  virtual bool binary() const { return 1; }
+  virtual bool zero_pack() const { return 1; }
+  virtual enum ha_base_keytype key_type() const { return HA_KEYTYPE_BINARY; }
+  virtual uint16 key_part_flag() const { return 0; }
+  virtual uint16 key_part_length_bytes() const { return 0; }
+  virtual uint32 key_length() const { return pack_length(); }
+  virtual const Type_handler *type_handler() const= 0;
+  virtual enum_field_types type() const
+  {
+    return type_handler()->field_type();
+  }
+  virtual enum_field_types real_type() const
+  {
+    return type_handler()->real_field_type();
+  }
+  virtual enum_field_types binlog_type() const
+  {
+    /*
+      Binlog stores field->type() as type code by default. For example,
+      it puts MYSQL_TYPE_STRING in case of CHAR, VARCHAR, SET and ENUM,
+      with extra data type details put into metadata.
+
+      Binlog behaviour slightly differs between various MySQL and MariaDB
+      versions for the temporal data types TIME, DATETIME and TIMESTAMP.
+
+      MySQL prior to 5.6 uses MYSQL_TYPE_TIME, MYSQL_TYPE_DATETIME 
+      and MYSQL_TYPE_TIMESTAMP type codes in binlog and stores no 
+      additional metadata.
+
+      MariaDB-5.3 implements new versions for TIME, DATATIME, TIMESTAMP
+      with fractional second precision, but uses the old format for the
+      types TIME(0), DATETIME(0), TIMESTAMP(0), and it still stores
+      MYSQL_TYPE_TIME, MYSQL_TYPE_DATETIME and MYSQL_TYPE_TIMESTAMP in binlog,
+      with no additional metadata.
+      So row-based replication between temporal data types of
+      different precision is not possible in MariaDB.
+
+      MySQL-5.6 also implements a new version of TIME, DATETIME, TIMESTAMP
+      which support fractional second precision 0..6, and use the new
+      format even for the types TIME(0), DATETIME(0), TIMESTAMP(0).
+      For these new data types, MySQL-5.6 stores new type codes 
+      MYSQL_TYPE_TIME2, MYSQL_TYPE_DATETIME2, MYSQL_TYPE_TIMESTAMP2 in binlog,
+      with fractional precision 0..6 put into metadata.
+      This makes it in theory possible to do row-based replication between
+      columns of different fractional precision (e.g. from TIME(1) on master
+      to TIME(6) on slave). However, it's not currently fully implemented yet.
+      MySQL-5.6 can only do row-based replication from the old types
+      TIME, DATETIME, TIMESTAMP (represented by MYSQL_TYPE_TIME,
+      MYSQL_TYPE_DATETIME and MYSQL_TYPE_TIMESTAMP type codes in binlog)
+      to the new corresponding types TIME(0), DATETIME(0), TIMESTAMP(0).
+
+      Note: MariaDB starting from the version 10.0 understands the new
+      MySQL-5.6 type codes MYSQL_TYPE_TIME2, MYSQL_TYPE_DATETIME2,
+      MYSQL_TYPE_TIMESTAMP2. When started over MySQL-5.6 tables both on
+      master and on slave, MariaDB-10.0 can also do row-based replication
+      from the old types TIME, DATETIME, TIMESTAMP to the new MySQL-5.6
+      types TIME(0), DATETIME(0), TIMESTAMP(0).
+
+      Note: perhaps binlog should eventually be modified to store
+      real_type() instead of type() for all column types.
+    */
+    return type();
+  }
+  virtual Binlog_type_info binlog_type_info() const
+  {
+    DBUG_ASSERT(Field::type() == binlog_type());
+    return Binlog_type_info(Field::type(), 0, 0);
+  }
+  virtual en_fieldtype tmp_engine_column_type(bool use_packed_rows) const
+  {
+    return FIELD_NORMAL;
+  }
+  /*
+    Conversion type for from the source to the current field.
+  */
+  virtual enum_conv_type rpl_conv_type_from(const Conv_source &source,
+                                            const Relay_log_info *rli,
+                                            const Conv_param &param)
+                                            const= 0;
+  enum_conv_type rpl_conv_type_from_same_data_type(uint16 metadata,
+                                                   const Relay_log_info *rli,
+                                                   const Conv_param &param)
+                                                   const;
+  inline  int cmp(const uchar *str) const { return cmp(ptr,str); }
+  /*
+    The following method is used for comparing prefix keys.
+    Currently it's only used in partitioning.
+  */
+  virtual int cmp_prefix(const uchar *a, const uchar *b,
+                         size_t prefix_len) const
+  { return cmp(a, b); }
+  virtual int cmp(const uchar *,const uchar *) const=0;
+  virtual int cmp_binary(const uchar *a,const uchar *b, uint32 max_length=~0U) const
+  { return memcmp(a,b,pack_length()); }
+  virtual int cmp_offset(my_ptrdiff_t row_offset)
+  { return cmp(ptr,ptr+row_offset); }
+  virtual int cmp_binary_offset(uint row_offset)
+  { return cmp_binary(ptr, ptr+row_offset); };
+  virtual int key_cmp(const uchar *a,const uchar *b) const
+  { return cmp(a, b); }
+  virtual int key_cmp(const uchar *str, uint length) const
+  { return cmp(ptr,str); }
+  /*
+    Update the value m of the 'min_val' field with the current value v
+    of this field if force_update is set to TRUE or if v < m.
+    Return TRUE if the value has been updated.
+  */  
+  virtual bool update_min(Field *min_val, bool force_update)
+  { 
+    bool update_fl= force_update || cmp(ptr, min_val->ptr) < 0;
+    if (update_fl)
+    {
+      min_val->set_notnull();
+      memcpy(min_val->ptr, ptr, pack_length());
+    }
+    return update_fl;
+  }
+  /*
+    Update the value m of the 'max_val' field with the current value v
+    of this field if force_update is set to TRUE or if v > m.
+    Return TRUE if the value has been updated.
+  */  
+  virtual bool update_max(Field *max_val, bool force_update)
+  { 
+    bool update_fl= force_update || cmp(ptr, max_val->ptr) > 0;
+    if (update_fl)
+    {
+      max_val->set_notnull();
+      memcpy(max_val->ptr, ptr, pack_length());
+    }
+    return update_fl;
+  }
+  virtual void store_field_value(uchar *val, uint len)
+  {
+     memcpy(ptr, val, len);
+  }
+  virtual uint decimals() const { return 0; }
+  virtual Information_schema_numeric_attributes
+            information_schema_numeric_attributes() const
+  {
+    return Information_schema_numeric_attributes();
+  }
+  virtual Information_schema_character_attributes
+            information_schema_character_attributes() const
+  {
+    return Information_schema_character_attributes();
+  }
+  virtual void update_data_type_statistics(Data_type_statistics *st) const
+  { }
+  /*
+    Caller beware: sql_type can change str.Ptr, so check
+    ptr() to see if it changed if you are using your own buffer
+    in str and restore it with set() if needed
+  */
+  virtual void sql_type(String &str) const =0;
+  virtual void sql_rpl_type(String *str) const { sql_type(*str); }
+  virtual uint size_of() const =0;		// For new field
+  inline bool is_null(my_ptrdiff_t row_offset= 0) const
+  {
+    /*
+      The table may have been marked as containing only NULL values
+      for all fields if it is a NULL-complemented row of an OUTER JOIN
+      or if the query is an implicitly grouped query (has aggregate
+      functions but no GROUP BY clause) with no qualifying rows. If
+      this is the case (in which TABLE::null_row is true), the field
+      is considered to be NULL.
+
+      Note that if a table->null_row is set then also all null_bits are
+      set for the row.
+
+      In the case of the 'result_field' for GROUP BY, table->null_row might
+      refer to the *next* row in the table (when the algorithm is: read the
+      next row, see if any of group column values have changed, send the
+      result - grouped - row to the client if yes). So, table->null_row might
+      be wrong, but such a result_field is always nullable (that's defined by
+      original_field->maybe_null()) and we trust its null bit.
+    */
+    return null_ptr ? null_ptr[row_offset] & null_bit : table->null_row;
+  }
+  inline bool is_real_null(my_ptrdiff_t row_offset= 0) const
+    { return null_ptr && (null_ptr[row_offset] & null_bit); }
+  inline bool is_null_in_record(const uchar *record) const
+  {
+    if (maybe_null_in_table())
+      return record[(uint) (null_ptr - table->record[0])] & null_bit;
+    return 0;
+  }
+  inline void set_null(my_ptrdiff_t row_offset= 0)
+    { if (null_ptr) null_ptr[row_offset]|= null_bit; }
+  inline void set_notnull(my_ptrdiff_t row_offset= 0)
+    { if (null_ptr) null_ptr[row_offset]&= (uchar) ~null_bit; }
+  inline bool maybe_null(void) const
+  { return null_ptr != 0 || table->maybe_null; }
+  // Set to NULL on LOAD DATA or LOAD XML
+  virtual bool load_data_set_null(THD *thd);
+  // Reset when a LOAD DATA file ended unexpectedly
+  virtual bool load_data_set_no_data(THD *thd, bool fixed_format);
+  void load_data_set_value(const char *pos, uint length, CHARSET_INFO *cs);
+
+  /* @return true if this field is NULL-able (even if temporarily) */
+  inline bool real_maybe_null() const { return null_ptr != 0; }
+  uint null_offset(const uchar *record) const
+  { return (uint) (null_ptr - record); }
+  /*
+    For a NULL-able field (that can actually store a NULL value in a table)
+    null_ptr points to the "null bitmap" in the table->record[0] header. For
+    NOT NULL fields it is either 0 or points outside table->record[0] into the
+    table->triggers->extra_null_bitmap (so that the field can store a NULL
+    value temporarily, only in memory)
+  */
+  bool maybe_null_in_table() const
+  { return null_ptr >= table->record[0] && null_ptr <= ptr; }
+
+  uint null_offset() const
+  { return null_offset(table->record[0]); }
+  void set_null_ptr(uchar *p_null_ptr, uint p_null_bit)
+  {
+    null_ptr= p_null_ptr;
+    null_bit= static_cast<uchar>(p_null_bit);
+  }
+
+  bool stored_in_db() const { return !vcol_info || vcol_info->stored_in_db; }
+  bool check_vcol_sql_mode_dependency(THD *, vcol_init_mode mode) const;
+
+  virtual sql_mode_t value_depends_on_sql_mode() const
+  {
+    return 0;
+  }
+  virtual sql_mode_t conversion_depends_on_sql_mode(THD *thd,
+                                                    Item *expr) const
+  {
+    return (sql_mode_t) 0;
+  }
+  virtual sql_mode_t can_handle_sql_mode_dependency_on_store() const
+  {
+    return 0;
+  }
+
+  inline THD *get_thd() const
+  { return likely(table) ? table->in_use : current_thd; }
+
+  enum {
+    LAST_NULL_BYTE_UNDEF= 0
+  };
+
+  /*
+    Find the position of the last null byte for the field.
+
+    SYNOPSIS
+      last_null_byte()
+
+    DESCRIPTION
+      Return a pointer to the last byte of the null bytes where the
+      field conceptually is placed.
+
+    RETURN VALUE
+      The position of the last null byte relative to the beginning of
+      the record. If the field does not use any bits of the null
+      bytes, the value 0 (LAST_NULL_BYTE_UNDEF) is returned.
+   */
+  size_t last_null_byte() const {
+    size_t bytes= do_last_null_byte();
+    DBUG_PRINT("debug", ("last_null_byte() ==> %ld", (long) bytes));
+    DBUG_ASSERT(bytes <= table->s->null_bytes);
+    return bytes;
+  }
+
+  /*
+    Create mem-comparable sort key part for a sort key
+  */
+  void make_sort_key_part(uchar *buff, uint length);
+
+  /*
+    create a compact sort key which can be compared with a comparison
+    function. They are called packed sort keys
+  */
+  virtual uint make_packed_sort_key_part(uchar *buff,
+                                         const SORT_FIELD_ATTR *sort_field);
+
+  virtual void make_send_field(Send_field *);
+
+  /*
+    Some implementations actually may write up to 8 bytes regardless of what
+    size was requested. This is due to the minimum value of the system variable
+    max_sort_length.
+  */
+
+  virtual void sort_string(uchar *buff,uint length)=0;
+  virtual bool optimize_range(uint idx, uint part) const;
+  virtual void free() {}
+  virtual Field *make_new_field(MEM_ROOT *root, TABLE *new_table,
+                                bool keep_type);
+  virtual Field *new_key_field(MEM_ROOT *root, TABLE *new_table,
+                               uchar *new_ptr, uint32 length,
+                               uchar *new_null_ptr, uint new_null_bit);
+  Field *create_tmp_field(MEM_ROOT *root, TABLE *new_table,
+                          bool maybe_null_arg);
+  Field *create_tmp_field(MEM_ROOT *root, TABLE *new_table)
+  {
+    return create_tmp_field(root, new_table, maybe_null());
+  }
+  Field *clone(MEM_ROOT *mem_root, TABLE *new_table);
+  Field *clone(MEM_ROOT *mem_root, TABLE *new_table, my_ptrdiff_t diff);
+  inline void move_field(uchar *ptr_arg,uchar *null_ptr_arg,uchar null_bit_arg)
+  {
+    ptr=ptr_arg; null_ptr=null_ptr_arg; null_bit=null_bit_arg;
+  }
+  inline void move_field(uchar *ptr_arg) { ptr=ptr_arg; }
+  inline uchar *record_ptr() // record[0] or wherever the field was moved to
+  {
+    my_ptrdiff_t offset= table->s->field[field_index]->ptr - table->s->default_values;
+    return ptr - offset;
+  }
+  virtual void move_field_offset(my_ptrdiff_t ptr_diff)
+  {
+    ptr=ADD_TO_PTR(ptr,ptr_diff, uchar*);
+    if (null_ptr)
+      null_ptr=ADD_TO_PTR(null_ptr,ptr_diff,uchar*);
+  }
+  void get_image(uchar *buff, uint length, CHARSET_INFO *cs) const
+  { get_image(buff, length, ptr, cs); }
+  virtual void get_image(uchar *buff, uint length,
+                         const uchar *ptr_arg, CHARSET_INFO *cs) const
+    { memcpy(buff,ptr_arg,length); }
+  virtual void set_image(const uchar *buff,uint length, CHARSET_INFO *cs)
+    { memcpy(ptr,buff,length); }
+
+
+  /*
+    Copy a field part into an output buffer.
+
+    SYNOPSIS
+      Field::get_key_image()
+      buff   [out] output buffer
+      length       output buffer size
+      type         itMBR for geometry blobs, otherwise itRAW
+
+    DESCRIPTION
+      This function makes a copy of field part of size equal to or
+      less than "length" parameter value.
+      For fields of string types (CHAR, VARCHAR, TEXT) the rest of buffer
+      is padded by zero byte.
+
+    NOTES
+      For variable length character fields (i.e. UTF-8) the "length"
+      parameter means a number of output buffer bytes as if all field
+      characters have maximal possible size (mbmaxlen). In the other words,
+      "length" parameter is a number of characters multiplied by
+      field_charset->mbmaxlen.
+
+    RETURN
+      Number of copied bytes (excluding padded zero bytes -- see above).
+  */
+
+  uint get_key_image(uchar *buff, uint length, imagetype type_arg) const
+  { return get_key_image(buff, length, ptr, type_arg); }
+  virtual uint get_key_image(uchar *buff, uint length, const uchar *ptr_arg, imagetype type_arg) const
+  {
+    get_image(buff, length, ptr_arg, &my_charset_bin);
+    return length;
+  }
+  virtual void set_key_image(const uchar *buff,uint length)
+    { set_image(buff,length, &my_charset_bin); }
+  inline longlong val_int_offset(uint row_offset)
+    {
+      ptr+=row_offset;
+      longlong tmp=val_int();
+      ptr-=row_offset;
+      return tmp;
+    }
+  inline longlong val_int(const uchar *new_ptr)
+  {
+    uchar *old_ptr= ptr;
+    longlong return_value;
+    ptr= (uchar*) new_ptr;
+    return_value= val_int();
+    ptr= old_ptr;
+    return return_value;
+  }
+  inline String *val_str(String *str, const uchar *new_ptr)
+  {
+    uchar *old_ptr= ptr;
+    ptr= (uchar*) new_ptr;
+    val_str(str);
+    ptr= old_ptr;
+    return str;
+  }
+  virtual bool send(Protocol *protocol);
+
+  virtual uchar *pack(uchar *to, const uchar *from, uint max_length);
+  /**
+     @overload Field::pack(uchar*, const uchar*, uint, bool)
+  */
+  uchar *pack(uchar *to, const uchar *from)
+  {
+    DBUG_ENTER("Field::pack");
+    uchar *result= this->pack(to, from, UINT_MAX);
+    DBUG_RETURN(result);
+  }
+
+  virtual const uchar *unpack(uchar* to, const uchar *from,
+                              const uchar *from_end, uint param_data=0);
+
+  virtual uint packed_col_length(const uchar *to, uint length)
+  { return length;}
+  virtual uint max_packed_col_length(uint max_length)
+  { return max_length;}
+  virtual bool is_packable() const { return false; }
+
+  uint offset(const uchar *record) const
+  {
+    return (uint) (ptr - record);
+  }
+  void copy_from_tmp(int offset);
+  uint fill_cache_field(struct st_cache_field *copy);
+  virtual bool get_date(MYSQL_TIME *ltime, date_mode_t fuzzydate);
+  virtual longlong val_datetime_packed(THD *thd);
+  virtual longlong val_time_packed(THD *thd);
+  virtual const TYPELIB *get_typelib() const { return NULL; }
+  virtual CHARSET_INFO *charset() const= 0;
+  virtual const DTCollation &dtcollation() const= 0;
+  virtual CHARSET_INFO *charset_for_protocol(void) const
+  { return binary() ? &my_charset_bin : charset(); }
+  virtual CHARSET_INFO *sort_charset(void) const { return charset(); }
+  virtual bool has_charset(void) const { return FALSE; }
+  virtual int set_time() { return 1; }
+  bool set_warning(Sql_condition::enum_warning_level, unsigned int code,
+                   int cuted_increment, ulong current_row=0) const;
+  virtual void print_key_value(String *out, uint32 length);
+  void print_key_part_value(String *out, const uchar *key, uint32 length);
+  void print_key_value_binary(String *out, const uchar* key, uint32 length);
+protected:
+  bool set_warning(unsigned int code, int cuted_increment) const
+  {
+    return set_warning(Sql_condition::WARN_LEVEL_WARN, code, cuted_increment);
+  }
+  bool set_note(unsigned int code, int cuted_increment) const
+  {
+    return set_warning(Sql_condition::WARN_LEVEL_NOTE, code, cuted_increment);
+  }
+  void set_datetime_warning(Sql_condition::enum_warning_level, uint code,
+                            const ErrConv *str, const char *typestr,
+                            int cuted_increment) const;
+  void set_datetime_warning(uint code,
+                            const ErrConv *str, const char *typestr,
+                            int cuted_increment) const
+  {
+    set_datetime_warning(Sql_condition::WARN_LEVEL_WARN, code, str, typestr,
+                         cuted_increment);
+  }
+  void set_warning_truncated_wrong_value(const char *type, const char *value);
+  inline bool check_overflow(int op_result)
+  {
+    return (op_result == E_DEC_OVERFLOW);
+  }
+  int warn_if_overflow(int op_result);
+  Copy_func *get_identical_copy_func() const;
+  bool can_optimize_scalar_range(const RANGE_OPT_PARAM *param,
+                                 const KEY_PART *key_part,
+                                 const Item_bool_func *cond,
+                                 scalar_comparison_op op,
+                                 const Item *value) const;
+  uchar *make_key_image(MEM_ROOT *mem_root, const KEY_PART *key_part);
+  SEL_ARG *get_mm_leaf_int(RANGE_OPT_PARAM *param, KEY_PART *key_part,
+                           const Item_bool_func *cond,
+                           scalar_comparison_op op, Item *value,
+                           bool unsigned_field);
+  /*
+    Make a leaf tree for the cases when the value was stored
+    to the field exactly, without any truncation, rounding or adjustments.
+    For example, if we stored an INT value into an INT column,
+    and value->save_in_field_no_warnings() returned 0,
+    we know that the value was stored exactly.
+  */
+  SEL_ARG *stored_field_make_mm_leaf_exact(RANGE_OPT_PARAM *param,
+                                           KEY_PART *key_part,
+                                           scalar_comparison_op op,
+                                           Item *value);
+  /*
+    Make a leaf tree for the cases when we don't know if
+    the value was stored to the field without any data loss,
+    or was modified to a smaller or a greater value.
+    Used for the data types whose methods Field::store*()
+    silently adjust the value. This is the most typical case.
+  */
+  SEL_ARG *stored_field_make_mm_leaf(RANGE_OPT_PARAM *param,
+                                     KEY_PART *key_part,
+                                     scalar_comparison_op op, Item *value);
+  /*
+    Make a leaf tree when an INT value was stored into a field of INT type,
+    and some truncation happened. Tries to adjust the range search condition
+    when possible, e.g. "tinytint < 300" -> "tinyint <= 127".
+    Can also return SEL_ARG_IMPOSSIBLE(), and NULL (not sargable).
+  */
+  SEL_ARG *stored_field_make_mm_leaf_bounded_int(RANGE_OPT_PARAM *param,
+                                                 KEY_PART *key_part,
+                                                 scalar_comparison_op op,
+                                                 Item *value,
+                                                 bool unsigned_field);
+  /*
+    Make a leaf tree when some truncation happened during
+    value->save_in_field_no_warning(this), and we cannot yet adjust the range
+    search condition for the current combination of the field and the value
+    data types.
+    Returns SEL_ARG_IMPOSSIBLE() for "=" and "<=>".
+    Returns NULL (not sargable) for other comparison operations.
+  */
+  SEL_ARG *stored_field_make_mm_leaf_truncated(RANGE_OPT_PARAM *prm,
+                                               scalar_comparison_op,
+                                               Item *value);
+public:
+  void set_table_name(String *alias)
+  {
+    table_name= &alias->Ptr;
+  }
+  void init(TABLE *table_arg)
+  {
+    orig_table= table= table_arg;
+    set_table_name(&table_arg->alias);
+  }
+  virtual void init_for_tmp_table(Field *org_field, TABLE *new_table)
+  {
+    init(new_table);
+    orig_table= org_field->orig_table;
+    vcol_info= 0;
+    cond_selectivity= 1.0;
+    next_equal_field= NULL;
+    option_list= NULL;
+    option_struct= NULL;
+    if (org_field->type() == MYSQL_TYPE_VAR_STRING ||
+        org_field->type() == MYSQL_TYPE_VARCHAR)
+      new_table->s->db_create_options|= HA_OPTION_PACK_RECORD;
+  }
+  void init_for_make_new_field(TABLE *new_table_arg, TABLE *orig_table_arg)
+  {
+    init(new_table_arg);
+    /*
+      Normally orig_table is different from table only if field was
+      created via ::make_new_field.  Here we alter the type of field,
+      so ::make_new_field is not applicable. But we still need to
+      preserve the original field metadata for the client-server
+      protocol.
+    */
+    orig_table= orig_table_arg;
+  }
+
+  /* maximum possible display length */
+  virtual uint32 max_display_length() const= 0;
+  /**
+    Whether a field being created has the samle type.
+    Used by the ALTER TABLE
+  */
+  virtual bool is_equal(const Column_definition &new_field) const= 0;
+  // Used as double dispatch pattern: calls virtual method of handler
+  virtual bool
+  can_be_converted_by_engine(const Column_definition &new_type) const
+  {
+    return false;
+  }
+  /* convert decimal to longlong with overflow check */
+  longlong convert_decimal2longlong(const my_decimal *val, bool unsigned_flag,
+                                    int *err);
+  /*
+    Maximum number of bytes in character representation.
+    - For string types it is equal to the field capacity, in bytes.
+    - For non-string types it represents the longest possible string length
+      after conversion to string.
+  */
+  virtual uint32 character_octet_length() const
+  {
+    return field_length;
+  }
+  /* The max. number of characters */
+  virtual uint32 char_length() const
+  {
+    return field_length / charset()->mbmaxlen;
+  }
+
+  ha_storage_media field_storage_type() const
+  {
+    return (ha_storage_media)
+      ((flags >> FIELD_FLAGS_STORAGE_MEDIA) & 3);
+  }
+
+  void set_storage_type(ha_storage_media storage_type_arg)
+  {
+    DBUG_ASSERT(field_storage_type() == HA_SM_DEFAULT);
+    flags |= static_cast<uint32>(storage_type_arg) <<
+      FIELD_FLAGS_STORAGE_MEDIA;
+  }
+
+  column_format_type column_format() const
+  {
+    return (column_format_type)
+      ((flags >> FIELD_FLAGS_COLUMN_FORMAT) & 3);
+  }
+
+  void set_column_format(column_format_type column_format_arg)
+  {
+    DBUG_ASSERT(column_format() == COLUMN_FORMAT_TYPE_DEFAULT);
+    flags |= static_cast<uint32>(column_format_arg) <<
+      FIELD_FLAGS_COLUMN_FORMAT;
+  }
+
+  bool vers_sys_field() const
+  {
+    return flags & (VERS_SYS_START_FLAG | VERS_SYS_END_FLAG);
+  }
+
+  bool vers_update_unversioned() const
+  {
+    return flags & VERS_UPDATE_UNVERSIONED_FLAG;
+  }
+
+  /*
+    Validate a non-null field value stored in the given record
+    according to the current thread settings, e.g. sql_mode.
+    @param thd     - the thread
+    @param record  - the record to check in
+  */
+  virtual bool validate_value_in_record(THD *thd, const uchar *record) const
+  { return false; }
+  bool validate_value_in_record_with_warn(THD *thd, const uchar *record);
+  key_map get_possible_keys();
+
+  /* Hash value */
+  virtual void hash(ulong *nr, ulong *nr2);
+
+  /**
+    Get the upper limit of the MySQL integral and floating-point type.
+
+    @return maximum allowed value for the field
+  */
+  virtual ulonglong get_max_int_value() const
+  {
+    DBUG_ASSERT(false);
+    return 0ULL;
+  }
+
+/**
+  Checks whether a string field is part of write_set.
+
+  @return
+    FALSE  - If field is not char/varchar/....
+           - If field is char/varchar/.. and is not part of write set.
+    TRUE   - If field is char/varchar/.. and is part of write set.
+*/
+  virtual bool is_varchar_and_in_write_set() const { return FALSE; }
+
+  /* Check whether the field can be used as a join attribute in hash join */
+  virtual bool hash_join_is_possible() { return TRUE; }
+  virtual bool eq_cmp_as_binary() { return TRUE; }
+
+  /* Position of the field value within the interval of [min, max] */
+  virtual double pos_in_interval(Field *min, Field *max)
+  {
+    return (double) 0.5; 
+  }
+
+  /*
+    Check if comparison between the field and an item unambiguously
+    identifies a distinct field value.
+
+    Example1: SELECT * FROM t1 WHERE int_column=10;
+              This example returns distinct integer value of 10.
+
+    Example2: SELECT * FROM t1 WHERE varchar_column=DATE'2001-01-01'
+              This example returns non-distinct values.
+              Comparison as DATE will return '2001-01-01' and '2001-01-01x',
+              but these two values are not equal to each other as VARCHARs.
+    See also the function with the same name in sql_select.cc.
+  */
+  virtual bool test_if_equality_guarantees_uniqueness(const Item *const_item)
+                                                      const;
+  virtual bool can_be_substituted_to_equal_item(const Context &ctx,
+                                        const Item_equal *item);
+  virtual Item *get_equal_const_item(THD *thd, const Context &ctx,
+                                     Item *const_item)
+  {
+    return const_item;
+  }
+  virtual bool can_optimize_keypart_ref(const Item_bool_func *cond,
+                                        const Item *item) const;
+  virtual bool can_optimize_hash_join(const Item_bool_func *cond,
+                                      const Item *item) const
+  {
+    return can_optimize_keypart_ref(cond, item);
+  }
+  virtual bool can_optimize_group_min_max(const Item_bool_func *cond,
+                                          const Item *const_item) const;
+  /**
+    Test if Field can use range optimizer for a standard comparison operation:
+      <=, <, =, <=>, >, >=
+    Note, this method does not cover spatial operations.
+  */
+  virtual bool can_optimize_range(const Item_bool_func *cond,
+                                  const Item *item,
+                                  bool is_eq_func) const;
+
+  virtual SEL_ARG *get_mm_leaf(RANGE_OPT_PARAM *param, KEY_PART *key_part,
+                               const Item_bool_func *cond,
+                               scalar_comparison_op op, Item *value)= 0;
+
+  bool can_optimize_outer_join_table_elimination(const Item_bool_func *cond,
+                                                 const Item *item) const
+  {
+    // Exactly the same rules with REF access
+    return can_optimize_keypart_ref(cond, item);
+  }
+
+  bool save_in_field_default_value(bool view_eror_processing);
+  bool save_in_field_ignore_value(bool view_error_processing);
+
+  /* Mark field in read map. Updates also virtual fields */
+  void register_field_in_read_map();
+
+  virtual Compression_method *compression_method() const { return 0; }
+
+  virtual Virtual_tmp_table **virtual_tmp_table_addr()
+  {
+    return NULL;
+  }
+  virtual bool sp_prepare_and_store_item(THD *thd, Item **value);
+
+  friend int cre_myisam(char * name, TABLE *form, uint options,
+			ulonglong auto_increment_value);
+  friend class Copy_field;
+  friend class Item_avg_field;
+  friend class Item_std_field;
+  friend class Item_sum_num;
+  friend class Item_sum_sum;
+  friend class Item_sum_count;
+  friend class Item_sum_avg;
+  friend class Item_sum_std;
+  friend class Item_sum_min;
+  friend class Item_sum_max;
+  friend class Item_func_group_concat;
+
+private:
+  /*
+    Primitive for implementing last_null_byte().
+
+    SYNOPSIS
+      do_last_null_byte()
+
+    DESCRIPTION
+      Primitive for the implementation of the last_null_byte()
+      function. This represents the inheritance interface and can be
+      overridden by subclasses.
+   */
+  virtual size_t do_last_null_byte() const;
+
+protected:
+  uchar *pack_int(uchar *to, const uchar *from, size_t size)
+  {
+    memcpy(to, from, size);
+    return to + size;
+  }
+
+  const uchar *unpack_int(uchar* to, const uchar *from,
+                          const uchar *from_end, size_t size)
+  {
+    if (from + size > from_end)
+      return 0;
+    memcpy(to, from, size);
+    return from + size;
+  }
+
+  uchar *pack_int16(uchar *to, const uchar *from)
+  { return pack_int(to, from, 2); }
+  const uchar *unpack_int16(uchar* to, const uchar *from, const uchar *from_end)
+  { return unpack_int(to, from, from_end, 2); }
+  uchar *pack_int24(uchar *to, const uchar *from)
+  { return pack_int(to, from, 3); }
+  const uchar *unpack_int24(uchar* to, const uchar *from, const uchar *from_end)
+  { return unpack_int(to, from, from_end, 3); }
+  uchar *pack_int32(uchar *to, const uchar *from)
+  { return pack_int(to, from, 4); }
+  const uchar *unpack_int32(uchar* to, const uchar *from, const uchar *from_end)
+  { return unpack_int(to, from, from_end, 4); }
+  uchar *pack_int64(uchar* to, const uchar *from)
+  { return pack_int(to, from, 8); }
+  const uchar *unpack_int64(uchar* to, const uchar *from,  const uchar *from_end)
+  { return unpack_int(to, from, from_end, 8); }
+
+  double pos_in_interval_val_real(Field *min, Field *max);
+  double pos_in_interval_val_str(Field *min, Field *max, uint data_offset);
+};
+
+
+class Field_num :public Field {
+protected:
+  int check_edom_and_important_data_truncation(const char *type, bool edom,
+                                               CHARSET_INFO *cs,
+                                               const char *str, size_t length,
+                                               const char *end_of_num);
+  int check_edom_and_truncation(const char *type, bool edom,
+                                CHARSET_INFO *cs,
+                                const char *str, size_t length,
+                                const char *end_of_num);
+  int check_int(CHARSET_INFO *cs, const char *str, size_t length,
+                const char *int_end, int error)
+  {
+    return check_edom_and_truncation("integer",
+                                     error == MY_ERRNO_EDOM || str == int_end,
+                                     cs, str, length, int_end);
+  }
+  bool get_int(CHARSET_INFO *cs, const char *from, size_t len,
+               longlong *rnd, ulonglong unsigned_max,
+               longlong signed_min, longlong signed_max);
+  void prepend_zeros(String *value) const;
+  Item *get_equal_zerofill_const_item(THD *thd, const Context &ctx,
+                                      Item *const_item);
+  Binlog_type_info::binlog_sign_t binlog_signedness() const
+  {
+    return (flags & UNSIGNED_FLAG) ? Binlog_type_info::SIGN_UNSIGNED :
+                                     Binlog_type_info::SIGN_SIGNED;
+  }
+  bool send_numeric_zerofill_str(Protocol_text *protocol,
+                                 protocol_send_type_t send_type);
+
+public:
+  const uint8 dec;
+  bool zerofill,unsigned_flag;	// Purify cannot handle bit fields
+  Field_num(uchar *ptr_arg,uint32 len_arg, uchar *null_ptr_arg,
+	    uchar null_bit_arg, utype unireg_check_arg,
+	    const LEX_CSTRING *field_name_arg,
+            uint8 dec_arg, bool zero_arg, bool unsigned_arg);
+  CHARSET_INFO *charset() const override
+  {
+    return DTCollation_numeric::singleton().collation;
+  }
+  const DTCollation &dtcollation() const override
+  {
+    return DTCollation_numeric::singleton();
+  }
+  sql_mode_t can_handle_sql_mode_dependency_on_store() const override;
+  Item *get_equal_const_item(THD *thd, const Context &ctx, Item *const_item)
+    override
+  {
+    return (flags & ZEROFILL_FLAG) ?
+           get_equal_zerofill_const_item(thd, ctx, const_item) :
+           const_item;
+  }
+  void add_zerofill_and_unsigned(String &res) const;
+  friend class Create_field;
+  void make_send_field(Send_field *) override;
+  uint decimals() const override { return (uint) dec; }
+  uint size_of() const override { return sizeof(*this); }
+  bool eq_def(const Field *field) const override;
+  Copy_func *get_copy_func(const Field *from) const override
+  {
+    if (unsigned_flag && from->cmp_type() == DECIMAL_RESULT)
+      return do_field_decimal;
+    return do_field_int;
+  }
+  int save_in_field(Field *to) override
+  {
+    return to->store(val_int(), MY_TEST(flags & UNSIGNED_FLAG));
+  }
+  bool is_equal(const Column_definition &new_field) const override;
+  uint row_pack_length() const override { return pack_length(); }
+  uint32 pack_length_from_metadata(uint field_metadata) const override
+  {
+    uint32 length= pack_length();
+    DBUG_PRINT("result", ("pack_length_from_metadata(%d): %u",
+                          field_metadata, length));
+    return length;
+  }
+  double pos_in_interval(Field *min, Field *max) override
+  {
+    return pos_in_interval_val_real(min, max);
+  }
+  SEL_ARG *get_mm_leaf(RANGE_OPT_PARAM *param, KEY_PART *key_part,
+                       const Item_bool_func *cond,
+                       scalar_comparison_op op, Item *value) override;
+  Binlog_type_info binlog_type_info() const override
+  {
+    DBUG_ASSERT(Field_num::type() == binlog_type());
+    return Binlog_type_info(Field_num::type(), 0, 0, binlog_signedness());
+  }
+};
+
+
+class Field_str :public Field {
+protected:
+  DTCollation m_collation;
+  // A short alias for m_collation.collation with non-virtual linkage
+  const CHARSET_INFO *field_charset() const { return m_collation.collation; }
+  uint mbmaxlen() const { return m_collation.collation->mbmaxlen; }
+public:
+  bool can_be_substituted_to_equal_item(const Context &ctx,
+                                        const Item_equal *item_equal) override;
+  Field_str(uchar *ptr_arg,uint32 len_arg, uchar *null_ptr_arg,
+	    uchar null_bit_arg, utype unireg_check_arg,
+	    const LEX_CSTRING *field_name_arg,
+	    const DTCollation &collation);
+  uint decimals() const override { return is_created_from_null_item ? 0 : NOT_FIXED_DEC; }
+  int  save_in_field(Field *to) override { return save_in_field_str(to); }
+  bool memcpy_field_possible(const Field *from) const override
+  {
+    return real_type() == from->real_type() &&
+           pack_length() == from->pack_length() &&
+           charset() == from->charset();
+  }
+  int  store(double nr) override;
+  int  store(longlong nr, bool unsigned_val) override;
+  int  store_decimal(const my_decimal *) override;
+  int  store(const char *to,size_t length,CHARSET_INFO *cs) override=0;
+  int  store_hex_hybrid(const char *str, size_t length) override
+  {
+    return store(str, length, &my_charset_bin);
+  }
+  CHARSET_INFO *charset() const override { return m_collation.collation; }
+  const DTCollation &dtcollation() const override
+  {
+    return m_collation;
+  }
+  bool binary() const override { return field_charset() == &my_charset_bin; }
+  uint32 max_display_length() const override { return field_length; }
+  uint32 character_octet_length() const override { return field_length; }
+  uint32 char_length() const override
+  {
+    return field_length / mbmaxlen();
+  }
+  Information_schema_character_attributes
+    information_schema_character_attributes() const override
+  {
+    return Information_schema_character_attributes(max_display_length(),
+                                                   char_length());
+  }
+  friend class Create_field;
+  my_decimal *val_decimal(my_decimal *) override;
+  bool val_bool() override { return val_real() != 0e0; }
+  bool str_needs_quotes() const override { return true; }
+  bool eq_cmp_as_binary() override { return MY_TEST(flags & BINARY_FLAG); }
+  virtual uint length_size() const { return 0; }
+  double pos_in_interval(Field *min, Field *max) override
+  {
+    return pos_in_interval_val_str(min, max, length_size());
+  }
+  bool test_if_equality_guarantees_uniqueness(const Item *const_item) const
+    override;
+  SEL_ARG *get_mm_leaf(RANGE_OPT_PARAM *param, KEY_PART *key_part,
+                       const Item_bool_func *cond,
+                       scalar_comparison_op op, Item *value) override;
+  Binlog_type_info binlog_type_info() const override
+  {
+    DBUG_ASSERT(Field_str::type() == binlog_type());
+    return Binlog_type_info(Field_str::type(), 0, 0, charset());
+  }
+};
+
+/* base class for Field_string, Field_varstring and Field_blob */
+
+class Field_longstr :public Field_str
+{
+protected:
+  int report_if_important_data(const char *ptr, const char *end,
+                               bool count_spaces);
+  bool check_string_copy_error(const String_copier *copier,
+                               const char *end, CHARSET_INFO *cs);
+  int check_conversion_status(const String_copier *copier,
+                              const char *end, CHARSET_INFO *cs,
+                              bool count_spaces)
+  {
+    if (check_string_copy_error(copier, end, cs))
+      return 2;
+    return report_if_important_data(copier->source_end_pos(),
+                                    end, count_spaces);
+  }
+  int well_formed_copy_with_check(char *to, size_t to_length,
+                                  CHARSET_INFO *from_cs,
+                                  const char *from, size_t from_length,
+                                  size_t nchars, bool count_spaces,
+                                  uint *copy_length)
+  {
+    String_copier copier;
+
+    *copy_length= copier.well_formed_copy(field_charset(), to, to_length,
+                                          from_cs, from, from_length,
+                                          nchars);
+
+    return check_conversion_status(&copier, from + from_length, from_cs, count_spaces);
+  }
+  bool cmp_to_string_with_same_collation(const Item_bool_func *cond,
+                                         const Item *item) const;
+  bool cmp_to_string_with_stricter_collation(const Item_bool_func *cond,
+                                             const Item *item) const;
+  int compress(char *to, uint to_length,
+               const char *from, uint length,
+               uint max_length,
+               uint *out_length,
+               CHARSET_INFO *cs, size_t nchars);
+  String *uncompress(String *val_buffer, String *val_ptr,
+                     const uchar *from, uint from_length) const;
+public:
+  Field_longstr(uchar *ptr_arg, uint32 len_arg, uchar *null_ptr_arg,
+                uchar null_bit_arg, utype unireg_check_arg,
+                const LEX_CSTRING *field_name_arg,
+                const DTCollation &collation)
+    :Field_str(ptr_arg, len_arg, null_ptr_arg, null_bit_arg, unireg_check_arg,
+               field_name_arg, collation)
+    {}
+  enum_conv_type rpl_conv_type_from(const Conv_source &source,
+                                    const Relay_log_info *rli,
+                                    const Conv_param &param) const override;
+  int store_decimal(const my_decimal *d) override;
+  uint32 max_data_length() const override;
+  void make_send_field(Send_field *) override;
+  bool send(Protocol *protocol) override;
+
+  bool is_varchar_and_in_write_set() const override
+  {
+    DBUG_ASSERT(table && table->write_set);
+    return bitmap_is_set(table->write_set, field_index);
+  }
+  bool match_collation_to_optimize_range() const { return true; }
+
+  bool can_optimize_keypart_ref(const Item_bool_func *cond,
+                                const Item *item) const override;
+  bool can_optimize_hash_join(const Item_bool_func *cond,
+                              const Item *item) const override;
+  bool can_optimize_group_min_max(const Item_bool_func *cond,
+                                  const Item *const_item) const override;
+  bool can_optimize_range(const Item_bool_func *cond,
+                          const Item *item,
+                          bool is_eq_func) const override;
+  bool is_packable() const override { return true; }
+  uint make_packed_sort_key_part(uchar *buff,
+                                 const SORT_FIELD_ATTR *sort_field)override;
+  uchar* pack_sort_string(uchar *to, const SORT_FIELD_ATTR *sort_field);
+};
+
+/* base class for float and double and decimal (old one) */
+class Field_real :public Field_num {
+protected:
+  double get_double(const char *str, size_t length, CHARSET_INFO *cs, int *err);
+public:
+  bool not_fixed;
+
+  Field_real(uchar *ptr_arg, uint32 len_arg, uchar *null_ptr_arg,
+             uchar null_bit_arg, utype unireg_check_arg,
+             const LEX_CSTRING *field_name_arg,
+             uint8 dec_arg, bool zero_arg, bool unsigned_arg)
+    :Field_num(ptr_arg, len_arg, null_ptr_arg, null_bit_arg, unireg_check_arg,
+               field_name_arg, dec_arg, zero_arg, unsigned_arg),
+    not_fixed(dec_arg >= FLOATING_POINT_DECIMALS)
+    {}
+  Copy_func *get_copy_func(const Field *from) const override
+  {
+    return do_field_real;
+  }
+  enum_conv_type rpl_conv_type_from(const Conv_source &source,
+                                    const Relay_log_info *rli,
+                                    const Conv_param &param) const override;
+  Information_schema_numeric_attributes
+    information_schema_numeric_attributes() const override
+  {
+    return dec == NOT_FIXED_DEC ?
+                  Information_schema_numeric_attributes(field_length) :
+                  Information_schema_numeric_attributes(field_length, dec);
+  }
+  void sql_type(String &str) const override;
+  int save_in_field(Field *to) override { return to->store(val_real()); }
+  bool memcpy_field_possible(const Field *from) const override
+  {
+    /*
+      Cannot do memcpy from a longer field to a shorter field,
+      e.g. a DOUBLE(53,10) into a DOUBLE(10,10).
+      But it should be OK the other way around.
+    */
+    return real_type() == from->real_type() &&
+           pack_length() == from->pack_length() &&
+           is_unsigned() <= from->is_unsigned() &&
+           decimals() == from->decimals() &&
+           field_length >= from->field_length;
+  }
+  int store_decimal(const my_decimal *dec) override
+  { return store(dec->to_double()); }
+  int  store_time_dec(const MYSQL_TIME *ltime, uint dec) override;
+  bool get_date(MYSQL_TIME *ltime, date_mode_t fuzzydate) override;
+  my_decimal *val_decimal(my_decimal *) override;
+  bool val_bool() override { return val_real() != 0e0; }
+  uint32 max_display_length() const override { return field_length; }
+  uint size_of() const override { return sizeof *this; }
+  Item *get_equal_const_item(THD *thd, const Context &ctx, Item *const_item)
+    override;
+};
+
+
+class Field_decimal final  :public Field_real {
+public:
+  Field_decimal(uchar *ptr_arg, uint32 len_arg, uchar *null_ptr_arg,
+		uchar null_bit_arg,
+		enum utype unireg_check_arg, const LEX_CSTRING *field_name_arg,
+		uint8 dec_arg,bool zero_arg,bool unsigned_arg)
+    :Field_real(ptr_arg, len_arg, null_ptr_arg, null_bit_arg,
+                unireg_check_arg, field_name_arg,
+                dec_arg, zero_arg, unsigned_arg)
+    {}
+  Field *make_new_field(MEM_ROOT *root, TABLE *new_table, bool keep_type)
+    override;
+  const Type_handler *type_handler() const override
+  { return &type_handler_olddecimal; }
+  enum ha_base_keytype key_type() const override
+  { return zerofill ? HA_KEYTYPE_BINARY : HA_KEYTYPE_NUM; }
+  Information_schema_numeric_attributes
+    information_schema_numeric_attributes() const override
+  {
+    uint tmp= dec ? 2 : 1; // The sign and the decimal point
+    return Information_schema_numeric_attributes(field_length - tmp, dec);
+  }
+  Copy_func *get_copy_func(const Field *from) const override
+  {
+    return eq_def(from) ? get_identical_copy_func() : do_field_string;
+  }
+  int reset() override;
+  int store(const char *to,size_t length,CHARSET_INFO *charset) override;
+  int store(double nr) override;
+  int store(longlong nr, bool unsigned_val) override;
+  double val_real() override;
+  longlong val_int() override;
+  String *val_str(String *, String *) override;
+  int cmp(const uchar *,const uchar *) const override;
+  void sort_string(uchar *buff,uint length) override;
+  void overflow(bool negative);
+  bool zero_pack() const override { return false; }
+  void sql_type(String &str) const override;
+  uchar *pack(uchar* to, const uchar *from, uint max_length) override
+  {
+    return Field::pack(to, from, max_length);
+  }
+};
+
+
+/* New decimal/numeric field which use fixed point arithmetic */
+class Field_new_decimal final :public Field_num {
+public:
+  /* The maximum number of decimal digits can be stored */
+  uint precision;
+  uint bin_size;
+  /*
+    Constructors take max_length of the field as a parameter - not the
+    precision as the number of decimal digits allowed.
+    So for example we need to count length from precision handling
+    CREATE TABLE ( DECIMAL(x,y)) 
+  */
+  Field_new_decimal(uchar *ptr_arg, uint32 len_arg, uchar *null_ptr_arg,
+                    uchar null_bit_arg,
+                    enum utype unireg_check_arg,
+                    const LEX_CSTRING *field_name_arg,
+                    uint8 dec_arg, bool zero_arg, bool unsigned_arg);
+  const Type_handler *type_handler() const override
+  { return &type_handler_newdecimal; }
+  enum ha_base_keytype key_type() const override { return HA_KEYTYPE_BINARY; }
+  Copy_func *get_copy_func(const Field *from) const override
+  {
+    //  if (from->real_type() == MYSQL_TYPE_BIT) // QQ: why?
+    //    return do_field_int;
+    return do_field_decimal;
+  }
+  int save_in_field(Field *to) override
+  {
+    my_decimal tmp(ptr, precision, dec);
+    return to->store_decimal(&tmp);
+  }
+  bool memcpy_field_possible(const Field *from) const override
+  {
+    return real_type() == from->real_type() &&
+           pack_length() == from->pack_length() &&
+           is_unsigned() <= from->is_unsigned() &&
+           decimals() == from->decimals() &&
+           field_length == from->field_length;
+  }
+  enum_conv_type rpl_conv_type_from(const Conv_source &source,
+                                    const Relay_log_info *rli,
+                                    const Conv_param &param) const override;
+  int  reset() override;
+  bool store_value(const my_decimal *decimal_value);
+  bool store_value(const my_decimal *decimal_value, int *native_error);
+  void set_value_on_overflow(my_decimal *decimal_value, bool sign);
+  int  store(const char *to, size_t length, CHARSET_INFO *charset) override;
+  int  store(double nr) override;
+  int  store(longlong nr, bool unsigned_val) override;
+  int  store_time_dec(const MYSQL_TIME *ltime, uint dec) override;
+  int  store_decimal(const my_decimal *) override;
+  double val_real() override
+  {
+    return my_decimal(ptr, precision, dec).to_double();
+  }
+  longlong val_int() override
+  {
+    return my_decimal(ptr, precision, dec).to_longlong(unsigned_flag);
+  }
+  ulonglong val_uint() override
+  {
+    return (ulonglong) my_decimal(ptr, precision, dec).to_longlong(true);
+  }
+  my_decimal *val_decimal(my_decimal *) override;
+  String *val_str(String *val_buffer, String *) override
+  {
+    uint fixed_precision= zerofill ? precision : 0;
+    return my_decimal(ptr, precision, dec).
+             to_string(val_buffer, fixed_precision, dec, '0');
+  }
+  bool get_date(MYSQL_TIME *ltime, date_mode_t fuzzydate) override
+  {
+    my_decimal nr(ptr, precision, dec);
+    return decimal_to_datetime_with_warn(get_thd(), &nr, ltime,
+                                         fuzzydate, table->s, field_name.str);
+  }
+  bool val_bool() override
+  {
+    return my_decimal(ptr, precision, dec).to_bool();
+  }
+  int cmp(const uchar *, const uchar *) const override;
+  void sort_string(uchar *buff, uint length) override;
+  bool zero_pack() const override { return false; }
+  void sql_type(String &str) const override;
+  uint32 max_display_length() const override { return field_length; }
+  Information_schema_numeric_attributes
+    information_schema_numeric_attributes() const override
+  {
+    return Information_schema_numeric_attributes(precision, dec);
+  }
+  uint size_of() const override { return sizeof *this; }
+  uint32 pack_length() const override { return (uint32) bin_size; }
+  uint pack_length_from_metadata(uint field_metadata) const override;
+  uint row_pack_length() const override { return pack_length(); }
+  bool compatible_field_size(uint field_metadata, const Relay_log_info *rli,
+                             uint16 mflags, int *order_var) const override;
+  bool is_equal(const Column_definition &new_field) const override;
+  const uchar *unpack(uchar* to, const uchar *from, const uchar *from_end,
+                      uint param_data) override;
+  Item *get_equal_const_item(THD *thd, const Context &ctx, Item *const_item)
+    override;
+  Binlog_type_info binlog_type_info() const override;
+};
+
+
+class Field_int :public Field_num
+{
+protected:
+  String *val_str_from_long(String *val_buffer, uint max_char_length,
+                            int radix, long nr);
+public:
+  Field_int(uchar *ptr_arg, uint32 len_arg, uchar *null_ptr_arg,
+            uchar null_bit_arg, enum utype unireg_check_arg,
+            const LEX_CSTRING *field_name_arg, bool zero_arg, bool unsigned_arg)
+    :Field_num(ptr_arg, len_arg, null_ptr_arg, null_bit_arg,
+               unireg_check_arg, field_name_arg, 0, zero_arg, unsigned_arg)
+    {}
+  enum_conv_type rpl_conv_type_from(const Conv_source &source,
+                                    const Relay_log_info *rli,
+                                    const Conv_param &param) const override;
+  bool memcpy_field_possible(const Field *from) const override
+  {
+    return real_type() == from->real_type() &&
+           pack_length() == from->pack_length() &&
+           is_unsigned() == from->is_unsigned();
+  }
+  int store_decimal(const my_decimal *) override;
+  my_decimal *val_decimal(my_decimal *) override;
+  bool val_bool() override { return val_int() != 0; }
+  ulonglong val_uint() override
+  {
+    longlong nr= val_int();
+    return nr < 0 && !unsigned_flag ? 0 : (ulonglong) nr;
+  }
+  int  store_time_dec(const MYSQL_TIME *ltime, uint dec) override;
+  bool get_date(MYSQL_TIME *ltime, date_mode_t fuzzydate) override;
+  virtual const Type_limits_int *type_limits_int() const= 0;
+  uint32 max_display_length() const override
+  {
+    return type_limits_int()->char_length();
+  }
+  Type_numeric_attributes type_numeric_attributes() const override
+  {
+    /*
+      For integer data types, the user-specified length does not constrain the
+      supported range, so e.g. a column of the INT(1) data type supports the
+      full integer range anyway.
+      Choose the maximum from the user-specified length and the maximum
+      possible length determined by the data type capacity:
+        INT(1)  -> 11
+        INT(10) -> 11
+        INT(40) -> 40
+    */
+    uint32 length1= max_display_length();
+    uint32 length2= field_length;
+    return Type_numeric_attributes(MY_MAX(length1, length2),
+                                   decimals(), is_unsigned());
+  }
+  Information_schema_numeric_attributes
+    information_schema_numeric_attributes() const override
+  {
+    uint32 prec= type_limits_int()->precision();
+    return Information_schema_numeric_attributes(prec, 0);
+  }
+  void sql_type(String &str) const override;
+  SEL_ARG *get_mm_leaf(RANGE_OPT_PARAM *param, KEY_PART *key_part,
+                       const Item_bool_func *cond,
+                       scalar_comparison_op op, Item *value) override
+  {
+    return get_mm_leaf_int(param, key_part, cond, op, value, unsigned_flag);
+  }
+};
+
+
+class Field_tiny :public Field_int
+{
+  const Type_handler_general_purpose_int *type_handler_priv() const
+  {
+    if (is_unsigned())
+      return &type_handler_utiny;
+    return &type_handler_stiny;
+  }
+public:
+  Field_tiny(uchar *ptr_arg, uint32 len_arg, uchar *null_ptr_arg,
+	     uchar null_bit_arg,
+	     enum utype unireg_check_arg, const LEX_CSTRING *field_name_arg,
+	     bool zero_arg, bool unsigned_arg)
+    :Field_int(ptr_arg, len_arg, null_ptr_arg, null_bit_arg,
+               unireg_check_arg, field_name_arg, zero_arg, unsigned_arg)
+    {}
+  const Type_handler *type_handler() const override
+    { return type_handler_priv(); }
+  enum ha_base_keytype key_type() const override
+    { return unsigned_flag ? HA_KEYTYPE_BINARY : HA_KEYTYPE_INT8; }
+  int store(const char *to,size_t length,CHARSET_INFO *charset) override;
+  int store(double nr) override;
+  int store(longlong nr, bool unsigned_val) override;
+  int reset() override { ptr[0]=0; return 0; }
+  double val_real() override;
+  longlong val_int() override;
+  String *val_str(String *, String *) override;
+  bool send(Protocol *protocol) override;
+  int cmp(const uchar *,const uchar *) const override;
+  void sort_string(uchar *buff,uint length) override;
+  uint32 pack_length() const override { return 1; }
+  const Type_limits_int *type_limits_int() const override
+  {
+    return type_handler_priv()->type_limits_int();
+  }
+
+  uchar *pack(uchar* to, const uchar *from, uint max_length) override
+  {
+    *to= *from;
+    return to + 1;
+  }
+
+  const uchar *unpack(uchar* to, const uchar *from,
+		      const uchar *from_end, uint param_data) override
+  {
+    if (from == from_end)
+      return 0;
+    *to= *from;
+    return from + 1;
+  }
+  ulonglong get_max_int_value() const override
+  {
+    return unsigned_flag ? 0xFFULL : 0x7FULL;
+  }
+};
+
+
+class Field_short final :public Field_int
+{
+  const Type_handler_general_purpose_int *type_handler_priv() const
+  {
+    if (is_unsigned())
+      return &type_handler_ushort;
+    return &type_handler_sshort;
+  }
+public:
+  Field_short(uchar *ptr_arg, uint32 len_arg, uchar *null_ptr_arg,
+	      uchar null_bit_arg,
+	      enum utype unireg_check_arg, const LEX_CSTRING *field_name_arg,
+	      bool zero_arg, bool unsigned_arg)
+    :Field_int(ptr_arg, len_arg, null_ptr_arg, null_bit_arg,
+               unireg_check_arg, field_name_arg, zero_arg, unsigned_arg)
+    {}
+  Field_short(uint32 len_arg,bool maybe_null_arg,
+              const LEX_CSTRING *field_name_arg,
+	      bool unsigned_arg)
+    :Field_int((uchar*) 0, len_arg, maybe_null_arg ? (uchar*) "": 0,0,
+               NONE, field_name_arg, 0, unsigned_arg)
+    {}
+  const Type_handler *type_handler() const override
+  { return type_handler_priv(); }
+  enum ha_base_keytype key_type() const override
+    { return unsigned_flag ? HA_KEYTYPE_USHORT_INT : HA_KEYTYPE_SHORT_INT;}
+  int store(const char *to,size_t length,CHARSET_INFO *charset) override;
+  int store(double nr) override;
+  int store(longlong nr, bool unsigned_val) override;
+  int reset() override { ptr[0]=ptr[1]=0; return 0; }
+  double val_real() override;
+  longlong val_int() override;
+  String *val_str(String *, String *) override;
+  bool send(Protocol *protocol) override;
+  int cmp(const uchar *,const uchar *) const override;
+  void sort_string(uchar *buff,uint length) override;
+  uint32 pack_length() const override { return 2; }
+  const Type_limits_int *type_limits_int() const override
+  {
+    return type_handler_priv()->type_limits_int();
+  }
+  uchar *pack(uchar* to, const uchar *from, uint) override
+  { return pack_int16(to, from); }
+
+  const uchar *unpack(uchar* to, const uchar *from,
+                      const uchar *from_end, uint) override
+  { return unpack_int16(to, from, from_end); }
+  ulonglong get_max_int_value() const override
+  {
+    return unsigned_flag ? 0xFFFFULL : 0x7FFFULL;
+  }
+};
+
+class Field_medium final :public Field_int
+{
+  const Type_handler_general_purpose_int *type_handler_priv() const
+  {
+    if (is_unsigned())
+      return &type_handler_uint24;
+    return &type_handler_sint24;
+  }
+public:
+  Field_medium(uchar *ptr_arg, uint32 len_arg, uchar *null_ptr_arg,
+	      uchar null_bit_arg,
+	      enum utype unireg_check_arg, const LEX_CSTRING *field_name_arg,
+	      bool zero_arg, bool unsigned_arg)
+    :Field_int(ptr_arg, len_arg, null_ptr_arg, null_bit_arg,
+               unireg_check_arg, field_name_arg, zero_arg, unsigned_arg)
+    {}
+  const Type_handler *type_handler() const override
+  { return type_handler_priv(); }
+  enum ha_base_keytype key_type() const override
+    { return unsigned_flag ? HA_KEYTYPE_UINT24 : HA_KEYTYPE_INT24; }
+  int store(const char *to,size_t length,CHARSET_INFO *charset) override;
+  int store(double nr) override;
+  int store(longlong nr, bool unsigned_val) override;
+  int reset() override { ptr[0]=ptr[1]=ptr[2]=0; return 0; }
+  double val_real() override;
+  longlong val_int() override;
+  String *val_str(String *, String *) override;
+  bool send(Protocol *protocol) override;
+  int cmp(const uchar *,const uchar *) const override;
+  void sort_string(uchar *buff,uint length) override;
+  uint32 pack_length() const override { return 3; }
+  const Type_limits_int *type_limits_int() const override
+  {
+    return type_handler_priv()->type_limits_int();
+  }
+  uchar *pack(uchar* to, const uchar *from, uint max_length) override
+  {
+    return Field::pack(to, from, max_length);
+  }
+  ulonglong get_max_int_value() const override
+  {
+    return unsigned_flag ? 0xFFFFFFULL : 0x7FFFFFULL;
+  }
+};
+
+
+class Field_long final :public Field_int
+{
+  const Type_handler_general_purpose_int *type_handler_priv() const
+  {
+    if (is_unsigned())
+      return &type_handler_ulong;
+    return &type_handler_slong;
+  }
+public:
+  Field_long(uchar *ptr_arg, uint32 len_arg, uchar *null_ptr_arg,
+	     uchar null_bit_arg,
+	     enum utype unireg_check_arg, const LEX_CSTRING *field_name_arg,
+	     bool zero_arg, bool unsigned_arg)
+    :Field_int(ptr_arg, len_arg, null_ptr_arg, null_bit_arg,
+               unireg_check_arg, field_name_arg, zero_arg, unsigned_arg)
+    {}
+  Field_long(uint32 len_arg,bool maybe_null_arg,
+             const LEX_CSTRING *field_name_arg,
+	     bool unsigned_arg)
+    :Field_int((uchar*) 0, len_arg, maybe_null_arg ? (uchar*) "": 0,0,
+               NONE, field_name_arg, 0, unsigned_arg)
+    {}
+  const Type_handler *type_handler() const override
+  { return type_handler_priv(); }
+  enum ha_base_keytype key_type() const override
+    { return unsigned_flag ? HA_KEYTYPE_ULONG_INT : HA_KEYTYPE_LONG_INT; }
+  int store(const char *to,size_t length,CHARSET_INFO *charset) override;
+  int store(double nr) override;
+  int store(longlong nr, bool unsigned_val) override;
+  int reset() override { ptr[0]=ptr[1]=ptr[2]=ptr[3]=0; return 0; }
+  double val_real() override;
+  longlong val_int() override;
+  bool send(Protocol *protocol) override;
+  String *val_str(String *, String *) override;
+  int cmp(const uchar *,const uchar *) const override;
+  void sort_string(uchar *buff,uint length) override;
+  uint32 pack_length() const override { return 4; }
+  const Type_limits_int *type_limits_int() const override
+  {
+    return type_handler_priv()->type_limits_int();
+  }
+  uchar *pack(uchar* to, const uchar *from, uint) override
+  {
+    return pack_int32(to, from);
+  }
+  const uchar *unpack(uchar* to, const uchar *from,
+                      const uchar *from_end, uint) override
+  {
+    return unpack_int32(to, from, from_end);
+  }
+  ulonglong get_max_int_value() const override
+  {
+    return unsigned_flag ? 0xFFFFFFFFULL : 0x7FFFFFFFULL;
+  }
+};
+
+
+class Field_longlong :public Field_int
+{
+  const Type_handler_general_purpose_int *type_handler_priv() const
+  {
+    if (is_unsigned())
+      return &type_handler_ulonglong;
+    return &type_handler_slonglong;
+  }
+public:
+  Field_longlong(uchar *ptr_arg, uint32 len_arg, uchar *null_ptr_arg,
+	      uchar null_bit_arg,
+	      enum utype unireg_check_arg, const LEX_CSTRING *field_name_arg,
+	      bool zero_arg, bool unsigned_arg)
+    :Field_int(ptr_arg, len_arg, null_ptr_arg, null_bit_arg,
+               unireg_check_arg, field_name_arg, zero_arg, unsigned_arg)
+    {}
+  Field_longlong(uint32 len_arg,bool maybe_null_arg,
+		 const LEX_CSTRING *field_name_arg,
+                 bool unsigned_arg)
+    :Field_int((uchar*) 0, len_arg, maybe_null_arg ? (uchar*) "": 0,0,
+                NONE, field_name_arg, 0, unsigned_arg)
+    {}
+  const Type_handler *type_handler() const override
+  { return type_handler_priv(); }
+  enum ha_base_keytype key_type() const override
+  { return unsigned_flag ? HA_KEYTYPE_ULONGLONG : HA_KEYTYPE_LONGLONG; }
+  int store(const char *to,size_t length,CHARSET_INFO *charset) override;
+  int store(double nr) override;
+  int store(longlong nr, bool unsigned_val) override;
+  int reset() override
+  {
+    ptr[0]=ptr[1]=ptr[2]=ptr[3]=ptr[4]=ptr[5]=ptr[6]=ptr[7]=0;
+    return 0;
+  }
+  double val_real() override;
+  longlong val_int() override;
+  String *val_str(String *, String *) override;
+  bool send(Protocol *protocol) override;
+  int cmp(const uchar *,const uchar *) const override;
+  void sort_string(uchar *buff,uint length) override;
+  uint32 pack_length() const override { return 8; }
+  const Type_limits_int *type_limits_int() const override
+  {
+    return type_handler_priv()->type_limits_int();
+  }
+  uchar *pack(uchar* to, const uchar *from, uint) override
+  {
+    return pack_int64(to, from);
+  }
+  const uchar *unpack(uchar* to, const uchar *from, const uchar *from_end,
+		      uint) override
+  {
+    return unpack_int64(to, from, from_end);
+  }
+  void set_max() override;
+  bool is_max() override;
+  ulonglong get_max_int_value() const override
+  {
+    return unsigned_flag ? 0xFFFFFFFFFFFFFFFFULL : 0x7FFFFFFFFFFFFFFFULL;
+  }
+};
+
+
+class Field_vers_trx_id :public Field_longlong {
+  MYSQL_TIME cache;
+  ulonglong cached;
+public:
+  Field_vers_trx_id(uchar *ptr_arg, uint32 len_arg, uchar *null_ptr_arg,
+                    uchar null_bit_arg, enum utype unireg_check_arg,
+                    const LEX_CSTRING *field_name_arg, bool zero_arg,
+                    bool unsigned_arg)
+      : Field_longlong(ptr_arg, len_arg, null_ptr_arg, null_bit_arg,
+                       unireg_check_arg, field_name_arg, zero_arg,
+                       unsigned_arg),
+        cached(0)
+  {}
+  const Type_handler *type_handler() const override
+  { return &type_handler_vers_trx_id; }
+  uint size_of() const override { return sizeof *this; }
+  bool get_date(MYSQL_TIME *ltime, date_mode_t fuzzydate, ulonglong trx_id);
+  bool get_date(MYSQL_TIME *ltime, date_mode_t fuzzydate) override
+  {
+    return get_date(ltime, fuzzydate, (ulonglong) val_int());
+  }
+  bool test_if_equality_guarantees_uniqueness(const Item *item) const override;
+  bool can_optimize_keypart_ref(const Item_bool_func *, const Item *)
+    const override
+  {
+    return true;
+  }
+
+  bool can_optimize_group_min_max(const Item_bool_func *, const Item *)
+    const override
+  {
+    return true;
+  }
+  bool can_optimize_range(const Item_bool_func *, const Item *, bool)
+    const override
+  {
+    return true;
+  }
+  /* cmp_type() cannot be TIME_RESULT, because we want to compare this field against
+     integers. But in all other cases we treat it as TIME_RESULT! */
+};
+
+
+class Field_float final :public Field_real {
+public:
+  Field_float(uchar *ptr_arg, uint32 len_arg, uchar *null_ptr_arg,
+	      uchar null_bit_arg,
+	      enum utype unireg_check_arg, const LEX_CSTRING *field_name_arg,
+              uint8 dec_arg,bool zero_arg,bool unsigned_arg)
+    :Field_real(ptr_arg, len_arg, null_ptr_arg, null_bit_arg,
+                unireg_check_arg, field_name_arg,
+                dec_arg, zero_arg, unsigned_arg)
+    {
+      if (dec_arg >= FLOATING_POINT_DECIMALS)
+        dec_arg= NOT_FIXED_DEC;
+    }
+  Field_float(uint32 len_arg, bool maybe_null_arg,
+              const LEX_CSTRING *field_name_arg, uint8 dec_arg)
+    :Field_real((uchar*) 0, len_arg, maybe_null_arg ? (uchar*) "": 0, (uint) 0,
+                NONE, field_name_arg, dec_arg, 0, 0)
+    {
+      if (dec_arg >= FLOATING_POINT_DECIMALS)
+        dec_arg= NOT_FIXED_DEC;
+    }
+  const Type_handler *type_handler() const override
+  { return &type_handler_float; }
+  enum ha_base_keytype key_type() const override { return HA_KEYTYPE_FLOAT; }
+  int store(const char *to,size_t length,CHARSET_INFO *charset) override;
+  int store(double nr) override;
+  int store(longlong nr, bool unsigned_val) override;
+  int reset() override { bzero(ptr,sizeof(float)); return 0; }
+  double val_real() override;
+  longlong val_int() override;
+  String *val_str(String *, String *) override;
+  bool send(Protocol *protocol) override;
+  int cmp(const uchar *,const uchar *) const override;
+  void sort_string(uchar *buff, uint length) override;
+  uint32 pack_length() const override { return sizeof(float); }
+  uint row_pack_length() const override { return pack_length(); }
+  ulonglong get_max_int_value() const override
+  {
+    /*
+      We use the maximum as per IEEE754-2008 standard, 2^24
+    */
+    return 0x1000000ULL;
+  }
+  Binlog_type_info binlog_type_info() const override;
+};
+
+
+class Field_double :public Field_real {
+  longlong val_int_from_real(bool want_unsigned_result);
+public:
+  Field_double(uchar *ptr_arg, uint32 len_arg, uchar *null_ptr_arg,
+	       uchar null_bit_arg,
+	       enum utype unireg_check_arg, const LEX_CSTRING *field_name_arg,
+	       uint8 dec_arg,bool zero_arg,bool unsigned_arg)
+    :Field_real(ptr_arg, len_arg, null_ptr_arg, null_bit_arg,
+                unireg_check_arg, field_name_arg,
+                dec_arg, zero_arg, unsigned_arg)
+    {
+      if (dec_arg >= FLOATING_POINT_DECIMALS)
+        dec_arg= NOT_FIXED_DEC;
+    }
+  Field_double(uint32 len_arg, bool maybe_null_arg,
+               const LEX_CSTRING *field_name_arg, uint8 dec_arg)
+    :Field_real((uchar*) 0, len_arg, maybe_null_arg ? (uchar*) "" : 0, (uint) 0,
+                NONE, field_name_arg, dec_arg, 0, 0)
+    {
+      if (dec_arg >= FLOATING_POINT_DECIMALS)
+        dec_arg= NOT_FIXED_DEC;
+    }
+  Field_double(uint32 len_arg, bool maybe_null_arg,
+               const LEX_CSTRING *field_name_arg,
+	       uint8 dec_arg, bool not_fixed_arg)
+    :Field_real((uchar*) 0, len_arg, maybe_null_arg ? (uchar*) "" : 0, (uint) 0,
+                NONE, field_name_arg, dec_arg, 0, 0)
+    {
+      not_fixed= not_fixed_arg;
+      if (dec_arg >= FLOATING_POINT_DECIMALS)
+        dec_arg= NOT_FIXED_DEC;
+    }
+  void init_for_tmp_table(Field *org_field, TABLE *new_table) override
+  {
+    Field::init_for_tmp_table(org_field, new_table);
+    not_fixed= true;
+  }
+  const Type_handler *type_handler() const override
+  { return &type_handler_double; }
+  enum ha_base_keytype key_type() const override final { return HA_KEYTYPE_DOUBLE; }
+  int  store(const char *to,size_t length,CHARSET_INFO *charset) override final;
+  int  store(double nr) override final;
+  int  store(longlong nr, bool unsigned_val) override final;
+  int reset() override final { bzero(ptr,sizeof(double)); return 0; }
+  double val_real() override final;
+  longlong val_int() override final { return val_int_from_real(false); }
+  ulonglong val_uint() override final { return (ulonglong) val_int_from_real(true); }
+  String *val_str(String *, String *) override final;
+  bool send(Protocol *protocol) override;
+  int cmp(const uchar *,const uchar *) const override final;
+  void sort_string(uchar *buff, uint length) override final;
+  uint32 pack_length() const override final { return sizeof(double); }
+  uint row_pack_length() const override final { return pack_length(); }
+  ulonglong get_max_int_value() const override final
+  {
+    /*
+      We use the maximum as per IEEE754-2008 standard, 2^53
+    */
+    return 0x20000000000000ULL;
+  }
+  Binlog_type_info binlog_type_info() const override final;
+};
+
+
+/* Everything saved in this will disappear. It will always return NULL */
+
+class Field_null :public Field_str {
+  static uchar null[1];
+public:
+  Field_null(uchar *ptr_arg, uint32 len_arg,
+	     enum utype unireg_check_arg, const LEX_CSTRING *field_name_arg,
+	     const DTCollation &collation)
+    :Field_str(ptr_arg, len_arg, null, 1,
+	       unireg_check_arg, field_name_arg, collation)
+    {}
+  const Type_handler *type_handler() const override
+  { return &type_handler_null; }
+  enum_conv_type rpl_conv_type_from(const Conv_source &source,
+                                    const Relay_log_info *rli,
+                                    const Conv_param &param) const override;
+  Information_schema_character_attributes
+    information_schema_character_attributes() const override
+  {
+    return Information_schema_character_attributes();
+  }
+  Copy_func *get_copy_func(const Field *from) const override
+  {
+    return do_field_string;
+  }
+  int  store(const char *to, size_t length, CHARSET_INFO *cs) override final
+  { null[0]=1; return 0; }
+  int store(double nr) override final { null[0]=1; return 0; }
+  int store(longlong nr, bool unsigned_val) override final { null[0]=1; return 0; }
+  int store_decimal(const my_decimal *d) override final { null[0]=1; return 0; }
+  int reset() override final { return 0; }
+  double val_real() override final { return 0.0;}
+  longlong val_int() override final { return 0;}
+  bool val_bool() override final { return false; }
+  my_decimal *val_decimal(my_decimal *) override final { return 0; }
+  String *val_str(String *value,String *value2) override final
+  { value2->length(0); return value2;}
+  bool is_equal(const Column_definition &new_field) const override final;
+  int cmp(const uchar *a, const uchar *b) const override final { return 0;}
+  void sort_string(uchar *buff, uint length) override final {}
+  uint32 pack_length() const override final { return 0; }
+  void sql_type(String &str) const override final;
+  uint size_of() const override final { return sizeof *this; }
+  uint32 max_display_length() const override final { return 4; }
+  void move_field_offset(my_ptrdiff_t ptr_diff) override final {}
+  bool can_optimize_keypart_ref(const Item_bool_func *cond,
+                                const Item *item) const override final
+  {
+    return false;
+  }
+  bool can_optimize_group_min_max(const Item_bool_func *cond,
+                                  const Item *const_item) const override final
+  {
+    return false;
+  }
+};
+
+
+class Field_temporal :public Field {
+protected:
+  Item *get_equal_const_item_datetime(THD *thd, const Context &ctx,
+                                      Item *const_item);
+  void set_warnings(Sql_condition::enum_warning_level trunc_level,
+                    const ErrConv *str, int was_cut, const char *typestr);
+  int store_TIME_return_code_with_warnings(int warn, const ErrConv *str,
+                                           const char *typestr)
+  {
+    if (!MYSQL_TIME_WARN_HAVE_WARNINGS(warn) &&
+        MYSQL_TIME_WARN_HAVE_NOTES(warn))
+    {
+      set_warnings(Sql_condition::WARN_LEVEL_NOTE, str,
+                   warn | MYSQL_TIME_WARN_TRUNCATED, typestr);
+      return 3;
+    }
+    set_warnings(Sql_condition::WARN_LEVEL_WARN, str, warn, typestr);
+    return warn ? 2 : 0;
+  }
+  int store_invalid_with_warning(const ErrConv *str, int was_cut,
+                                 const char *typestr)
+  {
+    DBUG_ASSERT(was_cut);
+    reset();
+    Sql_condition::enum_warning_level level= Sql_condition::WARN_LEVEL_WARN;
+    if (was_cut & MYSQL_TIME_WARN_ZERO_DATE)
+    {
+      set_warnings(level, str, MYSQL_TIME_WARN_OUT_OF_RANGE, typestr);
+      return 2;
+    }
+    set_warnings(level, str, MYSQL_TIME_WARN_TRUNCATED, typestr);
+    return 1;
+  }
+  void sql_type_comment(String &str,
+                        const Name &name,
+                        const Name &comment) const;
+  void sql_type_dec_comment(String &str,
+                            const Name &name, uint dec,
+                            const Name &comment) const;
+  void sql_type_opt_dec_comment(String &str,
+                                const Name &name, uint dec,
+                                const Name &comment) const
+  {
+    if (dec)
+      sql_type_dec_comment(str, name, dec, comment);
+    else
+      sql_type_comment(str, name, comment);
+  }
+  static const Name &type_version_mysql56();
+public:
+  Field_temporal(uchar *ptr_arg,uint32 len_arg, uchar *null_ptr_arg,
+                 uchar null_bit_arg, utype unireg_check_arg,
+                 const LEX_CSTRING *field_name_arg)
+    :Field(ptr_arg, len_arg, null_ptr_arg, null_bit_arg, unireg_check_arg,
+               field_name_arg)
+    { flags|= BINARY_FLAG; }
+  int  store_hex_hybrid(const char *str, size_t length) override
+  {
+    return store(str, length, &my_charset_bin);
+  }
+  sql_mode_t can_handle_sql_mode_dependency_on_store() const override;
+  Copy_func *get_copy_func(const Field *from) const override;
+  int save_in_field(Field *to) override
+  {
+    MYSQL_TIME ltime;
+    // For temporal types no truncation needed. Rounding mode is not important.
+    if (get_date(&ltime, TIME_CONV_NONE | TIME_FRAC_NONE))
+      return to->reset();
+    return to->store_time_dec(&ltime, decimals());
+  }
+  bool memcpy_field_possible(const Field *from) const override;
+  uint32 max_display_length() const override { return field_length; }
+  bool str_needs_quotes() const override { return true; }
+  CHARSET_INFO *charset() const override
+  {
+    return DTCollation_numeric::singleton().collation;
+  }
+  const DTCollation &dtcollation() const override
+  {
+    return DTCollation_numeric::singleton();
+  }
+  CHARSET_INFO *sort_charset() const override { return &my_charset_bin; }
+  bool binary() const override { return true; }
+  bool val_bool() override { return val_real() != 0e0; }
+  bool is_equal(const Column_definition &new_field) const override;
+  bool eq_def(const Field *field) const override
+  {
+    return (Field::eq_def(field) && decimals() == field->decimals());
+  }
+  my_decimal *val_decimal(my_decimal*) override;
+  double pos_in_interval(Field *min, Field *max) override
+  {
+    return pos_in_interval_val_real(min, max);
+  }
+  bool can_optimize_keypart_ref(const Item_bool_func *cond,
+                                const Item *item) const override;
+  bool can_optimize_group_min_max(const Item_bool_func *cond,
+                                  const Item *const_item) const override;
+  bool can_optimize_range(const Item_bool_func *cond,
+                                  const Item *item,
+                                  bool is_eq_func) const override
+  {
+    return true;
+  }
+  SEL_ARG *get_mm_leaf(RANGE_OPT_PARAM *param, KEY_PART *key_part,
+                       const Item_bool_func *cond,
+                       scalar_comparison_op op, Item *value) override;
+};
+
+
+/**
+  Abstract class for:
+  - DATE
+  - DATETIME
+  - DATETIME(1..6)
+  - DATETIME(0..6) - MySQL56 version
+*/
+class Field_temporal_with_date :public Field_temporal {
+protected:
+  virtual void store_TIME(const MYSQL_TIME *ltime) = 0;
+  void store_datetime(const Datetime &dt)
+  {
+    return store_TIME(dt.get_mysql_time());
+  }
+  virtual bool get_TIME(MYSQL_TIME *ltime, const uchar *pos,
+                        date_mode_t fuzzydate) const = 0;
+  bool validate_MMDD(bool not_zero_date, uint month, uint day,
+                     date_mode_t fuzzydate) const
+  {
+    if (!not_zero_date)
+      return bool(fuzzydate & TIME_NO_ZERO_DATE);
+    if (!month || !day)
+      return bool(fuzzydate & TIME_NO_ZERO_IN_DATE);
+    return false;
+  }
+public:
+  Field_temporal_with_date(uchar *ptr_arg, uint32 len_arg,
+                           uchar *null_ptr_arg, uchar null_bit_arg,
+                           utype unireg_check_arg,
+                           const LEX_CSTRING *field_name_arg)
+    :Field_temporal(ptr_arg, len_arg, null_ptr_arg, null_bit_arg,
+                    unireg_check_arg, field_name_arg)
+    {}
+  bool validate_value_in_record(THD *thd, const uchar *record) const;
+};
+
+
+class Field_timestamp :public Field_temporal {
+protected:
+  int store_TIME_with_warning(THD *, const Datetime *,
+                              const ErrConv *, int warn);
+  virtual void store_TIMEVAL(const timeval &tv)= 0;
+  void store_TIMESTAMP(const Timestamp &ts)
+  {
+    store_TIMEVAL(ts.tv());
+  }
+  int zero_time_stored_return_code_with_warning();
+public:
+  Field_timestamp(uchar *ptr_arg, uint32 len_arg,
+                  uchar *null_ptr_arg, uchar null_bit_arg,
+		  enum utype unireg_check_arg,
+                  const LEX_CSTRING *field_name_arg,
+		  TABLE_SHARE *share);
+  const Type_handler *type_handler() const override
+  { return &type_handler_timestamp; }
+  enum_conv_type rpl_conv_type_from(const Conv_source &source,
+                                    const Relay_log_info *rli,
+                                    const Conv_param &param) const override;
+  Copy_func *get_copy_func(const Field *from) const override;
+  sql_mode_t conversion_depends_on_sql_mode(THD *, Item *) const override;
+  int  store(const char *to,size_t length,CHARSET_INFO *charset) override;
+  int  store(double nr) override;
+  int  store(longlong nr, bool unsigned_val) override;
+  int  store_time_dec(const MYSQL_TIME *ltime, uint dec) override;
+  int  store_decimal(const my_decimal *) override;
+  int  store_timestamp_dec(const timeval &ts, uint dec) override;
+  int  save_in_field(Field *to) override;
+  longlong val_int() override;
+  String *val_str(String *, String *) override;
+  bool zero_pack() const override { return false; }
+  /*
+    This method is used by storage/perfschema and
+    Item_func_now_local::save_in_field().
+  */
+  void store_TIME(my_time_t ts, ulong sec_part)
+  {
+    int warn;
+    time_round_mode_t mode= Datetime::default_round_mode(get_thd());
+    store_TIMESTAMP(Timestamp(ts, sec_part).round(decimals(), mode, &warn));
+  }
+  bool get_date(MYSQL_TIME *ltime, date_mode_t fuzzydate) override;
+  int store_native(const Native &value) override;
+  bool validate_value_in_record(THD *thd, const uchar *record) const override;
+  Item *get_equal_const_item(THD *thd, const Context &ctx, Item *const_item)
+    override
+  {
+    return get_equal_const_item_datetime(thd, ctx, const_item);
+  }
+  bool load_data_set_null(THD *thd) override;
+  bool load_data_set_no_data(THD *thd, bool fixed_format) override;
+};
+
+
+class Field_timestamp0 :public Field_timestamp
+{
+  void store_TIMEVAL(const timeval &tv) override
+  {
+    int4store(ptr, tv.tv_sec);
+  }
+public:
+  Field_timestamp0(uchar *ptr_arg, uint32 len_arg,
+                   uchar *null_ptr_arg, uchar null_bit_arg,
+		   enum utype unireg_check_arg,
+                   const LEX_CSTRING *field_name_arg,
+		   TABLE_SHARE *share)
+   :Field_timestamp(ptr_arg, len_arg, null_ptr_arg, null_bit_arg,
+                    unireg_check_arg, field_name_arg, share)
+  { }
+  enum ha_base_keytype key_type() const override
+  { return HA_KEYTYPE_ULONG_INT; }
+  void sql_type(String &str) const override
+  {
+    sql_type_comment(str, Field_timestamp0::type_handler()->name(),
+                     Type_handler::version_mariadb53());
+  }
+  double val_real() override
+  {
+    return (double) Field_timestamp0::val_int();
+  }
+  bool send(Protocol *protocol) override;
+  int cmp(const uchar *,const uchar *) const override;
+  void sort_string(uchar *buff,uint length) override;
+  uint32 pack_length() const override { return 4; }
+  int set_time() override;
+  /* Get TIMESTAMP field value as seconds since begging of Unix Epoch */
+  my_time_t get_timestamp(const uchar *pos, ulong *sec_part) const override;
+  bool val_native(Native *to) override;
+  uchar *pack(uchar *to, const uchar *from, uint) override
+  {
+    return pack_int32(to, from);
+  }
+  const uchar *unpack(uchar* to, const uchar *from, const uchar *from_end,
+                      uint) override
+  {
+    return unpack_int32(to, from, from_end);
+  }
+  uint size_of() const override { return sizeof *this; }
+};
+
+
+/**
+  Abstract class for:
+  - TIMESTAMP(1..6)
+  - TIMESTAMP(0..6) - MySQL56 version
+*/
+class Field_timestamp_with_dec :public Field_timestamp {
+protected:
+  uint dec;
+public:
+  Field_timestamp_with_dec(uchar *ptr_arg,
+                           uchar *null_ptr_arg, uchar null_bit_arg,
+                           enum utype unireg_check_arg,
+                           const LEX_CSTRING *field_name_arg,
+                           TABLE_SHARE *share, uint dec_arg) :
+  Field_timestamp(ptr_arg,
+                  MAX_DATETIME_WIDTH + dec_arg + MY_TEST(dec_arg), null_ptr_arg,
+                  null_bit_arg, unireg_check_arg, field_name_arg, share),
+  dec(dec_arg)
+  {
+    DBUG_ASSERT(dec <= TIME_SECOND_PART_DIGITS);
+  }
+  uint decimals() const override { return dec; }
+  enum ha_base_keytype key_type() const override { return HA_KEYTYPE_BINARY; }
+  uchar *pack(uchar *to, const uchar *from, uint max_length) override
+  { return Field::pack(to, from, max_length); }
+  const uchar *unpack(uchar* to, const uchar *from, const uchar *from_end,
+                      uint param_data) override
+  { return Field::unpack(to, from, from_end, param_data); }
+  void make_send_field(Send_field *field) override;
+  void sort_string(uchar *to, uint length) override
+  {
+    DBUG_ASSERT(length == pack_length());
+    memcpy(to, ptr, length);
+  }
+  bool send(Protocol *protocol) override;
+  double val_real() override;
+  my_decimal* val_decimal(my_decimal*) override;
+  int set_time() override;
+};
+
+
+class Field_timestamp_hires :public Field_timestamp_with_dec {
+  uint sec_part_bytes(uint dec) const
+  {
+    return Type_handler_timestamp::sec_part_bytes(dec);
+  }
+  void store_TIMEVAL(const timeval &tv) override;
+public:
+  Field_timestamp_hires(uchar *ptr_arg,
+                        uchar *null_ptr_arg, uchar null_bit_arg,
+                        enum utype unireg_check_arg,
+                        const LEX_CSTRING *field_name_arg,
+                        TABLE_SHARE *share, uint dec_arg) :
+  Field_timestamp_with_dec(ptr_arg, null_ptr_arg, null_bit_arg,
+                           unireg_check_arg, field_name_arg, share, dec_arg)
+  {
+    DBUG_ASSERT(dec);
+  }
+  void sql_type(String &str) const override
+  {
+    sql_type_dec_comment(str, Field_timestamp_hires::type_handler()->name(),
+                         dec, Type_handler::version_mariadb53());
+  }
+  bool val_native(Native *to) override;
+  my_time_t get_timestamp(const uchar *pos, ulong *sec_part) const override;
+  int cmp(const uchar *,const uchar *) const override;
+  uint32 pack_length() const override { return 4 + sec_part_bytes(dec); }
+  uint size_of() const override { return sizeof *this; }
+};
+
+
+/**
+  TIMESTAMP(0..6) - MySQL56 version
+*/
+class Field_timestampf final :public Field_timestamp_with_dec {
+  void store_TIMEVAL(const timeval &tv) override;
+public:
+  Field_timestampf(uchar *ptr_arg,
+                   uchar *null_ptr_arg, uchar null_bit_arg,
+                   enum utype unireg_check_arg,
+                   const LEX_CSTRING *field_name_arg,
+                   TABLE_SHARE *share, uint dec_arg) :
+    Field_timestamp_with_dec(ptr_arg, null_ptr_arg, null_bit_arg,
+                             unireg_check_arg, field_name_arg, share, dec_arg)
+    {}
+  const Type_handler *type_handler() const override
+  { return &type_handler_timestamp2; }
+  enum_field_types binlog_type() const override
+  { return MYSQL_TYPE_TIMESTAMP2; }
+  void sql_type(String &str) const override
+  {
+    sql_type_opt_dec_comment(str, Field_timestampf::type_handler()->name(),
+                             dec, type_version_mysql56());
+
+  }
+  enum_conv_type rpl_conv_type_from(const Conv_source &source,
+                                    const Relay_log_info *rli,
+                                    const Conv_param &param) const override;
+  uint32 pack_length() const override
+  {
+    return my_timestamp_binary_length(dec);
+  }
+  uint row_pack_length() const override { return pack_length(); }
+  uint pack_length_from_metadata(uint field_metadata) const override
+  {
+    DBUG_ENTER("Field_timestampf::pack_length_from_metadata");
+    uint tmp= my_timestamp_binary_length(field_metadata);
+    DBUG_RETURN(tmp);
+  }
+  int cmp(const uchar *a_ptr,const uchar *b_ptr) const override
+  {
+    return memcmp(a_ptr, b_ptr, pack_length());
+  }
+  void set_max() override;
+  bool is_max() override;
+  my_time_t get_timestamp(const uchar *pos, ulong *sec_part) const override;
+  bool val_native(Native *to) override;
+  uint size_of() const override { return sizeof *this; }
+  Binlog_type_info binlog_type_info() const override;
+};
+
+
+class Field_year final :public Field_tiny {
+public:
+  Field_year(uchar *ptr_arg, uint32 len_arg, uchar *null_ptr_arg,
+	     uchar null_bit_arg,
+	     enum utype unireg_check_arg, const LEX_CSTRING *field_name_arg)
+    :Field_tiny(ptr_arg, len_arg, null_ptr_arg, null_bit_arg,
+		unireg_check_arg, field_name_arg, 1, 1)
+    {}
+  const Type_handler *type_handler() const override
+  {
+    return field_length == 2 ? &type_handler_year2 : &type_handler_year;
+  }
+  enum_conv_type rpl_conv_type_from(const Conv_source &source,
+                                    const Relay_log_info *rli,
+                                    const Conv_param &param) const override;
+  Copy_func *get_copy_func(const Field *from) const override
+  {
+    if (eq_def(from))
+      return get_identical_copy_func();
+    switch (from->cmp_type()) {
+    case STRING_RESULT:
+    {
+      const Type_handler *handler= from->type_handler();
+      if (handler == &type_handler_enum || handler == &type_handler_set)
+        return do_field_int;
+      return do_field_string;
+    }
+    case TIME_RESULT:
+      return do_field_date;
+    case DECIMAL_RESULT:
+      return do_field_decimal;
+    case REAL_RESULT:
+      return do_field_real;
+    case INT_RESULT:
+      break;
+    case ROW_RESULT:
+    default:
+      DBUG_ASSERT(0);
+      break;
+    }
+    return do_field_int;
+  }
+  int  store(const char *to,size_t length,CHARSET_INFO *charset) override;
+  int  store(double nr) override;
+  int  store(longlong nr, bool unsigned_val) override;
+  int  store_time_dec(const MYSQL_TIME *ltime, uint dec) override;
+  double val_real() override;
+  longlong val_int() override;
+  String *val_str(String *, String *) override;
+  bool get_date(MYSQL_TIME *ltime, date_mode_t fuzzydate) override;
+  bool send(Protocol *protocol) override;
+  Information_schema_numeric_attributes
+    information_schema_numeric_attributes() const override
+  {
+    return Information_schema_numeric_attributes();
+  }
+  uint32 max_display_length() const override { return field_length; }
+  void sql_type(String &str) const override;
+};
+
+
+class Field_date_common :public Field_temporal_with_date
+{
+protected:
+  int store_TIME_with_warning(const Datetime *ltime, const ErrConv *str,
+                              int was_cut);
+public:
+  Field_date_common(uchar *ptr_arg, uchar *null_ptr_arg, uchar null_bit_arg,
+                    enum utype unireg_check_arg,
+                    const LEX_CSTRING *field_name_arg)
+    :Field_temporal_with_date(ptr_arg, MAX_DATE_WIDTH,
+                              null_ptr_arg, null_bit_arg,
+                              unireg_check_arg, field_name_arg)
+  {}
+  Copy_func *get_copy_func(const Field *from) const override;
+  SEL_ARG *get_mm_leaf(RANGE_OPT_PARAM *param, KEY_PART *key_part,
+                       const Item_bool_func *cond,
+                       scalar_comparison_op op, Item *value) override;
+  int  store(const char *to, size_t length, CHARSET_INFO *charset) override;
+  int  store(double nr) override;
+  int  store(longlong nr, bool unsigned_val) override;
+  int  store_time_dec(const MYSQL_TIME *ltime, uint dec) override;
+  int  store_decimal(const my_decimal *) override;
+};
+
+
+class Field_date final :public Field_date_common
+{
+  void store_TIME(const MYSQL_TIME *ltime) override;
+  bool get_TIME(MYSQL_TIME *ltime, const uchar *pos, date_mode_t fuzzydate)
+    const override;
+public:
+  Field_date(uchar *ptr_arg, uchar *null_ptr_arg, uchar null_bit_arg,
+	     enum utype unireg_check_arg, const LEX_CSTRING *field_name_arg)
+    :Field_date_common(ptr_arg, null_ptr_arg, null_bit_arg,
+                       unireg_check_arg, field_name_arg) {}
+  const Type_handler *type_handler() const override
+  { return &type_handler_date; }
+  enum ha_base_keytype key_type() const override
+  { return HA_KEYTYPE_ULONG_INT; }
+  enum_conv_type rpl_conv_type_from(const Conv_source &source,
+                                    const Relay_log_info *rli,
+                                    const Conv_param &param) const override;
+  int reset() override { ptr[0]=ptr[1]=ptr[2]=ptr[3]=0; return 0; }
+  bool get_date(MYSQL_TIME *ltime, date_mode_t fuzzydate) override
+  { return Field_date::get_TIME(ltime, ptr, fuzzydate); }
+  double val_real() override;
+  longlong val_int() override;
+  String *val_str(String *, String *) override;
+  bool send(Protocol *protocol) override;
+  int cmp(const uchar *,const uchar *) const override;
+  void sort_string(uchar *buff,uint length) override;
+  uint32 pack_length() const override { return 4; }
+  void sql_type(String &str) const override;
+  uchar *pack(uchar* to, const uchar *from, uint) override
+  {
+    return pack_int32(to, from);
+  }
+  const uchar *unpack(uchar* to, const uchar *from, const uchar *from_end,
+                      uint) override
+  {
+    return unpack_int32(to, from, from_end);
+  }
+  uint size_of() const override { return sizeof *this; }
+};
+
+
+class Field_newdate final :public Field_date_common
+{
+  void store_TIME(const MYSQL_TIME *ltime) override;
+  bool get_TIME(MYSQL_TIME *ltime, const uchar *pos, date_mode_t fuzzydate)
+    const override;
+public:
+  Field_newdate(uchar *ptr_arg, uchar *null_ptr_arg, uchar null_bit_arg,
+		enum utype unireg_check_arg, const LEX_CSTRING *field_name_arg)
+    :Field_date_common(ptr_arg, null_ptr_arg, null_bit_arg,
+                       unireg_check_arg, field_name_arg)
+    {}
+  const Type_handler *type_handler() const override
+  { return &type_handler_newdate; }
+  enum ha_base_keytype key_type() const override { return HA_KEYTYPE_UINT24; }
+  enum_conv_type rpl_conv_type_from(const Conv_source &source,
+                                    const Relay_log_info *rli,
+                                    const Conv_param &param) const override;
+  int reset() override { ptr[0]=ptr[1]=ptr[2]=0; return 0; }
+  double val_real() override;
+  longlong val_int() override;
+  String *val_str(String *, String *) override;
+  bool send(Protocol *protocol) override;
+  int cmp(const uchar *,const uchar *) const override;
+  void sort_string(uchar *buff,uint length) override;
+  uint32 pack_length() const override { return 3; }
+  void sql_type(String &str) const override;
+  bool get_date(MYSQL_TIME *ltime, date_mode_t fuzzydate) override
+  { return Field_newdate::get_TIME(ltime, ptr, fuzzydate); }
+  longlong val_datetime_packed(THD *thd) override;
+  uint size_of() const override { return sizeof *this; }
+  Item *get_equal_const_item(THD *thd, const Context &ctx, Item *const_item)
+    override;
+};
+
+
+class Field_time :public Field_temporal {
+  /*
+    when this Field_time instance is used for storing values for index lookups
+    (see class store_key, Field::new_key_field(), etc), the following
+    might be set to TO_DAYS(CURDATE()). See also Field_time::store_time_dec()
+  */
+  long curdays;
+protected:
+  virtual void store_TIME(const MYSQL_TIME *ltime)= 0;
+  void store_TIME(const Time &t) { return store_TIME(t.get_mysql_time()); }
+  int store_TIME_with_warning(const Time *ltime, const ErrConv *str, int warn);
+  bool check_zero_in_date_with_warn(date_mode_t fuzzydate);
+  static void do_field_time(Copy_field *copy);
+public:
+  Field_time(uchar *ptr_arg, uint length_arg, uchar *null_ptr_arg,
+             uchar null_bit_arg, enum utype unireg_check_arg,
+             const LEX_CSTRING *field_name_arg)
+    :Field_temporal(ptr_arg, length_arg, null_ptr_arg, null_bit_arg,
+                    unireg_check_arg, field_name_arg), curdays(0)
+    {}
+  bool can_be_substituted_to_equal_item(const Context &ctx,
+                                        const Item_equal *item_equal) override;
+  const Type_handler *type_handler() const override
+  { return &type_handler_time; }
+  enum_conv_type rpl_conv_type_from(const Conv_source &source,
+                                    const Relay_log_info *rli,
+                                    const Conv_param &param) const override;
+  Copy_func *get_copy_func(const Field *from) const override
+  {
+    return from->cmp_type() == REAL_RESULT ? do_field_string : // MDEV-9344
+           from->type() == MYSQL_TYPE_YEAR ? do_field_int :
+           from->type() == MYSQL_TYPE_BIT  ? do_field_int :
+           eq_def(from)                    ? get_identical_copy_func() :
+                                             do_field_time;
+  }
+  bool memcpy_field_possible(const Field *from) const override
+  {
+    return real_type() == from->real_type() &&
+           decimals() == from->decimals();
+  }
+  sql_mode_t conversion_depends_on_sql_mode(THD *, Item *) const override;
+  int store_native(const Native &value) override;
+  bool val_native(Native *to) override;
+  int store_time_dec(const MYSQL_TIME *ltime, uint dec) override;
+  int store(const char *to,size_t length,CHARSET_INFO *charset) override;
+  int store(double nr) override;
+  int store(longlong nr, bool unsigned_val) override;
+  int  store_decimal(const my_decimal *) override;
+  String *val_str(String *, String *) override;
+  bool send(Protocol *protocol) override;
+  void set_curdays(THD *thd);
+  Field *new_key_field(MEM_ROOT *root, TABLE *new_table,
+                       uchar *new_ptr, uint32 length,
+                       uchar *new_null_ptr, uint new_null_bit) override;
+  Item *get_equal_const_item(THD *thd, const Context &ctx, Item *const_item)
+    override;
+};
+
+
+class Field_time0 final :public Field_time
+{
+protected:
+  void store_TIME(const MYSQL_TIME *ltime) override;
+public:
+  Field_time0(uchar *ptr_arg, uint length_arg, uchar *null_ptr_arg,
+             uchar null_bit_arg, enum utype unireg_check_arg,
+             const LEX_CSTRING *field_name_arg)
+    :Field_time(ptr_arg, length_arg, null_ptr_arg, null_bit_arg,
+                unireg_check_arg, field_name_arg)
+  { }
+  enum ha_base_keytype key_type() const override { return HA_KEYTYPE_INT24; }
+  void sql_type(String &str) const override
+  {
+    sql_type_comment(str, Field_time0::type_handler()->name(),
+                     Type_handler::version_mariadb53());
+  }
+  double val_real() override;
+  longlong val_int() override;
+  bool get_date(MYSQL_TIME *ltime, date_mode_t fuzzydate) override;
+  int cmp(const uchar *,const uchar *) const override;
+  void sort_string(uchar *buff,uint length) override;
+  uint32 pack_length() const override { return 3; }
+  uint size_of() const override { return sizeof *this; }
+};
+
+
+/**
+  Abstract class for:
+  - TIME(1..6)
+  - TIME(0..6) - MySQL56 version
+*/
+class Field_time_with_dec :public Field_time {
+protected:
+  uint dec;
+public:
+  Field_time_with_dec(uchar *ptr_arg, uchar *null_ptr_arg, uchar null_bit_arg,
+                      enum utype unireg_check_arg,
+                      const LEX_CSTRING *field_name_arg,
+                      uint dec_arg)
+    :Field_time(ptr_arg, MIN_TIME_WIDTH + dec_arg + MY_TEST(dec_arg),
+                null_ptr_arg, null_bit_arg, unireg_check_arg, field_name_arg),
+     dec(dec_arg)
+  {
+    DBUG_ASSERT(dec <= TIME_SECOND_PART_DIGITS);
+  }
+  uint decimals() const override { return dec; }
+  enum ha_base_keytype key_type() const override { return HA_KEYTYPE_BINARY; }
+  longlong val_int() override;
+  double val_real() override;
+  void make_send_field(Send_field *) override;
+};
+
+
+/**
+  TIME(1..6)
+*/
+class Field_time_hires final :public Field_time_with_dec {
+  longlong zero_point;
+  void store_TIME(const MYSQL_TIME *) override;
+public:
+  Field_time_hires(uchar *ptr_arg, uchar *null_ptr_arg, uchar null_bit_arg,
+             enum utype unireg_check_arg, const LEX_CSTRING *field_name_arg,
+             uint dec_arg)
+    :Field_time_with_dec(ptr_arg, null_ptr_arg,
+                         null_bit_arg, unireg_check_arg, field_name_arg,
+                         dec_arg)
+  {
+    DBUG_ASSERT(dec);
+    zero_point= sec_part_shift(
+                   ((TIME_MAX_VALUE_SECONDS+1LL)*TIME_SECOND_PART_FACTOR), dec);
+  }
+  void sql_type(String &str) const override
+  {
+    sql_type_dec_comment(str, Field_time_hires::type_handler()->name(),
+                         dec, Type_handler::version_mariadb53());
+  }
+  int reset() override;
+  bool get_date(MYSQL_TIME *ltime, date_mode_t fuzzydate) override;
+  int cmp(const uchar *,const uchar *) const override;
+  void sort_string(uchar *buff,uint length) override;
+  uint32 pack_length() const override
+  { return Type_handler_time::hires_bytes(dec); }
+  uint size_of() const override { return sizeof *this; }
+};
+
+
+/**
+  TIME(0..6) - MySQL56 version
+*/
+class Field_timef final :public Field_time_with_dec {
+  void store_TIME(const MYSQL_TIME *ltime) override;
+public:
+  Field_timef(uchar *ptr_arg, uchar *null_ptr_arg, uchar null_bit_arg,
+             enum utype unireg_check_arg, const LEX_CSTRING *field_name_arg,
+             uint dec_arg)
+    :Field_time_with_dec(ptr_arg, null_ptr_arg,
+                         null_bit_arg, unireg_check_arg, field_name_arg,
+                         dec_arg)
+  {
+    DBUG_ASSERT(dec <= TIME_SECOND_PART_DIGITS);
+  }
+  const Type_handler *type_handler() const override
+  { return &type_handler_time2; }
+  enum_field_types binlog_type() const override { return MYSQL_TYPE_TIME2; }
+  void sql_type(String &str) const override
+  {
+    sql_type_opt_dec_comment(str, Field_timef::type_handler()->name(),
+                             dec, type_version_mysql56());
+  }
+  enum_conv_type rpl_conv_type_from(const Conv_source &source,
+                                    const Relay_log_info *rli,
+                                    const Conv_param &param) const override;
+  uint32 pack_length() const override
+  {
+    return my_time_binary_length(dec);
+  }
+  uint row_pack_length() const override { return pack_length(); }
+  uint pack_length_from_metadata(uint field_metadata) const override
+  {
+    DBUG_ENTER("Field_timef::pack_length_from_metadata");
+    uint tmp= my_time_binary_length(field_metadata);
+    DBUG_RETURN(tmp);
+  }
+  void sort_string(uchar *to, uint length) override
+  {
+    DBUG_ASSERT(length == Field_timef::pack_length());
+    memcpy(to, ptr, length);
+  }
+  int cmp(const uchar *a_ptr, const uchar *b_ptr) const override
+  {
+    return memcmp(a_ptr, b_ptr, pack_length());
+  }
+  int reset() override;
+  bool get_date(MYSQL_TIME *ltime, date_mode_t fuzzydate) override;
+  longlong val_time_packed(THD *thd) override;
+  int store_native(const Native &value) override;
+  bool val_native(Native *to) override;
+  uint size_of() const override { return sizeof *this; }
+  Binlog_type_info binlog_type_info() const override;
+};
+
+
+class Field_datetime :public Field_temporal_with_date {
+protected:
+  int store_TIME_with_warning(const Datetime *ltime, const ErrConv *str,
+                              int was_cut);
+public:
+  Field_datetime(uchar *ptr_arg, uint length_arg, uchar *null_ptr_arg,
+                 uchar null_bit_arg, enum utype unireg_check_arg,
+                 const LEX_CSTRING *field_name_arg)
+    :Field_temporal_with_date(ptr_arg, length_arg, null_ptr_arg, null_bit_arg,
+                              unireg_check_arg, field_name_arg)
+    {
+      if (unireg_check == TIMESTAMP_UN_FIELD ||
+          unireg_check == TIMESTAMP_DNUN_FIELD)
+        flags|= ON_UPDATE_NOW_FLAG;
+    }
+  const Type_handler *type_handler() const override
+  { return &type_handler_datetime; }
+  sql_mode_t conversion_depends_on_sql_mode(THD *, Item *) const override;
+  enum_conv_type rpl_conv_type_from(const Conv_source &source,
+                                    const Relay_log_info *rli,
+                                    const Conv_param &param) const override;
+  int  store(const char *to, size_t length, CHARSET_INFO *charset) override;
+  int  store(double nr) override;
+  int  store(longlong nr, bool unsigned_val) override;
+  int  store_time_dec(const MYSQL_TIME *ltime, uint dec) override;
+  int  store_decimal(const my_decimal *) override;
+  int set_time() override;
+  Item *get_equal_const_item(THD *thd, const Context &ctx, Item *const_item)
+    override
+  {
+    return get_equal_const_item_datetime(thd, ctx, const_item);
+  }
+};
+
+
+/*
+  Stored as a 8 byte unsigned int. Should sometimes be change to a 6 byte
+*/
+
+class Field_datetime0 final :public Field_datetime
+{
+  void store_TIME(const MYSQL_TIME *ltime) override;
+  bool get_TIME(MYSQL_TIME *ltime, const uchar *pos, date_mode_t fuzzydate)
+    const override;
+public:
+  Field_datetime0(uchar *ptr_arg, uint length_arg, uchar *null_ptr_arg,
+                 uchar null_bit_arg, enum utype unireg_check_arg,
+                 const LEX_CSTRING *field_name_arg)
+    :Field_datetime(ptr_arg, length_arg, null_ptr_arg, null_bit_arg,
+                    unireg_check_arg, field_name_arg)
+  {}
+  enum ha_base_keytype key_type() const override
+  { return HA_KEYTYPE_ULONGLONG; }
+  void sql_type(String &str) const override
+  {
+    sql_type_comment(str, Field_datetime0::type_handler()->name(),
+                     Type_handler::version_mariadb53());
+  }
+  double val_real() override
+  {
+    return (double) Field_datetime0::val_int();
+  }
+  longlong val_int() override;
+  String *val_str(String *, String *) override;
+  bool send(Protocol *protocol) override;
+  int cmp(const uchar *,const uchar *) const override;
+  void sort_string(uchar *buff,uint length) override;
+  uint32 pack_length() const override { return 8; }
+  bool get_date(MYSQL_TIME *ltime, date_mode_t fuzzydate) override
+  { return Field_datetime0::get_TIME(ltime, ptr, fuzzydate); }
+  uchar *pack(uchar* to, const uchar *from, uint) override
+  {
+    return pack_int64(to, from);
+  }
+  const uchar *unpack(uchar* to, const uchar *from, const uchar *from_end,
+		      uint) override
+  {
+    return unpack_int64(to, from, from_end);
+  }
+  uint size_of() const override { return sizeof *this; }
+};
+
+
+/**
+  Abstract class for:
+  - DATETIME(1..6)
+  - DATETIME(0..6) - MySQL56 version
+*/
+class Field_datetime_with_dec :public Field_datetime {
+protected:
+  uint dec;
+public:
+  Field_datetime_with_dec(uchar *ptr_arg, uchar *null_ptr_arg,
+                          uchar null_bit_arg, enum utype unireg_check_arg,
+                          const LEX_CSTRING *field_name_arg, uint dec_arg)
+    :Field_datetime(ptr_arg, MAX_DATETIME_WIDTH + dec_arg + MY_TEST(dec_arg),
+                    null_ptr_arg, null_bit_arg, unireg_check_arg,
+                    field_name_arg), dec(dec_arg)
+  {
+    DBUG_ASSERT(dec <= TIME_SECOND_PART_DIGITS);
+  }
+  uint decimals() const override final { return dec; }
+  enum ha_base_keytype key_type() const override final { return HA_KEYTYPE_BINARY; }
+  void make_send_field(Send_field *field) override final;
+  bool send(Protocol *protocol) override final;
+  uchar *pack(uchar *to, const uchar *from, uint max_length) override final
+  { return Field::pack(to, from, max_length); }
+  const uchar *unpack(uchar* to, const uchar *from, const uchar *from_end,
+                      uint param_data) override final
+  { return Field::unpack(to, from, from_end, param_data); }
+  void sort_string(uchar *to, uint length) override final
+  {
+    DBUG_ASSERT(length == pack_length());
+    memcpy(to, ptr, length);
+  }
+  double val_real() override final;
+  longlong val_int() override final;
+  String *val_str(String *, String *) override final;
+};
+
+
+/**
+  DATETIME(1..6)
+*/
+class Field_datetime_hires final :public Field_datetime_with_dec {
+  void store_TIME(const MYSQL_TIME *ltime) override;
+  bool get_TIME(MYSQL_TIME *ltime, const uchar *pos, date_mode_t fuzzydate)
+    const override;
+public:
+  Field_datetime_hires(uchar *ptr_arg, uchar *null_ptr_arg,
+                       uchar null_bit_arg, enum utype unireg_check_arg,
+                       const LEX_CSTRING *field_name_arg, uint dec_arg)
+    :Field_datetime_with_dec(ptr_arg, null_ptr_arg, null_bit_arg,
+                             unireg_check_arg, field_name_arg, dec_arg)
+  {
+    DBUG_ASSERT(dec);
+  }
+  void sql_type(String &str) const override
+  {
+    sql_type_dec_comment(str, Field_datetime_hires::type_handler()->name(),
+                         dec, Type_handler::version_mariadb53());
+  }
+  int cmp(const uchar *,const uchar *) const override;
+  uint32 pack_length() const override
+  { return Type_handler_datetime::hires_bytes(dec); }
+  bool get_date(MYSQL_TIME *ltime, date_mode_t fuzzydate) override
+  { return Field_datetime_hires::get_TIME(ltime, ptr, fuzzydate); }
+  uint size_of() const override { return sizeof *this; }
+};
+
+
+/**
+  DATETIME(0..6) - MySQL56 version
+*/
+
+class Field_datetimef final :public Field_datetime_with_dec {
+  void store_TIME(const MYSQL_TIME *ltime) override;
+  bool get_TIME(MYSQL_TIME *ltime, const uchar *pos, date_mode_t fuzzydate)
+    const override;
+public:
+  Field_datetimef(uchar *ptr_arg, uchar *null_ptr_arg,
+                  uchar null_bit_arg, enum utype unireg_check_arg,
+                  const LEX_CSTRING *field_name_arg, uint dec_arg)
+    :Field_datetime_with_dec(ptr_arg, null_ptr_arg, null_bit_arg,
+                             unireg_check_arg, field_name_arg, dec_arg)
+  {}
+  const Type_handler *type_handler() const override
+  { return &type_handler_datetime2; }
+  enum_field_types binlog_type() const override
+  { return MYSQL_TYPE_DATETIME2; }
+  void sql_type(String &str) const override
+  {
+    sql_type_opt_dec_comment(str, Field_datetimef::type_handler()->name(),
+                             dec, type_version_mysql56());
+  }
+  enum_conv_type rpl_conv_type_from(const Conv_source &source,
+                                    const Relay_log_info *rli,
+                                    const Conv_param &param) const override;
+  uint32 pack_length() const override
+  {
+    return my_datetime_binary_length(dec);
+  }
+  uint row_pack_length() const override { return pack_length(); }
+  uint pack_length_from_metadata(uint field_metadata) const override
+  {
+    DBUG_ENTER("Field_datetimef::pack_length_from_metadata");
+    uint tmp= my_datetime_binary_length(field_metadata);
+    DBUG_RETURN(tmp);
+  }
+  int cmp(const uchar *a_ptr, const uchar *b_ptr) const override
+  {
+    return memcmp(a_ptr, b_ptr, pack_length());
+  }
+  int reset() override;
+  bool get_date(MYSQL_TIME *ltime, date_mode_t fuzzydate) override
+  { return Field_datetimef::get_TIME(ltime, ptr, fuzzydate); }
+  longlong val_datetime_packed(THD *thd) override;
+  uint size_of() const override { return sizeof *this; }
+  Binlog_type_info binlog_type_info() const override;
+};
+
+
+static inline Field_timestamp *
+new_Field_timestamp(MEM_ROOT *root,uchar *ptr, uchar *null_ptr, uchar null_bit,
+                    enum Field::utype unireg_check,
+                    const LEX_CSTRING *field_name,
+                    TABLE_SHARE *share, uint dec)
+{
+  if (dec==0)
+    return new (root)
+      Field_timestamp0(ptr, MAX_DATETIME_WIDTH, null_ptr,
+                       null_bit, unireg_check, field_name, share);
+  if (dec >= FLOATING_POINT_DECIMALS)
+    dec= MAX_DATETIME_PRECISION;
+  return new (root)
+    Field_timestamp_hires(ptr, null_ptr, null_bit, unireg_check,
+                          field_name, share, dec);
+}
+
+static inline Field_time *
+new_Field_time(MEM_ROOT *root, uchar *ptr, uchar *null_ptr, uchar null_bit,
+               enum Field::utype unireg_check, const LEX_CSTRING *field_name,
+               uint dec)
+{
+  if (dec == 0)
+    return new (root)
+      Field_time0(ptr, MIN_TIME_WIDTH, null_ptr, null_bit, unireg_check,
+                  field_name);
+  if (dec >= FLOATING_POINT_DECIMALS)
+    dec= MAX_DATETIME_PRECISION;
+  return new (root)
+    Field_time_hires(ptr, null_ptr, null_bit, unireg_check, field_name, dec);
+}
+
+static inline Field_datetime *
+new_Field_datetime(MEM_ROOT *root, uchar *ptr, uchar *null_ptr, uchar null_bit,
+                   enum Field::utype unireg_check,
+                   const LEX_CSTRING *field_name, uint dec)
+{
+  if (dec == 0)
+    return new (root)
+      Field_datetime0(ptr, MAX_DATETIME_WIDTH, null_ptr, null_bit,
+                      unireg_check, field_name);
+  if (dec >= FLOATING_POINT_DECIMALS)
+    dec= MAX_DATETIME_PRECISION;
+  return new (root)
+    Field_datetime_hires(ptr, null_ptr, null_bit,
+                         unireg_check, field_name, dec);
+}
+
+class Field_string final :public Field_longstr {
+  class Warn_filter_string: public Warn_filter
+  {
+  public:
+    Warn_filter_string(const THD *thd, const Field_string *field);
+  };
+  bool is_var_string() const
+  {
+    return can_alter_field_type &&
+           orig_table &&
+           (orig_table->s->db_create_options & HA_OPTION_PACK_RECORD) &&
+           field_length >= 4 &&
+           orig_table->s->frm_version < FRM_VER_TRUE_VARCHAR;
+  }
+public:
+  bool can_alter_field_type;
+  Field_string(uchar *ptr_arg, uint32 len_arg,uchar *null_ptr_arg,
+	       uchar null_bit_arg,
+	       enum utype unireg_check_arg, const LEX_CSTRING *field_name_arg,
+	       const DTCollation &collation)
+    :Field_longstr(ptr_arg, len_arg, null_ptr_arg, null_bit_arg,
+                   unireg_check_arg, field_name_arg, collation),
+     can_alter_field_type(1) {};
+  Field_string(uint32 len_arg,bool maybe_null_arg,
+               const LEX_CSTRING *field_name_arg,
+               const DTCollation &collation)
+    :Field_longstr((uchar*) 0, len_arg, maybe_null_arg ? (uchar*) "": 0, 0,
+                   NONE, field_name_arg, collation),
+     can_alter_field_type(1) {};
+
+  const Type_handler *type_handler() const override
+  {
+    if (is_var_string())
+      return &type_handler_var_string;
+    return &type_handler_string;
+  }
+  enum ha_base_keytype key_type() const override
+    { return binary() ? HA_KEYTYPE_BINARY : HA_KEYTYPE_TEXT; }
+  en_fieldtype tmp_engine_column_type(bool use_packed_rows) const override;
+  bool zero_pack() const override { return false; }
+  Copy_func *get_copy_func(const Field *from) const override;
+  int reset() override
+  {
+    charset()->fill((char*) ptr, field_length, (has_charset() ? ' ' : 0));
+    return 0;
+  }
+  int store(const char *to,size_t length,CHARSET_INFO *charset) override;
+  using Field_str::store;
+  double val_real() override;
+  longlong val_int() override;
+  String *val_str(String *, String *) override;
+  my_decimal *val_decimal(my_decimal *) override;
+  int cmp(const uchar *,const uchar *) const override;
+  void sort_string(uchar *buff,uint length) override;
+  void update_data_type_statistics(Data_type_statistics *st) const override
+  {
+    st->m_fixed_string_count++;
+    st->m_fixed_string_total_length+= pack_length();
+  }
+  void sql_type(String &str) const override;
+  void sql_rpl_type(String*) const override;
+  bool is_equal(const Column_definition &new_field) const override;
+  bool can_be_converted_by_engine(const Column_definition &new_type) const
+    override
+  {
+    return table->file->can_convert_string(this, new_type);
+  }
+  uchar *pack(uchar *to, const uchar *from, uint max_length) override;
+  const uchar *unpack(uchar* to, const uchar *from, const uchar *from_end,
+                      uint param_data) override;
+  uint pack_length_from_metadata(uint field_metadata) const override
+  {
+    DBUG_PRINT("debug", ("field_metadata: 0x%04x", field_metadata));
+    if (field_metadata == 0)
+      return row_pack_length();
+    return (((field_metadata >> 4) & 0x300) ^ 0x300) + (field_metadata & 0x00ff);
+  }
+  bool compatible_field_size(uint field_metadata, const Relay_log_info *rli,
+                             uint16 mflags, int *order_var) const override;
+  uint row_pack_length() const override { return field_length; }
+  int pack_cmp(const uchar *a,const uchar *b,uint key_length,
+               bool insert_or_update);
+  int pack_cmp(const uchar *b,uint key_length,bool insert_or_update);
+  uint packed_col_length(const uchar *to, uint length) override;
+  uint max_packed_col_length(uint max_length) override;
+  uint size_of() const override { return sizeof *this; }
+  bool has_charset() const override { return charset() != &my_charset_bin; }
+  Field *make_new_field(MEM_ROOT *root, TABLE *new_table, bool keep_type)
+    override;
+  uint get_key_image(uchar *buff, uint length,
+                     const uchar *ptr_arg, imagetype type) const override;
+  sql_mode_t value_depends_on_sql_mode() const override;
+  sql_mode_t can_handle_sql_mode_dependency_on_store() const override;
+  void print_key_value(String *out, uint32 length) override;
+  Binlog_type_info binlog_type_info() const override;
+};
+
+
+class Field_varstring :public Field_longstr {
+public:
+  const uchar *get_data() const
+  {
+    return get_data(ptr);
+  }
+  const uchar *get_data(const uchar *ptr_arg) const
+  {
+    return ptr_arg + length_bytes;
+  }
+  uint get_length() const
+  {
+    return get_length(ptr);
+  }
+  uint get_length(const uchar *ptr_arg) const
+  {
+    return length_bytes == 1 ? (uint) *ptr_arg : uint2korr(ptr_arg);
+  }
+protected:
+  void store_length(uint32 number)
+  {
+    if (length_bytes == 1)
+      *ptr= (uchar) number;
+    else
+      int2store(ptr, number);
+  }
+  virtual void val_str_from_ptr(String *val, const uchar *ptr) const;
+public:
+  /*
+    The maximum space available in a Field_varstring, in bytes. See
+    length_bytes.
+  */
+  static const uint MAX_SIZE;
+  /* Store number of bytes used to store length (1 or 2) */
+  uint32 length_bytes;
+  Field_varstring(uchar *ptr_arg,
+                  uint32 len_arg, uint length_bytes_arg,
+                  uchar *null_ptr_arg, uchar null_bit_arg,
+		  enum utype unireg_check_arg, const LEX_CSTRING *field_name_arg,
+		  TABLE_SHARE *share, const DTCollation &collation)
+    :Field_longstr(ptr_arg, len_arg, null_ptr_arg, null_bit_arg,
+                   unireg_check_arg, field_name_arg, collation),
+     length_bytes(length_bytes_arg)
+  {
+    share->varchar_fields++;
+  }
+  Field_varstring(uint32 len_arg,bool maybe_null_arg,
+                  const LEX_CSTRING *field_name_arg,
+                  TABLE_SHARE *share, const DTCollation &collation)
+    :Field_longstr((uchar*) 0,len_arg, maybe_null_arg ? (uchar*) "": 0, 0,
+                   NONE, field_name_arg, collation),
+     length_bytes(len_arg < 256 ? 1 :2)
+  {
+    share->varchar_fields++;
+  }
+
+  const Type_handler *type_handler() const override
+  { return &type_handler_varchar; }
+  en_fieldtype tmp_engine_column_type(bool use_packed_rows) const override
+  {
+    return FIELD_VARCHAR;
+  }
+  enum ha_base_keytype key_type() const override;
+  uint16 key_part_flag() const override { return HA_VAR_LENGTH_PART; }
+  uint16 key_part_length_bytes() const override { return HA_KEY_BLOB_LENGTH; }
+  uint row_pack_length() const override { return field_length; }
+  bool zero_pack() const override { return false; }
+  int  reset() override { bzero(ptr,field_length+length_bytes); return 0; }
+  uint32 pack_length() const override
+  { return (uint32) field_length+length_bytes; }
+  uint32 key_length() const override { return (uint32) field_length; }
+  uint32 sort_length() const override
+  {
+    return (uint32) field_length + sort_suffix_length();
+  }
+  virtual uint32 sort_suffix_length() const override
+  {
+    return (field_charset() == &my_charset_bin ? length_bytes : 0);
+  }
+  Copy_func *get_copy_func(const Field *from) const override;
+  bool memcpy_field_possible(const Field *from) const override;
+  void update_data_type_statistics(Data_type_statistics *st) const override
+  {
+    st->m_variable_string_count++;
+    st->m_variable_string_total_length+= pack_length();
+  }
+  int  store(const char *to,size_t length,CHARSET_INFO *charset) override;
+  using Field_str::store;
+#ifdef HAVE_MEM_CHECK
+  void mark_unused_memory_as_defined() override;
+#endif
+  double val_real() override;
+  longlong val_int() override;
+  String *val_str(String *, String *) override;
+  my_decimal *val_decimal(my_decimal *) override;
+  bool send(Protocol *protocol) override;
+  int cmp(const uchar *a,const uchar *b) const override;
+  int cmp_prefix(const uchar *a, const uchar *b, size_t prefix_len) const
+    override;
+  void sort_string(uchar *buff,uint length) override;
+  uint get_key_image(uchar *buff, uint length,
+                     const uchar *ptr_arg, imagetype type) const override;
+  void set_key_image(const uchar *buff,uint length) override;
+  void sql_type(String &str) const override;
+  void sql_rpl_type(String*) const override;
+  uchar *pack(uchar *to, const uchar *from, uint max_length) override;
+  const uchar *unpack(uchar* to, const uchar *from, const uchar *from_end,
+                      uint param_data) override;
+  int cmp_binary(const uchar *a,const uchar *b, uint32 max_length=~0U) const
+    override;
+  int key_cmp(const uchar *,const uchar*) const override;
+  int key_cmp(const uchar *str, uint length) const override;
+  uint packed_col_length(const uchar *to, uint length) override;
+  uint max_packed_col_length(uint max_length) override;
+  uint32 data_length() override;
+  uint size_of() const override { return sizeof *this; }
+  bool has_charset() const override
+  { return charset() == &my_charset_bin ? FALSE : TRUE; }
+  Field *make_new_field(MEM_ROOT *root, TABLE *new_table, bool keep_type)
+    override;
+  Field *new_key_field(MEM_ROOT *root, TABLE *new_table,
+                       uchar *new_ptr, uint32 length,
+                       uchar *new_null_ptr, uint new_null_bit) override;
+  bool is_equal(const Column_definition &new_field) const override;
+  bool can_be_converted_by_engine(const Column_definition &new_type) const
+    override
+  {
+    return table->file->can_convert_varstring(this, new_type);
+  }
+  void hash(ulong *nr, ulong *nr2) override;
+  uint length_size() const override { return length_bytes; }
+  void print_key_value(String *out, uint32 length) override;
+  Binlog_type_info binlog_type_info() const override;
+};
+
+
+class Field_varstring_compressed final :public Field_varstring {
+public:
+  Field_varstring_compressed(uchar *ptr_arg,
+                             uint32 len_arg, uint length_bytes_arg,
+                             uchar *null_ptr_arg, uchar null_bit_arg,
+                             enum utype unireg_check_arg,
+                             const LEX_CSTRING *field_name_arg,
+                             TABLE_SHARE *share, const DTCollation &collation,
+                             Compression_method *compression_method_arg):
+    Field_varstring(ptr_arg, len_arg, length_bytes_arg, null_ptr_arg,
+                    null_bit_arg, unireg_check_arg, field_name_arg,
+                    share, collation),
+    compression_method_ptr(compression_method_arg) { DBUG_ASSERT(len_arg > 0); }
+  Compression_method *compression_method() const override
+  { return compression_method_ptr; }
+private:
+  Compression_method *compression_method_ptr;
+  void val_str_from_ptr(String *val, const uchar *ptr) const override;
+  int store(const char *to, size_t length, CHARSET_INFO *charset) override;
+  using Field_str::store;
+  String *val_str(String *, String *) override;
+  double val_real() override;
+  longlong val_int() override;
+  uint size_of() const override { return sizeof *this; }
+  /*
+    We use the default Field::send() implementation,
+    because the derived optimized version (from Field_longstr)
+    is not suitable for compressed fields.
+  */
+  bool send(Protocol *protocol) override
+  {
+    return Field::send(protocol);
+  }
+  enum_field_types binlog_type() const override
+  { return MYSQL_TYPE_VARCHAR_COMPRESSED; }
+  void sql_type(String &str) const override
+  {
+    Field_varstring::sql_type(str);
+    str.append(STRING_WITH_LEN(" /*!100301 COMPRESSED*/"));
+  }
+  uint32 max_display_length() const override { return field_length - 1; }
+  uint32 character_octet_length() const override { return field_length - 1; }
+  uint32 char_length() const override
+  {
+    return (field_length - 1) / mbmaxlen();
+  }
+  int cmp(const uchar *a_ptr, const uchar *b_ptr) const override;
+
+  /*
+    Compressed fields can't have keys as two rows may have different
+    compression methods or compression levels.
+  */
+
+  int key_cmp(const uchar *str, uint length) const override
+  { DBUG_ASSERT(0); return 0; }
+  using Field_varstring::key_cmp;
+  Binlog_type_info binlog_type_info() const override;
+};
+
+
+static inline uint8 number_storage_requirement(uint32 n)
+{
+  return n < 256 ? 1 : n < 65536 ? 2 : n < 16777216 ? 3 : 4;
+}
+
+
+static inline void store_bigendian(ulonglong num, uchar *to, uint bytes)
+{
+  switch(bytes) {
+  case 1: mi_int1store(to, num); break;
+  case 2: mi_int2store(to, num); break;
+  case 3: mi_int3store(to, num); break;
+  case 4: mi_int4store(to, num); break;
+  case 5: mi_int5store(to, num); break;
+  case 6: mi_int6store(to, num); break;
+  case 7: mi_int7store(to, num); break;
+  case 8: mi_int8store(to, num); break;
+  default: DBUG_ASSERT(0);
+  }
+}
+
+
+static inline longlong read_bigendian(const uchar *from, uint bytes)
+{
+  switch(bytes) {
+  case 1: return mi_uint1korr(from);
+  case 2: return mi_uint2korr(from);
+  case 3: return mi_uint3korr(from);
+  case 4: return mi_uint4korr(from);
+  case 5: return mi_uint5korr(from);
+  case 6: return mi_uint6korr(from);
+  case 7: return mi_uint7korr(from);
+  case 8: return mi_sint8korr(from);
+  default: DBUG_ASSERT(0); return 0;
+  }
+}
+
+static inline void store_lowendian(ulonglong num, uchar *to, uint bytes)
+{
+  switch(bytes) {
+  case 1: *to= (uchar)num;    break;
+  case 2: int2store(to, num); break;
+  case 3: int3store(to, num); break;
+  case 4: int4store(to, num); break;
+  case 8: int8store(to, num); break;
+  default: DBUG_ASSERT(0);
+  }
+}
+
+static inline longlong read_lowendian(const uchar *from, uint bytes)
+{
+  switch(bytes) {
+  case 1: return from[0];
+  case 2: return uint2korr(from);
+  case 3: return uint3korr(from);
+  case 4: return uint4korr(from);
+  case 8: return sint8korr(from);
+  default: DBUG_ASSERT(0); return 0;
+  }
+}
+
+
+extern LEX_CSTRING temp_lex_str;
+
+class Field_blob :public Field_longstr {
+protected:
+  /**
+    The number of bytes used to represent the length of the blob.
+  */
+  uint packlength;
+  
+  /**
+    The 'value'-object is a cache fronting the storage engine.
+  */
+  String value;
+  /**
+     Cache for blob values when reading a row with a virtual blob
+     field. This is needed to not destroy the old cached value when
+     updating the blob with a new value when creating the new row.
+  */
+  String read_value;
+
+  static void do_copy_blob(Copy_field *copy);
+  static void do_conv_blob(Copy_field *copy);
+  uint get_key_image_itRAW(const uchar *ptr_arg, uchar *buff, uint length) const;
+public:
+  Field_blob(uchar *ptr_arg, uchar *null_ptr_arg, uchar null_bit_arg,
+	     enum utype unireg_check_arg, const LEX_CSTRING *field_name_arg,
+	     TABLE_SHARE *share, uint blob_pack_length,
+	     const DTCollation &collation);
+  Field_blob(uint32 len_arg,bool maybe_null_arg, const LEX_CSTRING *field_name_arg,
+             const DTCollation &collation)
+    :Field_longstr((uchar*) 0, len_arg, maybe_null_arg ? (uchar*) "": 0, 0,
+                   NONE, field_name_arg, collation),
+    packlength(4)
+  {
+    flags|= BLOB_FLAG;
+  }
+  Field_blob(uint32 len_arg,bool maybe_null_arg,
+             const LEX_CSTRING *field_name_arg,
+             const DTCollation &collation, bool set_packlength)
+    :Field_longstr((uchar*) 0,len_arg, maybe_null_arg ? (uchar*) "": 0, 0,
+                   NONE, field_name_arg, collation)
+  {
+    flags|= BLOB_FLAG;
+    packlength= set_packlength ? number_storage_requirement(len_arg) : 4;
+  }
+  Field_blob(uint32 packlength_arg)
+    :Field_longstr((uchar*) 0, 0, (uchar*) "", 0, NONE, &temp_lex_str,
+                   system_charset_info),
+    packlength(packlength_arg) {}
+  const Type_handler *type_handler() const override;
+  /* Note that the default copy constructor is used, in clone() */
+  enum_field_types type() const override
+  {
+    /*
+      We cannot return type_handler()->field_type() here.
+      Some pieces of the code (e.g. in engines) rely on the fact
+      that Field::type(), Field::real_type() and Item_field::field_type()
+      return MYSQL_TYPE_BLOB for all blob variants.
+      We should eventually fix all such code pieces to expect
+      all BLOB type codes.
+    */
+    return MYSQL_TYPE_BLOB;
+  }
+  enum_field_types real_type() const override
+  {
+    return MYSQL_TYPE_BLOB;
+  }
+  enum ha_base_keytype key_type() const override
+    { return binary() ? HA_KEYTYPE_VARBINARY2 : HA_KEYTYPE_VARTEXT2; }
+  uint16 key_part_flag() const override { return HA_BLOB_PART; }
+  uint16 key_part_length_bytes() const override { return HA_KEY_BLOB_LENGTH; }
+  en_fieldtype tmp_engine_column_type(bool use_packed_rows) const override
+  {
+    return FIELD_BLOB;
+  }
+  Type_numeric_attributes type_numeric_attributes() const override
+  {
+    return Type_numeric_attributes(Field_blob::max_display_length(),
+                                   decimals(), is_unsigned());
+  }
+  Information_schema_character_attributes
+    information_schema_character_attributes() const override
+  {
+    uint32 octets= Field_blob::character_octet_length();
+    uint32 chars= octets / field_charset()->mbminlen;
+    return Information_schema_character_attributes(octets, chars);
+  }
+  void update_data_type_statistics(Data_type_statistics *st) const override
+  {
+    st->m_blob_count++;
+  }
+  void make_send_field(Send_field *) override;
+  Copy_func *get_copy_func(const Field *from) const override
+  {
+    /*
+    TODO: MDEV-9331
+    if (from->type() == MYSQL_TYPE_BIT)
+      return do_field_int;
+    */
+    if (!(from->flags & BLOB_FLAG) || from->charset() != charset() ||
+        !from->compression_method() != !compression_method())
+      return do_conv_blob;
+    if (from->pack_length() != Field_blob::pack_length())
+      return do_copy_blob;
+    return get_identical_copy_func();
+  }
+  int  store_field(Field *from) override
+  {                                             // Be sure the value is stored
+    if (field_charset() == &my_charset_bin &&
+        from->type_handler()->convert_to_binary_using_val_native())
+    {
+      NativeBuffer<64> tmp;
+      from->val_native(&tmp);
+      value.copy(tmp.ptr(), tmp.length(), &my_charset_bin);
+      return store(value.ptr(), value.length(), &my_charset_bin);
+    }
+    from->val_str(&value);
+    if (table->copy_blobs ||
+        (!value.is_alloced() && from->is_varchar_and_in_write_set()))
+      value.copy();
+    return store(value.ptr(), value.length(), from->charset());
+  }
+  bool memcpy_field_possible(const Field *from) const override
+  {
+    return Field_str::memcpy_field_possible(from) &&
+           !compression_method() == !from->compression_method() &&
+           !table->copy_blobs;
+  }
+  bool make_empty_rec_store_default_value(THD *thd, Item *item) override;
+  int store(const char *to, size_t length, CHARSET_INFO *charset) override;
+  using Field_str::store;
+  double val_real() override;
+  longlong val_int() override;
+  String *val_str(String *, String *) override;
+  my_decimal *val_decimal(my_decimal *) override;
+  int cmp(const uchar *a, const uchar *b) const override;
+  int cmp_prefix(const uchar *a, const uchar *b, size_t prefix_len) const
+    override;
+  int cmp(const uchar *a, uint32 a_length, const uchar *b, uint32 b_length)
+    const;
+  int cmp_binary(const uchar *a,const uchar *b, uint32 max_length=~0U) const
+     override;
+  int key_cmp(const uchar *,const uchar*) const override;
+  int key_cmp(const uchar *str, uint length) const override;
+  /* Never update the value of min_val for a blob field */
+  bool update_min(Field *min_val, bool force_update) override { return false; }
+  /* Never update the value of max_val for a blob field */
+  bool update_max(Field *max_val, bool force_update) override { return false; }
+  uint32 key_length() const override { return 0; }
+  void sort_string(uchar *buff,uint length) override;
+  uint32 pack_length() const override
+  { return (uint32) (packlength + portable_sizeof_char_ptr); }
+
+  /**
+     Return the packed length without the pointer size added. 
+
+     This is used to determine the size of the actual data in the row
+     buffer.
+
+     @returns The length of the raw data itself without the pointer.
+  */
+  uint32 pack_length_no_ptr() const
+  { return (uint32) (packlength); }
+  uint row_pack_length() const override { return pack_length_no_ptr(); }
+  uint32 sort_length() const override;
+  uint32 sort_suffix_length() const override;
+  uint32 value_length() override { return get_length(); }
+  virtual uint32 max_data_length() const override
+  {
+    return (uint32) (((ulonglong) 1 << (packlength*8)) -1);
+  }
+  int reset() override { bzero(ptr, packlength+sizeof(uchar*)); return 0; }
+  void reset_fields() override
+  {
+    bzero((uchar*) &value, sizeof value);
+    bzero((uchar*) &read_value, sizeof read_value);
+  }
+  uint32 get_field_buffer_size() { return value.alloced_length(); }
+  void store_length(uchar *i_ptr, uint i_packlength, uint32 i_number);
+  void store_length(size_t number)
+  {
+    DBUG_ASSERT(number < UINT_MAX32);
+    store_length(ptr, packlength, (uint32)number);
+  }
+  inline uint32 get_length(my_ptrdiff_t row_offset= 0) const
+  { return get_length(ptr+row_offset, this->packlength); }
+  uint32 get_length(const uchar *ptr, uint packlength) const;
+  uint32 get_length(const uchar *ptr_arg) const
+  { return get_length(ptr_arg, this->packlength); }
+  inline uchar *get_ptr() const { return get_ptr(ptr); }
+  inline uchar *get_ptr(const uchar *ptr_arg) const
+  {
+    uchar *s;
+    memcpy(&s, ptr_arg + packlength, sizeof(uchar*));
+    return s;
+  }
+  inline void set_ptr(uchar *length, uchar *data)
+  {
+    memcpy(ptr,length,packlength);
+    memcpy(ptr+packlength, &data,sizeof(char*));
+  }
+  void set_ptr_offset(my_ptrdiff_t ptr_diff, uint32 length, const uchar *data)
+  {
+    uchar *ptr_ofs= ADD_TO_PTR(ptr,ptr_diff,uchar*);
+    store_length(ptr_ofs, packlength, length);
+    memcpy(ptr_ofs+packlength, &data, sizeof(char*));
+  }
+  inline void set_ptr(uint32 length, uchar *data)
+  {
+    set_ptr_offset(0, length, data);
+  }
+  int copy_value(Field_blob *from);
+  uint get_key_image(uchar *buff, uint length,
+                     const uchar *ptr_arg, imagetype type) const override
+  {
+    DBUG_ASSERT(type == itRAW);
+    return get_key_image_itRAW(ptr_arg, buff, length);
+  }
+  void set_key_image(const uchar *buff,uint length) override;
+  Field *new_key_field(MEM_ROOT *root, TABLE *new_table,
+                       uchar *new_ptr, uint32 length,
+                       uchar *new_null_ptr, uint new_null_bit) override;
+  void sql_type(String &str) const override;
+  inline bool copy()
+  {
+    uchar *tmp= get_ptr();
+    if (value.copy((char*) tmp, get_length(), charset()))
+    {
+      Field_blob::reset();
+      return 1;
+    }
+    tmp=(uchar*) value.ptr();
+    memcpy(ptr+packlength, &tmp, sizeof(char*));
+    return 0;
+  }
+  /* store value for the duration of the current read record */
+  inline void swap_value_and_read_value()
+  {
+    read_value.swap(value);
+  }
+  inline void set_value(uchar *data)
+  {
+    /* Set value pointer. Lengths are not important */
+    value.reset((char*) data, 1, 1, &my_charset_bin);
+  }
+  uchar *pack(uchar *to, const uchar *from, uint max_length) override;
+  const uchar *unpack(uchar *to, const uchar *from, const uchar *from_end,
+                      uint param_data) override;
+  uint packed_col_length(const uchar *col_ptr, uint length) override;
+  uint max_packed_col_length(uint max_length) override;
+  void free() override
+  {
+    value.free();
+    read_value.free();
+  }
+  inline void clear_temporary()
+  {
+    uchar *tmp= get_ptr();
+    if (likely(value.ptr() == (char*) tmp))
+      bzero((uchar*) &value, sizeof(value));
+    else
+    {
+      /*
+        Currently read_value should never point to tmp, the following code
+        is mainly here to make things future proof.
+      */
+      if (unlikely(read_value.ptr() == (char*) tmp))
+        bzero((uchar*) &read_value, sizeof(read_value));
+    }
+  }
+  uint size_of() const override { return sizeof *this; }
+  bool has_charset() const override { return charset() != &my_charset_bin; }
+  uint32 max_display_length() const override;
+  uint32 char_length() const override;
+  uint32 character_octet_length() const override;
+  bool is_equal(const Column_definition &new_field) const override;
+  bool can_be_converted_by_engine(const Column_definition &new_type) const
+    override
+  {
+    return table->file->can_convert_blob(this, new_type);
+  }
+  void print_key_value(String *out, uint32 length) override;
+  Binlog_type_info binlog_type_info() const override;
+
+  friend void TABLE::remember_blob_values(String *blob_storage);
+  friend void TABLE::restore_blob_values(String *blob_storage);
+};
+
+
+class Field_blob_compressed final :public Field_blob {
+public:
+  Field_blob_compressed(uchar *ptr_arg, uchar *null_ptr_arg,
+                        uchar null_bit_arg, enum utype unireg_check_arg,
+                        const LEX_CSTRING *field_name_arg, TABLE_SHARE *share,
+                        uint blob_pack_length, const DTCollation &collation,
+                        Compression_method *compression_method_arg):
+    Field_blob(ptr_arg, null_ptr_arg, null_bit_arg, unireg_check_arg,
+               field_name_arg, share, blob_pack_length, collation),
+    compression_method_ptr(compression_method_arg) {}
+  Compression_method *compression_method() const override
+  { return compression_method_ptr; }
+private:
+  Compression_method *compression_method_ptr;
+  int store(const char *to, size_t length, CHARSET_INFO *charset) override;
+  using Field_str::store;
+  String *val_str(String *, String *) override;
+  double val_real() override;
+  longlong val_int() override;
+  /*
+    We use the default Field::send() implementation,
+    because the derived optimized version (from Field_longstr)
+    is not suitable for compressed fields.
+  */
+  bool send(Protocol *protocol) override
+  {
+    return Field::send(protocol);
+  }
+  uint size_of() const override { return sizeof *this; }
+  enum_field_types binlog_type() const override
+  { return MYSQL_TYPE_BLOB_COMPRESSED; }
+  void sql_type(String &str) const override
+  {
+    Field_blob::sql_type(str);
+    str.append(STRING_WITH_LEN(" /*!100301 COMPRESSED*/"));
+  }
+
+  /*
+    Compressed fields can't have keys as two rows may have different
+    compression methods or compression levels.
+  */
+
+  uint get_key_image(uchar *buff, uint length,
+                     const uchar *ptr_arg, imagetype type_arg) const override
+  { DBUG_ASSERT(0); return 0; }
+  void set_key_image(const uchar *, uint) override
+  { DBUG_ASSERT(0); }
+  int key_cmp(const uchar *, const uchar *) const override
+  { DBUG_ASSERT(0); return 0; }
+  int key_cmp(const uchar *, uint) const override
+  { DBUG_ASSERT(0); return 0; }
+  Field *new_key_field(MEM_ROOT *, TABLE *, uchar *, uint32, uchar *, uint)
+    override
+  { DBUG_ASSERT(0); return 0; }
+  Binlog_type_info binlog_type_info() const override;
+};
+
+
+class Field_enum :public Field_str {
+  static void do_field_enum(Copy_field *copy_field);
+  longlong val_int(const uchar *) const;
+protected:
+  uint packlength;
+public:
+  const TYPELIB *typelib;
+  Field_enum(uchar *ptr_arg, uint32 len_arg, uchar *null_ptr_arg,
+             uchar null_bit_arg,
+             enum utype unireg_check_arg, const LEX_CSTRING *field_name_arg,
+             uint packlength_arg,
+             const TYPELIB *typelib_arg,
+             const DTCollation &collation)
+    :Field_str(ptr_arg, len_arg, null_ptr_arg, null_bit_arg,
+	       unireg_check_arg, field_name_arg, collation),
+    packlength(packlength_arg),typelib(typelib_arg)
+  {
+      flags|=ENUM_FLAG;
+  }
+  Field *make_new_field(MEM_ROOT *root, TABLE *new_table, bool keep_type)
+    override;
+  const Type_handler *type_handler() const override
+  { return &type_handler_enum; }
+  enum ha_base_keytype key_type() const override;
+  sql_mode_t can_handle_sql_mode_dependency_on_store() const override;
+  enum_conv_type rpl_conv_type_from(const Conv_source &source,
+                                    const Relay_log_info *rli,
+                                    const Conv_param &param) const override;
+  Copy_func *get_copy_func(const Field *from) const override
+  {
+    if (eq_def(from))
+      return get_identical_copy_func();
+    if (real_type() == MYSQL_TYPE_ENUM &&
+        from->real_type() == MYSQL_TYPE_ENUM)
+      return do_field_enum;
+    if (from->result_type() == STRING_RESULT)
+      return do_field_string;
+    return do_field_int;
+  }
+  int store_field(Field *from) override
+  {
+    if (from->real_type() == MYSQL_TYPE_ENUM && from->val_int() == 0)
+    {
+      store_type(0);
+      return 0;
+    }
+    return from->save_in_field(this);
+  }
+  int save_in_field(Field *to) override
+  {
+    if (to->result_type() != STRING_RESULT)
+      return to->store(val_int(), 0);
+    return save_in_field_str(to);
+  }
+  bool memcpy_field_possible(const Field *from) const override
+  { return false; }
+  void make_empty_rec_reset(THD *) override
+  {
+    if (flags & NOT_NULL_FLAG)
+    {
+      set_notnull();
+      store((longlong) 1, true);
+    }
+    else
+      reset();
+  }
+  int  store(const char *to,size_t length,CHARSET_INFO *charset) override;
+  int  store(double nr) override;
+  int  store(longlong nr, bool unsigned_val) override;
+  double val_real() override;
+  longlong val_int() override;
+  String *val_str(String *, String *) override;
+  int cmp(const uchar *,const uchar *) const override;
+  void sort_string(uchar *buff,uint length) override;
+  uint32 pack_length() const override { return (uint32) packlength; }
+  void store_type(ulonglong value);
+  void sql_type(String &str) const override;
+  uint size_of() const override { return sizeof *this; }
+  uint pack_length_from_metadata(uint field_metadata) const override
+  { return (field_metadata & 0x00ff); }
+  uint row_pack_length() const override { return pack_length(); }
+  bool zero_pack() const override { return false; }
+  bool optimize_range(uint, uint) const override { return false; }
+  bool eq_def(const Field *field) const override;
+  bool has_charset() const override { return true; }
+  /* enum and set are sorted as integers */
+  CHARSET_INFO *sort_charset() const override { return &my_charset_bin; }
+  uint decimals() const override { return 0; }
+  const TYPELIB *get_typelib() const override { return typelib; }
+
+  uchar *pack(uchar *to, const uchar *from, uint max_length) override;
+  const uchar *unpack(uchar *to, const uchar *from, const uchar *from_end,
+                      uint param_data) override;
+
+  bool can_optimize_keypart_ref(const Item_bool_func *cond,
+                                const Item *item) const override;
+  bool can_optimize_group_min_max(const Item_bool_func *, const Item *)
+    const override
+  {
+    /*
+      Can't use GROUP_MIN_MAX optimization for ENUM and SET,
+      because the values are stored as numbers in index,
+      while MIN() and MAX() work as strings.
+      It would return the records with min and max enum numeric indexes.
+     "Bug#45300 MAX() and ENUM type" should be fixed first.
+    */
+    return false;
+  }
+  bool can_optimize_range(const Item_bool_func *cond,
+                          const Item *item,
+                          bool is_eq_func) const override;
+  Binlog_type_info binlog_type_info() const override;
+private:
+  bool is_equal(const Column_definition &new_field) const override;
+};
+
+
+class Field_set final :public Field_enum {
+public:
+  Field_set(uchar *ptr_arg, uint32 len_arg, uchar *null_ptr_arg,
+	    uchar null_bit_arg,
+	    enum utype unireg_check_arg, const LEX_CSTRING *field_name_arg,
+	    uint32 packlength_arg,
+	    const TYPELIB *typelib_arg, const DTCollation &collation)
+    :Field_enum(ptr_arg, len_arg, null_ptr_arg, null_bit_arg,
+		    unireg_check_arg, field_name_arg,
+                packlength_arg,
+                typelib_arg, collation),
+      empty_set_string("", 0, collation.collation)
+    {
+      flags=(flags & ~ENUM_FLAG) | SET_FLAG;
+    }
+  void make_empty_rec_reset(THD *thd) override
+  {
+    Field::make_empty_rec_reset(thd);
+  }
+
+  int  store_field(Field *from) override { return from->save_in_field(this); }
+  int  store(const char *to,size_t length,CHARSET_INFO *charset) override;
+  int  store(double nr) override
+  { return Field_set::store((longlong) nr, FALSE); }
+  int  store(longlong nr, bool unsigned_val) override;
+
+  bool zero_pack() const override { return true; }
+  String *val_str(String *, String *) override;
+  void sql_type(String &str) const override;
+  uint size_of() const override { return sizeof *this; }
+  const Type_handler *type_handler() const override
+  { return &type_handler_set; }
+  bool has_charset() const override { return true; }
+  Binlog_type_info binlog_type_info() const override;
+private:
+  const String empty_set_string;
+};
+
+
+/*
+  Note:
+    To use Field_bit::cmp_binary() you need to copy the bits stored in
+    the beginning of the record (the NULL bytes) to each memory you
+    want to compare (where the arguments point).
+
+    This is the reason:
+    - Field_bit::cmp_binary() is only implemented in the base class
+      (Field::cmp_binary()).
+    - Field::cmp_binary() currently uses pack_length() to calculate how
+      long the data is.
+    - pack_length() includes size of the bits stored in the NULL bytes
+      of the record.
+*/
+class Field_bit :public Field {
+public:
+  uchar *bit_ptr;     // position in record where 'uneven' bits store
+  uchar bit_ofs;      // offset to 'uneven' high bits
+  uint bit_len;       // number of 'uneven' high bits
+  uint bytes_in_rec;
+  Field_bit(uchar *ptr_arg, uint32 len_arg, uchar *null_ptr_arg,
+            uchar null_bit_arg, uchar *bit_ptr_arg, uchar bit_ofs_arg,
+            enum utype unireg_check_arg, const LEX_CSTRING *field_name_arg);
+  const Type_handler *type_handler() const override
+  { return &type_handler_bit; }
+  enum ha_base_keytype key_type() const override { return HA_KEYTYPE_BIT; }
+  uint16 key_part_flag() const override { return HA_BIT_PART; }
+  uint32 key_length() const override
+  { return (uint32) (field_length + 7) / 8; }
+  uint32 max_data_length() const override { return key_length(); }
+  uint32 max_display_length() const override { return field_length; }
+  enum_conv_type rpl_conv_type_from(const Conv_source &source,
+                                    const Relay_log_info *rli,
+                                    const Conv_param &param) const override;
+  CHARSET_INFO *charset() const override { return &my_charset_bin; }
+  const DTCollation & dtcollation() const override;
+  Information_schema_numeric_attributes
+    information_schema_numeric_attributes() const override
+  {
+    return Information_schema_numeric_attributes(field_length);
+  }
+  void update_data_type_statistics(Data_type_statistics *st) const override
+  {
+    st->m_uneven_bit_length+= field_length & 7;
+  }
+  uint size_of() const override { return sizeof *this; }
+  int reset() override
+  {
+    bzero(ptr, bytes_in_rec); 
+    if (bit_ptr && (bit_len > 0))  // reset odd bits among null bits
+      clr_rec_bits(bit_ptr, bit_ofs, bit_len);
+    return 0; 
+  }
+  Copy_func *get_copy_func(const Field *from) const override
+  {
+    if (from->cmp_type() == DECIMAL_RESULT)
+      return do_field_decimal;
+    return do_field_int;
+  }
+  int save_in_field(Field *to) override { return to->store(val_int(), true); }
+  bool memcpy_field_possible(const Field *from) const override{ return false; }
+  int store(const char *to, size_t length, CHARSET_INFO *charset) override;
+  int store(double nr) override;
+  int store(longlong nr, bool unsigned_val) override;
+  int store_decimal(const my_decimal *) override;
+  double val_real() override;
+  longlong val_int() override;
+  String *val_str(String*, String *) override;
+  bool str_needs_quotes() const override { return true; }
+  my_decimal *val_decimal(my_decimal *) override;
+  bool val_bool() override { return val_int() != 0; }
+  int cmp(const uchar *a, const uchar *b) const override
+  {
+    DBUG_ASSERT(ptr == a || ptr == b);
+    if (ptr == a)
+      return Field_bit::key_cmp(b, bytes_in_rec + MY_TEST(bit_len));
+    else
+      return Field_bit::key_cmp(a, bytes_in_rec + MY_TEST(bit_len)) * -1;
+  }
+  int cmp_binary_offset(uint row_offset) override
+  { return cmp_offset(row_offset); }
+  int cmp_prefix(const uchar *a, const uchar *b,
+                 size_t  max_length) const override;
+  int key_cmp(const uchar *a, const uchar *b) const override
+  { return cmp_binary((uchar *) a, (uchar *) b); }
+  int key_cmp(const uchar *str, uint length) const override;
+  int cmp_offset(my_ptrdiff_t row_offset) override;
+  bool update_min(Field *min_val, bool force_update) override
+  {
+    longlong val= val_int();
+    bool update_fl= force_update || val < min_val->val_int();
+    if (update_fl)
+    {
+      min_val->set_notnull();
+      min_val->store(val, FALSE);
+    }
+    return update_fl;
+  }
+  bool update_max(Field *max_val, bool force_update) override
+  {
+    longlong val= val_int();
+    bool update_fl= force_update || val > max_val->val_int();
+    if (update_fl)
+    {
+      max_val->set_notnull();
+      max_val->store(val, FALSE);
+    }
+    return update_fl;
+  }
+  void store_field_value(uchar *val, uint) override
+  {
+    store(*((longlong *)val), TRUE);
+  }
+  double pos_in_interval(Field *min, Field *max) override
+  {
+    return pos_in_interval_val_real(min, max);
+  }
+  void get_image(uchar *buff, uint length,
+                 const uchar *ptr_arg, CHARSET_INFO *cs) const override
+  { get_key_image(buff, length, ptr_arg, itRAW); }
+  void set_image(const uchar *buff,uint length, CHARSET_INFO *cs) override
+  { Field_bit::store((char *) buff, length, cs); }
+  uint get_key_image(uchar *buff, uint length,
+                     const uchar *ptr_arg, imagetype type) const override;
+  void set_key_image(const uchar *buff, uint length) override
+  { Field_bit::store((char*) buff, length, &my_charset_bin); }
+  void sort_string(uchar *buff, uint length) override
+  { get_key_image(buff, length, ptr, itRAW); }
+  uint32 pack_length() const override
+  { return (uint32) (field_length + 7) / 8; }
+  uint32 pack_length_in_rec() const override { return bytes_in_rec; }
+  uint pack_length_from_metadata(uint field_metadata) const override;
+  uint row_pack_length() const override
+  { return (bytes_in_rec + ((bit_len > 0) ? 1 : 0)); }
+  bool compatible_field_size(uint metadata, const Relay_log_info *rli,
+                             uint16 mflags, int *order_var) const override;
+  void sql_type(String &str) const override;
+  uchar *pack(uchar *to, const uchar *from, uint max_length) override;
+  const uchar *unpack(uchar *to, const uchar *from,
+                      const uchar *from_end, uint param_data) override;
+  int set_default() override;
+
+  Field *new_key_field(MEM_ROOT *root, TABLE *new_table,
+                       uchar *new_ptr, uint32 length,
+                       uchar *new_null_ptr, uint new_null_bit) override;
+  void set_bit_ptr(uchar *bit_ptr_arg, uchar bit_ofs_arg)
+  {
+    bit_ptr= bit_ptr_arg;
+    bit_ofs= bit_ofs_arg;
+  }
+  bool eq(Field *field) override
+  {
+    return (Field::eq(field) &&
+            bit_ptr == ((Field_bit *)field)->bit_ptr &&
+            bit_ofs == ((Field_bit *)field)->bit_ofs);
+  }
+  bool is_equal(const Column_definition &new_field) const override;
+  void move_field_offset(my_ptrdiff_t ptr_diff) override
+  {
+    Field::move_field_offset(ptr_diff);
+
+    /*
+      clang does not like when things are added to a null pointer, even if
+      it is never referenced.
+    */
+    if (bit_ptr)
+      bit_ptr= ADD_TO_PTR(bit_ptr, ptr_diff, uchar*);
+  }
+  void hash(ulong *nr, ulong *nr2) override;
+
+  SEL_ARG *get_mm_leaf(RANGE_OPT_PARAM *param, KEY_PART *key_part,
+                       const Item_bool_func *cond,
+                       scalar_comparison_op op, Item *value) override
+  {
+    return get_mm_leaf_int(param, key_part, cond, op, value, true);
+  }
+  void print_key_value(String *out, uint32 length) override
+  {
+    val_int_as_str(out, 1);
+  }
+  /**
+     Save the field metadata for bit fields.
+     Saves the bit length in the first byte and bytes in record in the
+     second byte of the field metadata array at index of *metadata_ptr and
+     *(metadata_ptr + 1).
+
+     @param   metadata_ptr   First byte of field metadata
+
+     @returns number of bytes written to metadata_ptr
+  */
+  Binlog_type_info binlog_type_info() const override
+  {
+    DBUG_PRINT("debug", ("bit_len: %d, bytes_in_rec: %d",
+                       bit_len, bytes_in_rec));
+    /*
+      Since this class and Field_bit_as_char have different ideas of
+      what should be stored here, we compute the values of the metadata
+      explicitly using the field_length.
+    */
+    return Binlog_type_info(type(),
+                            static_cast<uint16>((field_length & 7) |
+                                                ((field_length / 8) << 8)), 2);
+  }
+
+private:
+  size_t do_last_null_byte() const override;
+};
+
+
+/**
+  BIT field represented as chars for non-MyISAM tables.
+
+  @todo The inheritance relationship is backwards since Field_bit is
+  an extended version of Field_bit_as_char and not the other way
+  around. Hence, we should refactor it to fix the hierarchy order.
+ */
+class Field_bit_as_char final :public Field_bit {
+public:
+  Field_bit_as_char(uchar *ptr_arg, uint32 len_arg, uchar *null_ptr_arg,
+                    uchar null_bit_arg,
+                    enum utype unireg_check_arg, const LEX_CSTRING *field_name_arg);
+  enum ha_base_keytype key_type() const override { return HA_KEYTYPE_BINARY; }
+  uint size_of() const override { return sizeof *this; }
+  int store(const char *to, size_t length, CHARSET_INFO *charset) override;
+  int store(double nr) override { return Field_bit::store(nr); }
+  int store(longlong nr, bool unsigned_val) override
+  { return Field_bit::store(nr, unsigned_val); }
+  void sql_type(String &str) const override;
+};
+
+
+class Field_row final :public Field_null
+{
+  class Virtual_tmp_table *m_table;
+public:
+  Field_row(uchar *ptr_arg, const LEX_CSTRING *field_name_arg)
+    :Field_null(ptr_arg, 0, Field::NONE, field_name_arg, &my_charset_bin),
+     m_table(NULL)
+    {}
+  ~Field_row();
+  en_fieldtype tmp_engine_column_type(bool use_packed_rows) const
+  {
+    DBUG_ASSERT(0);
+    return Field::tmp_engine_column_type(use_packed_rows);
+  }
+  enum_conv_type rpl_conv_type_from(const Conv_source &source,
+                                    const Relay_log_info *rli,
+                                    const Conv_param &param) const
+  {
+    DBUG_ASSERT(0);
+    return CONV_TYPE_IMPOSSIBLE;
+  }
+  Virtual_tmp_table **virtual_tmp_table_addr() { return &m_table; }
+  bool sp_prepare_and_store_item(THD *thd, Item **value);
+};
+
+
+extern const LEX_CSTRING null_clex_str;
+
+class Column_definition_attributes
+{
+public:
+  /*
+    At various stages in execution this can be length of field in bytes or
+    max number of characters.
+  */
+  ulonglong length;
+  uint decimals;
+  Field::utype unireg_check;
+  const TYPELIB *interval;            // Which interval to use
+  CHARSET_INFO *charset;
+  uint32 srid;
+  uint pack_flag;
+  Column_definition_attributes()
+   :length(0),
+    decimals(0),
+    unireg_check(Field::NONE),
+    interval(NULL),
+    charset(&my_charset_bin),
+    srid(0),
+    pack_flag(0)
+  { }
+  Column_definition_attributes(const Field *field);
+  Column_definition_attributes(const Type_all_attributes &attr);
+  Field *make_field(TABLE_SHARE *share, MEM_ROOT *mem_root,
+                    const Record_addr *rec,
+                    const Type_handler *handler,
+                    const LEX_CSTRING *field_name,
+                    uint32 flags) const;
+  uint temporal_dec(uint intlen) const
+  {
+    return (uint) (length > intlen ? length - intlen - 1 : 0);
+  }
+  uint pack_flag_to_pack_length() const;
+  void frm_pack_basic(uchar *buff) const;
+  void frm_pack_charset(uchar *buff) const;
+  void frm_pack_numeric_with_dec(uchar *buff) const;
+  void frm_unpack_basic(const uchar *buff);
+  bool frm_unpack_charset(TABLE_SHARE *share, const uchar *buff);
+  bool frm_unpack_numeric_with_dec(TABLE_SHARE *share, const uchar *buff);
+  bool frm_unpack_temporal_with_dec(TABLE_SHARE *share, uint intlen,
+                                    const uchar *buff);
+  void set_length_and_dec(const Lex_length_and_dec_st &attr);
+  CHARSET_INFO *explicit_or_derived_charset(const Column_derived_attributes
+                                                  *derived_attr) const
+  {
+    return charset ? charset : derived_attr->charset();
+  }
+};
+
+
+/*
+  Create field class for CREATE TABLE
+*/
+class Column_definition: public Sql_alloc,
+                         public Type_handler_hybrid_field_type,
+                         public Column_definition_attributes
+{
+  /**
+    Create "interval" from "interval_list".
+    @param mem_root                   - memory root to create the TYPELIB
+                                        instance and its values on
+    @param reuse_interval_list_values - determines if TYPELIB can reuse strings
+                                        from interval_list, or should always
+                                        allocate a copy on mem_root, even if
+                                        character set conversion is not needed
+    @retval false on success
+    @retval true  on error (bad values, or EOM)
+  */
+  bool create_interval_from_interval_list(MEM_ROOT *mem_root,
+                                          bool reuse_interval_list_values);
+
+  /*
+    Calculate TYPELIB (set or enum) max and total lengths
+
+    @param  cs            charset+collation pair of the interval
+    @param  max_length    length of the longest item
+    @param  tot_length    sum of the item lengths
+
+    After this method call:
+    - ENUM uses max_length
+    - SET uses tot_length.
+  */
+  void calculate_interval_lengths(uint32 *max_length, uint32 *tot_length)
+  {
+    const char **pos;
+    uint *len;
+    *max_length= *tot_length= 0;
+    for (pos= interval->type_names, len= interval->type_lengths;
+         *pos ; pos++, len++)
+    {
+      size_t length= charset->numchars(*pos, *pos + *len);
+      DBUG_ASSERT(length < UINT_MAX32);
+      *tot_length+= (uint) length;
+      set_if_bigger(*max_length, (uint32)length);
+    }
+  }
+  bool prepare_stage1_check_typelib_default();
+  bool prepare_stage1_convert_default(THD *, MEM_ROOT *, CHARSET_INFO *to);
+  const Type_handler *field_type() const; // Prevent using this
+  Compression_method *compression_method_ptr;
+public:
+  LEX_CSTRING field_name;
+  LEX_CSTRING comment;			// Comment for field
+  enum enum_column_versioning
+  {
+    VERSIONING_NOT_SET,
+    WITH_VERSIONING,
+    WITHOUT_VERSIONING
+  };
+  Item *on_update;		        // ON UPDATE NOW()
+  field_visibility_t invisible;
+  /*
+    The value of `length' as set by parser: is the number of characters
+    for most of the types, or of bytes for BLOBs or numeric types.
+  */
+  uint32 char_length;
+  uint  flags, pack_length;
+  List<String> interval_list;
+  engine_option_value *option_list;
+
+
+  /*
+    This is additinal data provided for any computed(virtual) field.
+    In particular it includes a pointer to the item by  which this field
+    can be computed from other fields.
+  */
+  Virtual_column_info
+    *vcol_info,                      // Virtual field
+    *default_value,                  // Default value
+    *check_constraint;               // Check constraint
+
+  enum_column_versioning versioning;
+
+  Table_period_info *period;
+
+  Column_definition()
+   :Type_handler_hybrid_field_type(&type_handler_null),
+    compression_method_ptr(0),
+    comment(null_clex_str),
+    on_update(NULL), invisible(VISIBLE), char_length(0),
+    flags(0), pack_length(0),
+    option_list(NULL),
+    vcol_info(0), default_value(0), check_constraint(0),
+    versioning(VERSIONING_NOT_SET), period(NULL)
+  {
+    interval_list.empty();
+  }
+
+  Column_definition(THD *thd, Field *field, Field *orig_field);
+  bool set_attributes(THD *thd,
+                      const Lex_field_type_st &attr,
+                      CHARSET_INFO *cs,
+                      column_definition_type_t type);
+  void create_length_to_internal_length_null()
+  {
+    DBUG_ASSERT(length == 0);
+    pack_length= 0;
+  }
+  void create_length_to_internal_length_simple()
+  {
+    pack_length= type_handler()->calc_pack_length((uint32) length);
+  }
+  void create_length_to_internal_length_string()
+  {
+    length*= charset->mbmaxlen;
+    if (real_field_type() == MYSQL_TYPE_VARCHAR && compression_method())
+      length++;
+    set_if_smaller(length, UINT_MAX32);
+    pack_length= type_handler()->calc_pack_length((uint32) length);
+  }
+  void create_length_to_internal_length_typelib()
+  {
+    /* Pack_length already calculated in sql_parse.cc */
+    length*= charset->mbmaxlen;
+  }
+  bool vers_sys_field() const
+  {
+    return flags & (VERS_SYS_START_FLAG | VERS_SYS_END_FLAG);
+  }
+  void create_length_to_internal_length_bit();
+  void create_length_to_internal_length_newdecimal();
+
+  /*
+    Prepare the "charset" member for string data types,
+    such as CHAR, VARCHAR, TEXT, ENUM, SET:
+    - derive the charset if not specified explicitly
+    - find a _bin collation if the BINARY comparison style was specified, e.g.:
+       CREATE TABLE t1 (a VARCHAR(10) BINARY) CHARSET utf8;
+  */
+  bool prepare_charset_for_string(const Column_derived_attributes *dattr);
+
+  /**
+    Prepare a SET/ENUM field.
+    Create "interval" from "interval_list" if needed, and adjust "length".
+    @param mem_root                   - Memory root to allocate TYPELIB and
+                                        its values on
+    @param reuse_interval_list_values - determines if TYPELIB can reuse value
+                                        buffers from interval_list, or should
+                                        always allocate a copy on mem_root,
+                                        even if character set conversion
+                                        is not needed
+  */
+  bool prepare_interval_field(MEM_ROOT *mem_root,
+                              bool reuse_interval_list_values);
+
+  void prepare_interval_field_calc_length()
+  {
+    uint32 field_length, dummy;
+    if (real_field_type() == MYSQL_TYPE_SET)
+    {
+      calculate_interval_lengths(&dummy, &field_length);
+      length= field_length + (interval->count - 1);
+    }
+    else /* MYSQL_TYPE_ENUM */
+    {
+      calculate_interval_lengths(&field_length, &dummy);
+      length= field_length;
+    }
+    set_if_smaller(length, MAX_FIELD_WIDTH - 1);
+  }
+
+  bool prepare_blob_field(THD *thd);
+
+  bool sp_prepare_create_field(THD *thd, MEM_ROOT *mem_root);
+
+  bool prepare_stage1(THD *thd, MEM_ROOT *mem_root,
+                      handler *file, ulonglong table_flags,
+                      const Column_derived_attributes *derived_attr);
+  void prepare_stage1_simple(CHARSET_INFO *cs)
+  {
+    charset= cs;
+    create_length_to_internal_length_simple();
+  }
+  bool prepare_stage1_typelib(THD *thd, MEM_ROOT *mem_root,
+                              handler *file, ulonglong table_flags);
+  bool prepare_stage1_string(THD *thd, MEM_ROOT *mem_root,
+                             handler *file, ulonglong table_flags);
+  bool prepare_stage1_bit(THD *thd, MEM_ROOT *mem_root,
+                          handler *file, ulonglong table_flags);
+
+  bool bulk_alter(const Column_derived_attributes *derived_attr,
+                  const Column_bulk_alter_attributes *bulk_attr)
+  {
+    return type_handler()->Column_definition_bulk_alter(this,
+                                                        derived_attr,
+                                                        bulk_attr);
+  }
+  void redefine_stage1_common(const Column_definition *dup_field,
+                              const handler *file);
+  bool redefine_stage1(const Column_definition *dup_field, const handler *file)
+  {
+    const Type_handler *handler= dup_field->type_handler();
+    return handler->Column_definition_redefine_stage1(this, dup_field, file);
+  }
+  bool prepare_stage2(handler *handler, ulonglong table_flags);
+  bool prepare_stage2_blob(handler *handler,
+                           ulonglong table_flags, uint field_flags);
+  bool prepare_stage2_varchar(ulonglong table_flags);
+  bool prepare_stage2_typelib(const char *type_name, uint field_flags,
+                              uint *dup_val_count);
+  uint pack_flag_numeric() const;
+  uint sign_length() const { return flags & UNSIGNED_FLAG ? 0 : 1; }
+  bool check_length(uint mysql_errno, uint max_allowed_length) const;
+  bool fix_attributes_real(uint default_length);
+  bool fix_attributes_int(uint default_length);
+  bool fix_attributes_decimal();
+  bool fix_attributes_temporal_with_time(uint int_part_length);
+  bool fix_attributes_bit();
+
+  bool check(THD *thd);
+  bool validate_check_constraint(THD *thd);
+
+  bool stored_in_db() const { return !vcol_info || vcol_info->stored_in_db; }
+
+  ha_storage_media field_storage_type() const
+  {
+    return (ha_storage_media)
+      ((flags >> FIELD_FLAGS_STORAGE_MEDIA) & 3);
+  }
+
+  column_format_type column_format() const
+  {
+    return (column_format_type)
+      ((flags >> FIELD_FLAGS_COLUMN_FORMAT) & 3);
+  }
+
+  bool has_default_function() const
+  {
+    return unireg_check != Field::NONE;
+  }
+
+  Field *make_field(TABLE_SHARE *share, MEM_ROOT *mem_root,
+                    const Record_addr *addr,
+                    const LEX_CSTRING *field_name_arg) const
+  {
+    return Column_definition_attributes::make_field(share, mem_root, addr,
+                                                    type_handler(),
+                                                    field_name_arg, flags);
+  }
+  Field *make_field(TABLE_SHARE *share, MEM_ROOT *mem_root,
+                    const LEX_CSTRING *field_name_arg) const
+  {
+    Record_addr addr(true);
+    return make_field(share, mem_root, &addr, field_name_arg);
+  }
+  /* Return true if default is an expression that must be saved explicitely */
+  bool has_default_expression();
+
+  bool has_default_now_unireg_check() const
+  {
+    return unireg_check == Field::TIMESTAMP_DN_FIELD
+        || unireg_check == Field::TIMESTAMP_DNUN_FIELD;
+  }
+
+  void set_type(const Column_definition &other)
+  {
+    set_handler(other.type_handler());
+    length= other.length;
+    char_length= other.char_length;
+    decimals= other.decimals;
+    flags= other.flags;
+    pack_length= other.pack_length;
+    unireg_check= other.unireg_check;
+    interval= other.interval;
+    charset= other.charset;
+    srid= other.srid;
+    pack_flag= other.pack_flag;
+  }
+
+  // Replace the entire value by another definition
+  void set_column_definition(const Column_definition *def)
+  {
+    *this= *def;
+  }
+  bool set_compressed(const char *method);
+  bool set_compressed_deprecated(THD *thd, const char *method);
+  bool set_compressed_deprecated_column_attribute(THD *thd,
+                                                  const char *pos,
+                                                  const char *method);
+  void set_compression_method(Compression_method *compression_method_arg)
+  { compression_method_ptr= compression_method_arg; }
+  Compression_method *compression_method() const
+  { return compression_method_ptr; }
+
+  bool check_vcol_for_key(THD *thd) const;
+};
+
+
+/**
+  List of ROW element definitions, e.g.:
+    DECLARE a ROW(a INT,b VARCHAR(10))
+*/
+class Row_definition_list: public List<class Spvar_definition>
+{
+public:
+  inline bool eq_name(const Spvar_definition *def, const LEX_CSTRING *name) const;
+  /**
+    Find a ROW field by name.
+    @param [IN]  name   - the name
+    @param [OUT] offset - if the ROW field found, its offset it returned here
+    @retval NULL        - the ROW field was not found
+    @retval !NULL       - the pointer to the found ROW field
+  */
+  Spvar_definition *find_row_field_by_name(const LEX_CSTRING *name, uint *offset) const
+  {
+    // Cast-off the "const" qualifier
+    List_iterator<Spvar_definition> it(*((List<Spvar_definition>*)this));
+    Spvar_definition *def;
+    for (*offset= 0; (def= it++); (*offset)++)
+    {
+      if (eq_name(def, name))
+        return def;
+    }
+    return 0;
+  }
+  static Row_definition_list *make(MEM_ROOT *mem_root, Spvar_definition *var)
+  {
+    Row_definition_list *list;
+    if (!(list= new (mem_root) Row_definition_list()))
+      return NULL;
+    return list->push_back(var, mem_root) ? NULL : list;
+  }
+  bool append_uniq(MEM_ROOT *thd, Spvar_definition *var);
+  bool adjust_formal_params_to_actual_params(THD *thd, List<Item> *args);
+  bool adjust_formal_params_to_actual_params(THD *thd,
+                                             Item **args, uint arg_count);
+  bool resolve_type_refs(THD *);
+};
+
+/**
+  This class is used during a stored routine or a trigger execution,
+  at sp_rcontext::create() time.
+  Currently it can represent:
+  - variables with explicit data types:   DECLARE a INT;
+  - variables with data type references:  DECLARE a t1.a%TYPE;
+  - ROW type variables
+
+  Notes:
+  - Scalar variables have m_field_definitions==NULL.
+  - ROW variables are defined as having MYSQL_TYPE_NULL,
+    with a non-empty m_field_definitions.
+
+  Data type references to other object types will be added soon, e.g.:
+  - DECLARE a table_name%ROWTYPE;
+  - DECLARE a cursor_name%ROWTYPE;
+  - DECLARE a record_name%TYPE;
+  - DECLARE a variable_name%TYPE;
+*/
+class Spvar_definition: public Column_definition
+{
+  Qualified_column_ident *m_column_type_ref; // for %TYPE
+  Table_ident *m_table_rowtype_ref;          // for table%ROWTYPE
+  bool m_cursor_rowtype_ref;                       // for cursor%ROWTYPE
+  uint m_cursor_rowtype_offset;                    // for cursor%ROWTYPE
+  Row_definition_list *m_row_field_definitions;    // for ROW
+public:
+  Spvar_definition()
+   :m_column_type_ref(NULL),
+    m_table_rowtype_ref(NULL),
+    m_cursor_rowtype_ref(false),
+    m_cursor_rowtype_offset(0),
+    m_row_field_definitions(NULL)
+  { }
+  Spvar_definition(THD *thd, Field *field)
+   :Column_definition(thd, field, NULL),
+    m_column_type_ref(NULL),
+    m_table_rowtype_ref(NULL),
+    m_cursor_rowtype_ref(false),
+    m_cursor_rowtype_offset(0),
+    m_row_field_definitions(NULL)
+  { }
+  const Type_handler *type_handler() const
+  {
+    return Type_handler_hybrid_field_type::type_handler();
+  }
+  bool is_column_type_ref() const { return m_column_type_ref != 0; }
+  bool is_table_rowtype_ref() const { return m_table_rowtype_ref != 0; }
+  bool is_cursor_rowtype_ref() const { return m_cursor_rowtype_ref; }
+  bool is_explicit_data_type() const
+  {
+    return !is_column_type_ref() &&
+           !is_table_rowtype_ref() &&
+           !is_cursor_rowtype_ref();
+  }
+  Qualified_column_ident *column_type_ref() const
+  {
+    return m_column_type_ref;
+  }
+  void set_column_type_ref(Qualified_column_ident *ref)
+  {
+    m_column_type_ref= ref;
+  }
+
+  Table_ident *table_rowtype_ref() const
+  {
+    return m_table_rowtype_ref;
+  }
+  void set_table_rowtype_ref(Table_ident *ref)
+  {
+    DBUG_ASSERT(ref);
+    set_handler(&type_handler_row);
+    m_table_rowtype_ref= ref;
+  }
+
+  uint cursor_rowtype_offset() const
+  {
+    return m_cursor_rowtype_offset;
+  }
+  void set_cursor_rowtype_ref(uint offset)
+  {
+    set_handler(&type_handler_row);
+    m_cursor_rowtype_ref= true;
+    m_cursor_rowtype_offset= offset;
+  }
+
+  /*
+    Find a ROW field by name.
+    See Row_field_list::find_row_field_by_name() for details.
+  */
+  Spvar_definition *find_row_field_by_name(const LEX_CSTRING *name, uint *offset) const
+  {
+    DBUG_ASSERT(m_row_field_definitions);
+    return m_row_field_definitions->find_row_field_by_name(name, offset);
+  }
+  uint is_row() const
+  {
+    return m_row_field_definitions != NULL;
+  }
+  // Check if "this" defines a ROW variable with n elements
+  uint is_row(uint n) const
+  {
+    return m_row_field_definitions != NULL &&
+           m_row_field_definitions->elements == n;
+  }
+  Row_definition_list *row_field_definitions() const
+  {
+    return m_row_field_definitions;
+  }
+  void set_row_field_definitions(Row_definition_list *list)
+  {
+    DBUG_ASSERT(list);
+    set_handler(&type_handler_row);
+    m_row_field_definitions= list;
+  }
+
+};
+
+
+inline bool Row_definition_list::eq_name(const Spvar_definition *def,
+                                         const LEX_CSTRING *name) const
+{
+  return def->field_name.length == name->length && my_strcasecmp(system_charset_info, def->field_name.str, name->str) == 0;
+}
+
+
+class Create_field :public Column_definition
+{
+public:
+  LEX_CSTRING change;			// If done with alter table
+  LEX_CSTRING after;			// Put column after this one
+  Field *field;				// For alter table
+  const TYPELIB *save_interval;         // Temporary copy for the above
+                                        // Used only for UCS2 intervals
+
+  /** structure with parsed options (for comparing fields in ALTER TABLE) */
+  ha_field_option_struct *option_struct;
+  uint	offset;
+  uint8 interval_id;
+  bool create_if_not_exists;            // Used in ALTER TABLE IF NOT EXISTS
+
+  Create_field():
+    Column_definition(),
+    field(0), option_struct(NULL),
+    create_if_not_exists(false)
+  {
+    change= after= null_clex_str;
+  }
+  Create_field(THD *thd, Field *old_field, Field *orig_field):
+    Column_definition(thd, old_field, orig_field),
+    change(old_field->field_name),
+    field(old_field), option_struct(old_field->option_struct),
+    create_if_not_exists(false)
+  {
+    after= null_clex_str;
+  }
+  /* Used to make a clone of this object for ALTER/CREATE TABLE */
+  Create_field *clone(MEM_ROOT *mem_root) const;
+};
+
+
+/*
+  A class for sending info to the client
+*/
+
+class Send_field :public Sql_alloc,
+                  public Type_handler_hybrid_field_type,
+                  public Send_field_extended_metadata
+{
+public:
+  LEX_CSTRING db_name;
+  LEX_CSTRING table_name, org_table_name;
+  LEX_CSTRING col_name, org_col_name;
+  ulong length;
+  uint flags, decimals;
+  Send_field(Field *field)
+  {
+    field->make_send_field(this);
+    DBUG_ASSERT(table_name.str != 0);
+    normalize();
+  }
+  Send_field(THD *thd, Item *item);
+  Send_field(Field *field,
+             const LEX_CSTRING &db_name_arg,
+             const LEX_CSTRING &table_name_arg)
+   :Type_handler_hybrid_field_type(field->type_handler()),
+    db_name(db_name_arg),
+    table_name(table_name_arg),
+    org_table_name(table_name_arg),
+    col_name(field->field_name),
+    org_col_name(field->field_name),
+    length(field->field_length),
+    flags(field->table->maybe_null ?
+          (field->flags & ~NOT_NULL_FLAG) : field->flags),
+    decimals(field->decimals())
+  {
+    normalize();
+  }
+
+private:
+  void normalize()
+  {
+    /* limit number of decimals for float and double */
+    if (type_handler()->field_type() == MYSQL_TYPE_FLOAT ||
+        type_handler()->field_type() == MYSQL_TYPE_DOUBLE)
+      set_if_smaller(decimals, FLOATING_POINT_DECIMALS);
+  }
+public:
+  // This should move to Type_handler eventually
+  uint32 max_char_length(CHARSET_INFO *cs) const
+  {
+    return type_handler()->field_type() >= MYSQL_TYPE_TINY_BLOB &&
+           type_handler()->field_type() <= MYSQL_TYPE_BLOB
+      ? static_cast<uint32>(length / cs->mbminlen)
+      : static_cast<uint32>(length / cs->mbmaxlen);
+  }
+  uint32 max_octet_length(CHARSET_INFO *from, CHARSET_INFO *to) const
+  {
+    /*
+      For TEXT/BLOB columns, field_length describes the maximum data
+      length in bytes. There is no limit to the number of characters
+      that a TEXT column can store, as long as the data fits into
+      the designated space.
+      For the rest of textual columns, field_length is evaluated as
+      char_count * mbmaxlen, where character count is taken from the
+      definition of the column. In other words, the maximum number
+      of characters here is limited by the column definition.
+
+      When one has a LONG TEXT column with a single-byte
+      character set, and the connection character set is multi-byte, the
+      client may get fields longer than UINT_MAX32, due to
+      <character set column> -> <character set connection> conversion.
+      In that case column max length would not fit into the 4 bytes
+      reserved for it in the protocol. So we cut it here to UINT_MAX32.
+    */
+    return char_to_byte_length_safe(max_char_length(from), to->mbmaxlen);
+  }
+
+  // This should move to Type_handler eventually
+  bool is_sane_float() const
+  {
+    return (decimals <= FLOATING_POINT_DECIMALS ||
+            (type_handler()->field_type() != MYSQL_TYPE_FLOAT &&
+             type_handler()->field_type() != MYSQL_TYPE_DOUBLE));
+  }
+  bool is_sane_signess() const
+  {
+    if (type_handler() == type_handler()->type_handler_signed() &&
+        type_handler() == type_handler()->type_handler_unsigned())
+      return true; // Any signess is allowed, e.g. DOUBLE, DECIMAL
+    /*
+      We are here e.g. in case of INT data type.
+      The UNSIGNED_FLAG bit must match in flags and in the type handler.
+    */
+    return ((bool) (flags & UNSIGNED_FLAG)) == type_handler()->is_unsigned();
+  }
+  bool is_sane() const
+  {
+    return is_sane_float() && is_sane_signess();
+  }
+};
+
+
+/*
+  A class for quick copying data to fields
+*/
+
+class Copy_field :public Sql_alloc {
+public:
+  uchar *from_ptr,*to_ptr;
+  uchar *from_null_ptr,*to_null_ptr;
+  bool *null_row;
+  uint	from_bit,to_bit;
+  /**
+    Number of bytes in the fields pointed to by 'from_ptr' and
+    'to_ptr'. Usually this is the number of bytes that are copied from
+    'from_ptr' to 'to_ptr'.
+
+    For variable-length fields (VARCHAR), the first byte(s) describe
+    the actual length of the text. For VARCHARs with length 
+       < 256 there is 1 length byte 
+       >= 256 there is 2 length bytes
+    Thus, if from_field is VARCHAR(10), from_length (and in most cases
+    to_length) is 11. For VARCHAR(1024), the length is 1026. @see
+    Field_varstring::length_bytes
+
+    Note that for VARCHARs, do_copy() will be do_varstring*() which
+    only copies the length-bytes (1 or 2) + the actual length of the
+    text instead of from/to_length bytes.
+  */
+  uint from_length,to_length;
+  Field *from_field,*to_field;
+  String tmp;					// For items
+
+  Copy_field() {}
+  ~Copy_field() {}
+  void set(Field *to,Field *from,bool save);	// Field to field 
+  void set(uchar *to,Field *from);		// Field to string
+  void (*do_copy)(Copy_field *);
+  void (*do_copy2)(Copy_field *);		// Used to handle null values
+};
+
+
+uint pack_length_to_packflag(uint type);
+enum_field_types get_blob_type_from_length(ulong length);
+int set_field_to_null(Field *field);
+int set_field_to_null_with_conversions(Field *field, bool no_conversions);
+int convert_null_to_field_value_or_error(Field *field);
+bool check_expression(Virtual_column_info *vcol, const LEX_CSTRING *name,
+                      enum_vcol_info_type type, Alter_info *alter_info= NULL);
+
+/*
+  The following are for the interface with the .frm file
+*/
+
+#define FIELDFLAG_DECIMAL		1U
+#define FIELDFLAG_BINARY		1U	// Shares same flag
+#define FIELDFLAG_NUMBER		2U
+#define FIELDFLAG_ZEROFILL		4U
+#define FIELDFLAG_PACK			120U	// Bits used for packing
+#define FIELDFLAG_INTERVAL		256U    // mangled with decimals!
+#define FIELDFLAG_BITFIELD		512U	// mangled with decimals!
+#define FIELDFLAG_BLOB			1024U	// mangled with decimals!
+#define FIELDFLAG_GEOM			2048U   // mangled with decimals!
+
+#define FIELDFLAG_TREAT_BIT_AS_CHAR     4096U   /* use Field_bit_as_char */
+#define FIELDFLAG_LONG_DECIMAL          8192U
+#define FIELDFLAG_NO_DEFAULT		16384U  /* sql */
+#define FIELDFLAG_MAYBE_NULL		32768U	// sql
+#define FIELDFLAG_HEX_ESCAPE		0x10000U
+#define FIELDFLAG_PACK_SHIFT		3
+#define FIELDFLAG_DEC_SHIFT		8
+#define FIELDFLAG_MAX_DEC               63U
+
+#define FIELDFLAG_DEC_MASK              0x3F00U
+
+#define MTYP_TYPENR(type) ((type) & 127U) // Remove bits from type
+
+#define f_is_dec(x)		((x) & FIELDFLAG_DECIMAL)
+#define f_is_num(x)		((x) & FIELDFLAG_NUMBER)
+#define f_is_zerofill(x)	((x) & FIELDFLAG_ZEROFILL)
+#define f_is_packed(x)		((x) & FIELDFLAG_PACK)
+#define f_packtype(x)		(((x) >> FIELDFLAG_PACK_SHIFT) & 15)
+#define f_decimals(x)		((uint8) (((x) >> FIELDFLAG_DEC_SHIFT) & FIELDFLAG_MAX_DEC))
+#define f_is_alpha(x)		(!f_is_num(x))
+#define f_is_binary(x)          ((x) & FIELDFLAG_BINARY) // 4.0- compatibility
+#define f_is_enum(x)            (((x) & (FIELDFLAG_INTERVAL | FIELDFLAG_NUMBER)) == FIELDFLAG_INTERVAL)
+#define f_is_bitfield(x)        (((x) & (FIELDFLAG_BITFIELD | FIELDFLAG_NUMBER)) == FIELDFLAG_BITFIELD)
+#define f_is_blob(x)		(((x) & (FIELDFLAG_BLOB | FIELDFLAG_NUMBER)) == FIELDFLAG_BLOB)
+#define f_is_geom(x)		(((x) & (FIELDFLAG_GEOM | FIELDFLAG_NUMBER)) == FIELDFLAG_GEOM)
+#define f_settype(x)		(((uint) (x)) << FIELDFLAG_PACK_SHIFT)
+#define f_maybe_null(x)		((x) & FIELDFLAG_MAYBE_NULL)
+#define f_no_default(x)		((x) & FIELDFLAG_NO_DEFAULT)
+#define f_bit_as_char(x)        ((x) & FIELDFLAG_TREAT_BIT_AS_CHAR)
+#define f_is_hex_escape(x)      ((x) & FIELDFLAG_HEX_ESCAPE)
+#define f_visibility(x)         (static_cast<field_visibility_t> ((x) & INVISIBLE_MAX_BITS))
+
+inline
+ulonglong TABLE::vers_end_id() const
+{
+  DBUG_ASSERT(versioned(VERS_TRX_ID));
+  return static_cast<ulonglong>(vers_end_field()->val_int());
+}
+
+inline
+ulonglong TABLE::vers_start_id() const
+{
+  DBUG_ASSERT(versioned(VERS_TRX_ID));
+  return static_cast<ulonglong>(vers_start_field()->val_int());
+}
+
+
+#endif /* FIELD_INCLUDED */