field.cc File Reference

#include "sql/field.h"
#include <float.h>
#include <stddef.h>
#include <algorithm>
#include <cmath>
#include <memory>
#include <optional>
#include "decimal.h"
#include "my_alloc.h"
#include "my_byteorder.h"
#include "my_compare.h"
#include "my_compiler.h"
#include "my_dbug.h"
#include "my_double2ulonglong.h"
#include "my_sqlcommand.h"
#include "my_sys.h"
#include "my_time_t.h"
#include "myisampack.h"
#include "mysql/strings/dtoa.h"
#include "mysql/strings/int2str.h"
#include "mysql/strings/m_ctype.h"
#include "mysqld_error.h"
#include "scope_guard.h"
#include "sql-common/json_binary.h"
#include "sql-common/json_diff.h"
#include "sql-common/json_dom.h"
#include "sql-common/json_error_handler.h"
#include "sql-common/my_decimal.h"
#include "sql/create_field.h"
#include "sql/current_thd.h"
#include "sql/dd/cache/dictionary_client.h"
#include "sql/dd/types/table.h"
#include "sql/dd_table_share.h"
#include "sql/derror.h"
#include "sql/filesort.h"
#include "sql/gis/rtree_support.h"
#include "sql/gis/srid.h"
#include "sql/handler.h"
#include "sql/item.h"
#include "sql/item_json_func.h"
#include "sql/item_timefunc.h"
#include "sql/join_optimizer/bit_utils.h"
#include "sql/key.h"
#include "sql/log_event.h"
#include "sql/mysqld.h"
#include "sql/mysqld_cs.h"
#include "sql/protocol.h"
#include "sql/psi_memory_key.h"
#include "sql/spatial.h"
#include "sql/sql_class.h"
#include "sql/sql_exception_handler.h"
#include "sql/sql_lex.h"
#include "sql/sql_time.h"
#include "sql/sql_tmp_table.h"
#include "sql/srs_fetcher.h"
#include "sql/strfunc.h"
#include "sql/system_variables.h"
#include "sql/transaction_info.h"
#include "sql/tztime.h"
#include "sql_string.h"
#include "string_with_len.h"
#include "template_utils.h"
#include "typelib.h"

Classes
struct	Check_field_param

Namespaces
namespace	dd
	The version of the current data dictionary table definitions.
namespace	anonymous_namespace{field.cc}
	Function to compare two unsigned integers for their relative order.

Macros
#define	FLAGSTR(V, F)   ((V) & (F) ? #F " " : "")
#define	MAX_EXPONENT   1024
#define	DOUBLE_TO_STRING_CONVERSION_BUFFER_SIZE   FLOATING_POINT_BUFFER
#define	LONGLONG_TO_STRING_CONVERSION_BUFFER_SIZE   128
#define	DECIMAL_TO_STRING_CONVERSION_BUFFER_SIZE   128
#define	BLOB_PACK_LENGTH_TO_MAX_LENGH(arg)    ((ulong)((1LL << std::min(arg, 4U) * 8) - 1LL))
#define	FIELDTYPE_TEAR_FROM   (MYSQL_TYPE_BIT + 1)
#define	FIELDTYPE_TEAR_TO   (242 - 1)
#define	FIELDTYPE_NUM   (FIELDTYPE_TEAR_FROM + (255 - FIELDTYPE_TEAR_TO))

Functions
bool	anonymous_namespace{field.cc}::sql_type_prevents_inplace (const Field &from, const Create_field &to)
	Predicate to determine if a field type change prevents alter from being done inplace. More...
bool	anonymous_namespace{field.cc}::length_prevents_inplace (const Field &from, const Create_field &to)
	Predicate to determine if a length change prevents alter from being done inplace. More...
bool	anonymous_namespace{field.cc}::charset_prevents_inplace (const Field_str &from, const Create_field &to)
	Predicate to determine if a charset change prevents alter from being done inplace. More...
bool	anonymous_namespace{field.cc}::change_prevents_inplace (const Field_str &from, const Create_field &to)
	Predicate to determine if the difference between a Field and the new Create_field prevents alter from being done inplace. More...
int	field_type2index (enum_field_types field_type)
bool	pre_validate_value_generator_expr (Item *expression, const char *name, Value_generator_source source)
	Perform per item-type checks to determine if the expression is allowed for a generated column, default value expression, a functional index or a check constraint. More...
static Geometry::wkbType	geometry_type_to_wkb_type (Field::geometry_type t)
	Convert Field::geometry_type to the corresponding Geometry::wkbType. More...
static bool	test_if_important_data (const CHARSET_INFO *cs, const char *str, const char *strend)
int	anonymous_namespace{field.cc}::compare (unsigned int a, unsigned int b)
static void	push_numerical_conversion_warning (THD *thd, const char *str, uint length, const CHARSET_INFO *cs, const char *typestr, int error, const char *field_name="UNKNOWN", ulong row_num=0)
	Output a warning for erroneous conversion of strings to numerical values. More...
static void	set_decimal_warning (THD *thd, Field_new_decimal *field, int dec_error, my_decimal *dec_value, const char *from, size_t length, const CHARSET_INFO *charset_arg)
	Emits a warning for the decimal conversion error. More...
static size_t	field_well_formed_copy_nchars (const CHARSET_INFO *to_cs, char *to, size_t to_length, const CHARSET_INFO *from_cs, const char *from, size_t from_length, size_t nchars, const char **well_formed_error_pos, const char **cannot_convert_error_pos, const char **from_end_pos)
	Copy string with optional character set conversion. More...
static void	append_zerofill_and_unsigned (const Field_num *field, String *res)
	Appends the UNSIGNED and ZEROFILL attributes to a String if a Field_num has these attributes. More...
static void	integer_sql_type (const Field_num *field, const char *type_name, String *res)
	Writes an integer type specification to a string. More...
type_conversion_status	store_internal_with_error_check (Field_new_decimal *field, int err, my_decimal *value)
static int	my_datetime_number_to_str (char *pos, longlong tmp)
	Convert a number in format YYMMDDhhmmss to string. More...
static type_conversion_status	datetime_store_internal (TABLE *table, ulonglong tmp, uchar *ptr)
	Store a DATETIME in a 8-byte integer to record. More...
static longlong	datetime_get_internal (TABLE *table, uchar *ptr)
	Read a DATETIME from record to a 8-byte integer. More...
static void	store_blob_length (uchar *i_ptr, uint i_packlength, uint32 i_number)
static longlong	enum_val_int (const uchar *ptr, uint packlength, bool low_byte_first)
static bool	compare_type_names (const CHARSET_INFO *charset, TYPELIB *t1, TYPELIB *t2)
	Compare the first t1::count type names. More...
uint32	calc_key_length (enum_field_types sql_type, uint32 length, uint32 decimals, bool is_unsigned, uint32 elements)
	Calculate key length for field from its type, length and other attributes. More...
enum_field_types	get_blob_type_from_length (size_t length)
size_t	calc_pack_length (enum_field_types type, size_t length)
size_t	calc_pack_length (dd::enum_column_types type, size_t char_length, size_t elements_count, bool treat_bit_as_char, uint numeric_scale, bool is_unsigned)
	Calculate the length of the in-memory representation of the column from information which can be retrieved from dd::Column or Ha_fk_column_type describing it. More...
Field *	make_field (MEM_ROOT *mem_root, TABLE_SHARE *share, uchar *ptr, size_t field_length, uchar *null_pos, uchar null_bit, enum_field_types field_type, const CHARSET_INFO *field_charset, Field::geometry_type geom_type, uchar auto_flags, TYPELIB *interval, const char *field_name, bool is_nullable, bool is_zerofill, bool is_unsigned, uint decimals, bool treat_bit_as_char, uint pack_length_override, std::optional< gis::srid_t > srid, bool is_array)
	This function should only be called from legacy code. More...
Field *	make_field (const Create_field &create_field, TABLE_SHARE *share, const char *field_name, size_t field_length, uchar *ptr, uchar *null_pos, size_t null_bit)
	Instantiates a Field object with the given name and record buffer values. More...
Field *	make_field (const Create_field &create_field, TABLE_SHARE *share, uchar *ptr, uchar *null_pos, size_t null_bit)
	Instantiates a Field object with the given record buffer values. More...
Field *	make_field (const Create_field &create_field, TABLE_SHARE *share)
	Instantiates a Field object without a record buffer. More...
static void	handle_int16 (uchar *to, const uchar *from, size_t max_length, bool low_byte_first_from, bool low_byte_first_to)
static void	handle_int24 (uchar *to, const uchar *from, size_t max_length, bool low_byte_first_from, bool low_byte_first_to)
static void	handle_int32 (uchar *to, const uchar *from, size_t max_length, bool low_byte_first_from, bool low_byte_first_to)
static void	handle_int64 (uchar *to, const uchar *from, size_t max_length, bool low_byte_first_from, bool low_byte_first_to)
Create_field *	generate_create_field (THD *thd, Item *source_item, TABLE *tmp_table)
	Generate a Create_field from an Item. More...
const char *	get_field_name_or_expression (THD *thd, const Field *field)

Variables
const char	field_separator = ','
	Static variables. More...
static enum_field_types	field_types_merge_rules [FIELDTYPE_NUM][FIELDTYPE_NUM]
static Item_result	field_types_result_type [FIELDTYPE_NUM]

Macro Definition Documentation

BLOB_PACK_LENGTH_TO_MAX_LENGH

#define BLOB_PACK_LENGTH_TO_MAX_LENGH

(

arg

)

((ulong)((1LL << std::min(arg, 4U) * 8) - 1LL))

DECIMAL_TO_STRING_CONVERSION_BUFFER_SIZE

#define DECIMAL_TO_STRING_CONVERSION_BUFFER_SIZE   128

DOUBLE_TO_STRING_CONVERSION_BUFFER_SIZE

#define DOUBLE_TO_STRING_CONVERSION_BUFFER_SIZE   FLOATING_POINT_BUFFER

FIELDTYPE_NUM

#define FIELDTYPE_NUM   (FIELDTYPE_TEAR_FROM + (255 - FIELDTYPE_TEAR_TO))

FIELDTYPE_TEAR_FROM

#define FIELDTYPE_TEAR_FROM   (MYSQL_TYPE_BIT + 1)

FIELDTYPE_TEAR_TO

#define FIELDTYPE_TEAR_TO   (242 - 1)

FLAGSTR

#define FLAGSTR	(		V,
			F
	)		((V) & (F) ? #F " " : "")

LONGLONG_TO_STRING_CONVERSION_BUFFER_SIZE

#define LONGLONG_TO_STRING_CONVERSION_BUFFER_SIZE   128

MAX_EXPONENT

#define MAX_EXPONENT   1024

Function Documentation

append_zerofill_and_unsigned()

static void append_zerofill_and_unsigned ( const Field_num *  field, String *  res  )

static

Appends the UNSIGNED and ZEROFILL attributes to a String if a Field_num has these attributes.

Parameters

	field	the field with the attributes to append
[in,out]	res	the String to append to

calc_key_length()

uint32 calc_key_length	(	enum_field_types	sql_type,
		uint32	length,
		uint32	decimals,
		bool	is_unsigned,
		uint32	elements
	)

Calculate key length for field from its type, length and other attributes.

Note

for string fields "length" parameter is assumed to take into account character set.

TODO: Get rid of this function as its code is redundant with Field::key_length() code. However creation of Field object using make_field() just to call Field::key_length() is probably overkill.

calc_pack_length() [1/2]

size_t calc_pack_length	(	dd::enum_column_types	type,
		size_t	char_length,
		size_t	elements_count,
		bool	treat_bit_as_char,
		uint	numeric_scale,
		bool	is_unsigned
	)

Calculate the length of the in-memory representation of the column from information which can be retrieved from dd::Column or Ha_fk_column_type describing it.

This function calculates the amount of memory necessary to store values in the record buffer. It is used in cases when we want to calculate this value from the description of column in the form compatible with dd::Column without constructing full-blown Field object.

Note

The implementation is based on Create_field::init() and Create_field::create_length_to_internal_length().

Parameters

type	Column DD type.
char_length	Column length as stored in DD.
elements_count	Number of elements in column of ENUM/SET type.
treat_bit_as_char	Indicates whether this BIT column is represented as char column internally.
numeric_scale	Column numeric scale as stored in DD.
is_unsigned	Column unsignedness.

calc_pack_length() [2/2]

size_t calc_pack_length	(	enum_field_types	type,
		size_t	length
	)

compare_type_names()

static bool compare_type_names ( const CHARSET_INFO *  charset, TYPELIB *  t1, TYPELIB *  t2  )

static

Compare the first t1::count type names.

Returns

true if the type names of t1 match those of t2. false otherwise.

datetime_get_internal()

static longlong datetime_get_internal ( TABLE *  table, uchar *  ptr  )

inlinestatic

Read a DATETIME from record to a 8-byte integer.

Parameters

table	Table
ptr	Where to read from

Return values

An	integer in format YYYYMMDDhhmmss

datetime_store_internal()

static type_conversion_status datetime_store_internal ( TABLE *  table, ulonglong  tmp, uchar *  ptr  )

inlinestatic

Store a DATETIME in a 8-byte integer to record.

Parameters

table	Table
tmp	The number, in YYYYMMDDhhmmss format
ptr	Where to store to

enum_val_int()

static longlong enum_val_int ( const uchar *  ptr, uint  packlength, bool  low_byte_first  )

static

field_type2index()

int field_type2index ( enum_field_types  field_type )

inline

field_well_formed_copy_nchars()

static size_t field_well_formed_copy_nchars ( const CHARSET_INFO *  to_cs, char *  to, size_t  to_length, const CHARSET_INFO *  from_cs, const char *  from, size_t  from_length, size_t  nchars, const char **  well_formed_error_pos, const char **  cannot_convert_error_pos, const char **  from_end_pos  )

static

Copy string with optional character set conversion.

This calls helper function well_formed_copy_nchars to copy string with optional character set conversion. Specially, it checks if the ASCII code point exceeds code range. If YES, it allows the input but raises a warning.

Parameters

to_cs	Character set of "to" string
to	Store result here
to_length	Maximum length of "to" string
from_cs	From character set
from	Copy from here
from_length	Length of from string
nchars	Copy not more that nchars characters
well_formed_error_pos	Return position when "from" is not well formed or NULL otherwise.
cannot_convert_error_pos	Return position where a not convertible character met, or NULL otherwise.
from_end_pos	Return position where scanning of "from" string stopped.

Return values

length

of bytes copied to 'to'

generate_create_field()

Create_field * generate_create_field	(	THD *	thd,
		Item *	source_item,
		TABLE *	tmp_table
	)

Generate a Create_field from an Item.

This function generates a Create_field from an Item by first creating a temporary table Field from the Item, and then creating the Create_field from this Field (there is currently no way to go directly from Item to Create_field). It is used several places:

• In CREATE TABLE AS SELECT for creating the target table definition.
• In functional indexes for creating the hidden generated column from the indexed expression.

Parameters

thd	Thread handler
source_item	The item to generate a Create_field from
tmp_table	A table object which is used to generate a temporary table field, as described above. This doesn't need to be an existing table.

Returns

A Create_field generated from the input item, or nullptr in case of errors.

geometry_type_to_wkb_type()

static Geometry::wkbType geometry_type_to_wkb_type ( Field::geometry_type  t )

static

Convert Field::geometry_type to the corresponding Geometry::wkbType.

Parameters

t	The geometry_type to convert

Returns

The corresponding Geometry::wkbType, or Geometry::wkb_invalid_type if there's not suitable type.

get_blob_type_from_length()

enum_field_types get_blob_type_from_length

(

size_t

length

)

get_field_name_or_expression()

const char * get_field_name_or_expression	(	THD *	thd,
		const Field *	field
	)

Returns

the expression if the input field is a hidden generated column that represents a functional key part. If not, return the field name. In case of a functional index; the expression is allocated on the THD's MEM_ROOT.

handle_int16()

static void handle_int16 ( uchar *  to, const uchar *  from, size_t  max_length, bool  low_byte_first_from, bool  low_byte_first_to  )

inlinestatic

handle_int24()

static void handle_int24 ( uchar *  to, const uchar *  from, size_t  max_length, bool  low_byte_first_from, bool  low_byte_first_to  )

inlinestatic

handle_int32()

static void handle_int32 ( uchar *  to, const uchar *  from, size_t  max_length, bool  low_byte_first_from, bool  low_byte_first_to  )

inlinestatic

handle_int64()

static void handle_int64 ( uchar *  to, const uchar *  from, size_t  max_length, bool  low_byte_first_from, bool  low_byte_first_to  )

inlinestatic

integer_sql_type()

static void integer_sql_type ( const Field_num *  field, const char *  type_name, String *  res  )

static

Writes an integer type specification to a string.

make_field() [1/4]

Field * make_field	(	const Create_field &	create_field,
		TABLE_SHARE *	share
	)

Instantiates a Field object without a record buffer.

Parameters

create_field	The column meta data.
share	The table share object.

make_field() [2/4]

Field * make_field	(	const Create_field &	create_field,
		TABLE_SHARE *	share,
		const char *	field_name,
		size_t	field_length,
		uchar *	ptr,
		uchar *	null_pos,
		size_t	null_bit
	)

Instantiates a Field object with the given name and record buffer values.

Parameters

create_field	The column meta data.
share	The table share object.
field_name	Create_field::field_name is overridden with this value when instantiating the Field object.
field_length	Create_field::length is overridden with this value when instantiating the Field object.
ptr	The address of the data bytes.
null_pos	The address of the null bytes.
null_bit	The position of the column's null bit within the row's null bytes.

make_field() [3/4]

Field * make_field	(	const Create_field &	create_field,
		TABLE_SHARE *	share,
		uchar *	ptr,
		uchar *	null_pos,
		size_t	null_bit
	)

Instantiates a Field object with the given record buffer values.

Parameters

create_field	The column meta data.
share	The table share object.
ptr	The start of the record buffer.
null_pos	The address of the null bytes.
null_bit	The position of the column's null bit within the row's null bytes.

make_field() [4/4]

Field * make_field	(	MEM_ROOT *	mem_root,
		TABLE_SHARE *	share,
		uchar *	ptr,
		size_t	field_length,
		uchar *	null_pos,
		uchar	null_bit,
		enum_field_types	field_type,
		const CHARSET_INFO *	field_charset,
		Field::geometry_type	geom_type,
		uchar	auto_flags,
		TYPELIB *	interval,
		const char *	field_name,
		bool	is_nullable,
		bool	is_zerofill,
		bool	is_unsigned,
		uint	decimals,
		bool	treat_bit_as_char,
		uint	pack_length_override,
		std::optional< gis::srid_t >	srid,
		bool	is_array
	)

This function should only be called from legacy code.

my_datetime_number_to_str()

static int my_datetime_number_to_str ( char *  pos, longlong  tmp  )

inlinestatic

Convert a number in format YYMMDDhhmmss to string.

Straight coded to avoid problem with slow longlong arithmetic and sprintf.

Parameters

[out]	pos	pointer to convert to.
	tmp	number with datetime value.

pre_validate_value_generator_expr()

bool pre_validate_value_generator_expr	(	Item *	expression,
		const char *	name,
		Value_generator_source	source
	)

Perform per item-type checks to determine if the expression is allowed for a generated column, default value expression, a functional index or a check constraint.

Note that validation of the specific function is done later in procedures open_table_from_share and fix_value_generator_fields.

Parameters

expression	the expression to check for validity
name	used for error reporting
source	Source of value generator(a generated column, a regular column with generated default value or a check constraint).

Returns

false if ok, true otherwise

push_numerical_conversion_warning()

static void push_numerical_conversion_warning ( THD *  thd, const char *  str, uint  length, const CHARSET_INFO *  cs, const char *  typestr, int  error, const char *  field_name = "UNKNOWN", ulong  row_num = 0  )

static

Output a warning for erroneous conversion of strings to numerical values.

For use with ER_TRUNCATED_WRONG_VALUE[_FOR_FIELD]

Parameters

thd	THD object
str	pointer to string that failed to be converted
length	length of string
cs	charset for string
typestr	string describing type converted to
error	error value to output
field_name	(for *_FOR_FIELD) name of field
row_num	(for *_FOR_FIELD) row number

set_decimal_warning()

static void set_decimal_warning ( THD *  thd, Field_new_decimal *  field, int  dec_error, my_decimal *  dec_value, const char *  from, size_t  length, const CHARSET_INFO *  charset_arg  )

static

Emits a warning for the decimal conversion error.

May modify dec_value if there was conversion overflow or bad number.

Parameters

	thd	Thread handler
	field	Field to operate on
	dec_error	decimal library return code (E_DEC_* see include/decimal.h)
[in,out]	dec_value	Decimal value returned by conversion function.
	from	Value converted from
	length	Length of 'from'
	charset_arg	Charset of 'from'

store_blob_length()

static void store_blob_length ( uchar *  i_ptr, uint  i_packlength, uint32  i_number  )

static

store_internal_with_error_check()

type_conversion_status store_internal_with_error_check	(	Field_new_decimal *	field,
		int	err,
		my_decimal *	value
	)

test_if_important_data()

static bool test_if_important_data ( const CHARSET_INFO *  cs, const char *  str, const char *  strend  )

static

Variable Documentation

field_separator

const char field_separator = ','

Static variables.

field_types_merge_rules

enum_field_types field_types_merge_rules[FIELDTYPE_NUM][FIELDTYPE_NUM]

static

field_types_result_type

Item_result field_types_result_type[FIELDTYPE_NUM]

static