item_cmpfunc.h File Reference

#include <assert.h>
#include <sys/types.h>
#include <cstring>
#include <memory>
#include "field_types.h"
#include "my_alloc.h"
#include "my_compiler.h"
#include "my_inttypes.h"
#include "my_table_map.h"
#include "my_time.h"
#include "mysql/udf_registration_types.h"
#include "mysql_time.h"
#include "sql-common/my_decimal.h"
#include "sql/enum_query_type.h"
#include "sql/item.h"
#include "sql/item_func.h"
#include "sql/item_row.h"
#include "sql/mem_root_array.h"
#include "sql/parse_location.h"
#include "sql/sql_const.h"
#include "sql/sql_list.h"
#include "sql/table.h"
#include "sql_string.h"
#include "template_utils.h"

Go to the source code of this file.

Classes
class	HashJoinCondition
	A class that represents a join condition in a hash join. More...
class	Arg_comparator
class	Item_bool_func
class	Item_func_bool_const
	A predicate that is "always true" or "always false". More...
class	Item_func_true
	A predicate that is "always true". More...
class	Item_func_false
	A predicate that is "always false". More...
class	Item_func_truth
	Item class, to represent X IS [NOT] (TRUE | FALSE) boolean predicates. More...
class	Item_in_optimizer
class	Comp_creator
	Abstract factory interface for creating comparison predicates. More...
class	Linear_comp_creator
	Abstract base class for the comparison operators =, <> and <=>. More...
class	Eq_creator
class	Equal_creator
class	Ne_creator
class	Gt_creator
class	Lt_creator
class	Ge_creator
class	Le_creator
class	Item_bool_func2
	Base class for functions that usually take two arguments, which are possibly strings, and perform some kind of comparison on the two arguments and return a boolean. More...
class	Item_func_comparison
	Item_func_comparison is a class for comparison functions that take two arguments and return a boolean result. More...
class	Item_func_xor
	XOR inherits from Item_bool_func2 because it is not optimized yet. More...
class	Item_func_not
class	Item_func_match_predicate
	Wrapper class when MATCH function is used in WHERE clause. More...
class	Item_func_trig_cond
class	Item_func_not_all
class	Item_func_nop_all
class	Item_eq_base
	Base class for the equality comparison operators = and <=>. More...
class	Item_func_eq
	Implements the comparison operator equals (=) More...
class	Item_func_equal
	The <=> operator evaluates the same as. More...
class	Item_func_ge
	Implements the comparison operator greater than or equals (>=) More...
class	Item_func_gt
	Implements the comparison operator greater than (>) More...
class	Item_func_le
	Implements the comparison operator less than or equals (<=) More...
class	Item_func_reject_if
	Internal function used by subquery to derived transformation to check if a subquery is scalar. More...
class	Item_func_lt
	Implements the comparison operator less than (<) More...
class	Item_func_ne
	Implements the comparison operator not equals (<>) More...
class	Item_func_opt_neg
class	Item_func_between
class	Item_func_strcmp
struct	interval_range
class	Item_func_interval
class	Item_func_coalesce
class	Item_func_ifnull
class	Item_func_any_value
	ANY_VALUE(expr) is like expr except that it is not checked by aggregate_check logic. More...
class	Item_func_if
class	Item_func_nullif
class	in_vector
class	in_string
class	in_longlong
struct	in_longlong::packed_longlong
class	in_datetime_as_longlong
class	in_time_as_longlong
class	in_datetime
class	in_double
class	in_decimal
class	cmp_item
class	cmp_item_scalar
	cmp_item which stores a scalar (i.e. non-ROW). More...
class	cmp_item_string
class	cmp_item_json
class	cmp_item_int
class	cmp_item_datetime
class	cmp_item_real
class	cmp_item_decimal
class	Item_func_case
	CASE ... WHEN ... THEN ... END function implementation. More...
class	Item_func_in
	in_expr [NOT] IN (in_value_list). More...
class	cmp_item_row
class	in_row
class	Item_func_isnull
class	Item_is_not_null_test
class	Item_func_isnotnull
class	Item_func_like
class	Item_cond
class	Item_multi_eq
	The class Item_multi_eq is used to represent conjunctions of equality predicates of the form field1 = field2, and field = const in where conditions and on join conditions. More...
class	Item_multi_eq::FieldProxy
class	Item_multi_eq::ConstFieldProxy
struct	COND_EQUAL
class	Item_cond_and
class	Item_cond_or

Typedefs
typedef int(Arg_comparator::*	arg_cmp_func) ()

Functions
Item *	make_condition (Parse_context *pc, Item *item)
	Ensure that all expressions involved in conditions are boolean functions. More...
Item *	and_conds (Item *a, Item *b)
	Builds condition: (a AND b) IS TRUE. More...
longlong	get_datetime_value (THD *thd, Item ***item_arg, Item **, const Item *warn_item, bool *is_null)
	Retrieve correct DATETIME value from given item. More...
bool	get_mysql_time_from_str_no_warn (THD *thd, String *str, MYSQL_TIME *l_time, MYSQL_TIME_STATUS *status)
	A minion of get_mysql_time_from_str, see its description. More...
bool	get_mysql_time_from_str (THD *thd, String *str, enum_mysql_timestamp_type warn_type, const char *warn_name, MYSQL_TIME *l_time)
	Parse date provided in a string to a MYSQL_TIME. More...
void	find_and_adjust_equal_fields (Item *item, table_map available_tables, bool replace, bool *found)
bool	IsAnd (const Item *item)
	Returns true if the item is a conjunction. More...
template<class Func >
bool	WalkConjunction (Item *condition, Func func)
	Calls "func" on each term in "condition" if it's a conjunction (and recursively on any conjunction directly contained in it, thereby flattening nested AND structures). More...

Variables
static const int	UNKNOWN = -1
Eq_creator	eq_creator
Equal_creator	equal_creator
Ne_creator	ne_creator
Gt_creator	gt_creator
Lt_creator	lt_creator
Ge_creator	ge_creator
Le_creator	le_creator

Typedef Documentation

arg_cmp_func

typedef int(Arg_comparator::* arg_cmp_func) ()

Function Documentation

and_conds()

Item * and_conds ( Item *  a, Item *  b  )

inline

Builds condition: (a AND b) IS TRUE.

find_and_adjust_equal_fields()

void find_and_adjust_equal_fields	(	Item *	item,
		table_map	available_tables,
		bool	replace,
		bool *	found
	)

get_datetime_value()

longlong get_datetime_value	(	THD *	thd,
		Item ***	item_arg,
		Item **	,
		const Item *	warn_item,
		bool *	is_null
	)

Retrieve correct DATETIME value from given item.

Parameters

	thd	thread handle
	item_arg	item to retrieve DATETIME value from
	warn_item	item for issuing the conversion warning
[out]	is_null	true <=> the item_arg is null

Retrieves the correct DATETIME value from given item for comparison by the compare_datetime() function. If item's result can be compared as longlong then its int value is used and its string value is used otherwise. Strings are always parsed and converted to int values by the get_date_from_str() function. This allows us to compare correctly string dates with missed insignificant zeros. In order to compare correctly DATE and DATETIME items the result of the former are treated as a DATETIME with zero time (00:00:00).

Returns

the DATETIME value, all ones if Item is NULL

get_mysql_time_from_str()

bool get_mysql_time_from_str	(	THD *	thd,
		String *	str,
		enum_mysql_timestamp_type	warn_type,
		const char *	warn_name,
		MYSQL_TIME *	l_time
	)

Parse date provided in a string to a MYSQL_TIME.

Parameters

[in]	thd	Thread handle
[in]	str	A string to convert
[in]	warn_type	Type of the timestamp for issuing the warning
[in]	warn_name	Field name for issuing the warning
[out]	l_time	The MYSQL_TIME objects is initialized.

Parses a date provided in the string str into a MYSQL_TIME object. If the string contains an incorrect date or doesn't correspond to a date at all then a warning is issued. The warn_type and the warn_name arguments are used as the name and the type of the field when issuing the warning. If any input was discarded (trailing or non-timestamp-y characters), return value will be true.

Returns

Status flag

Return values

false	Success.
True	Indicates failure.

get_mysql_time_from_str_no_warn()

bool get_mysql_time_from_str_no_warn	(	THD *	thd,
		String *	str,
		MYSQL_TIME *	l_time,
		MYSQL_TIME_STATUS *	status
	)

A minion of get_mysql_time_from_str, see its description.

This version doesn't issue any warnings, leaving that to its parent. This method has one extra argument which return warnings.

Parameters

[in]	thd	Thread handle
[in]	str	A string to convert
[out]	l_time	The MYSQL_TIME objects is initialized.
[in,out]	status	Any warnings given are returned here

Returns

true if error

IsAnd()

bool IsAnd ( const Item *  item )

inline

Returns true if the item is a conjunction.

make_condition()

Item * make_condition	(	Parse_context *	pc,
		Item *	item
	)

Ensure that all expressions involved in conditions are boolean functions.

Specifically, change <non-bool-expr> to (0 <> <non-bool-expr>)

Parameters

pc	Parse context, including memroot for Item construction
item	Any expression, if not a boolean expression, convert it

Returns

= NULL Error <> NULL A boolean expression, possibly constructed as described above

Note

Due to the special conditions of a MATCH expression (it is both a function returning a floating point value and it may be used standalone in the WHERE clause), it is wrapped inside a special Item_func_match_predicate, instead of forming a non-equality.

WalkConjunction()

template<class Func >

bool WalkConjunction	(	Item *	condition,
		Func	func
	)

Calls "func" on each term in "condition" if it's a conjunction (and recursively on any conjunction directly contained in it, thereby flattening nested AND structures).

Otherwise, calls "func" on "condition". It aborts and returns true as soon as a call to "func" returns true.

Variable Documentation

eq_creator

Eq_creator eq_creator

extern

equal_creator

Equal_creator equal_creator

extern

ge_creator

Ge_creator ge_creator

extern

gt_creator

Gt_creator gt_creator

extern

le_creator

Le_creator le_creator

extern

lt_creator

Lt_creator lt_creator

extern

ne_creator

Ne_creator ne_creator

extern

UNKNOWN

const int UNKNOWN = -1

static