Arg_comparator Class Reference

Inheritance diagram for Arg_comparator:

List of all members.

Public Member Functions
	Arg_comparator (Item **a1, Item **a2)
int	set_compare_func (Item_result_field *owner, Item_result type)
int	set_compare_func (Item_result_field *owner_arg)
int	set_cmp_func (Item_result_field *owner_arg, Item **a1, Item **a2, Item_result type)
int	set_cmp_func (Item_result_field *owner_arg, Item **a1, Item **a2, bool set_null_arg)
int	compare ()
int	compare_string ()
int	compare_binary_string ()
int	compare_real ()
int	compare_decimal ()
int	compare_int_signed ()
int	compare_int_signed_unsigned ()
int	compare_int_unsigned_signed ()
int	compare_int_unsigned ()
int	compare_time_packed ()
int	compare_e_time_packed ()
int	compare_row ()
int	compare_e_string ()
int	compare_e_binary_string ()
int	compare_e_real ()
int	compare_e_decimal ()
int	compare_e_int ()
int	compare_e_int_diff_signedness ()
int	compare_e_row ()
int	compare_real_fixed ()
int	compare_e_real_fixed ()
int	compare_datetime ()
Item **	cache_converted_constant (THD *thd, Item **value, Item **cache, Item_result type)
void	set_datetime_cmp_func (Item_result_field *owner_arg, Item **a1, Item **b1)
bool	is_owner_equal_func ()
void	cleanup ()
void	set_cmp_context_for_datetime ()
Static Public Member Functions
static bool	can_compare_as_dates (Item *a, Item *b, ulonglong *const_val_arg)
Public Attributes
DTCollation	cmp_collation
String	value1
String	value2
Static Public Attributes
static arg_cmp_func	comparator_matrix [5][2]
Friends
class	Item_func

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Member Function Documentation

Item ** Arg_comparator::cache_converted_constant	(	THD *	thd_arg,
		Item **	value,
		Item **	cache_item,
		Item_result	type
	)

Convert and cache a constant.

Parameters:

value	[in] An item to cache
cache_item	[out] Placeholder for the cache item
type	[in] Comparison type

When given item is a constant and its type differs from comparison type then cache its value to avoid type conversion of this constant on each evaluation. In this case the value is cached and the reference to the cache is returned. Original value is returned otherwise.

Returns:

cache item or original value.

int Arg_comparator::compare_binary_string

(

)

Compare strings byte by byte. End spaces are also compared.

Return values:

<0	*a < *b
0	*b == *b
>0	*a > *b

int Arg_comparator::compare_e_int_diff_signedness

(

)

Compare unsigned *a with signed *b or signed *a with unsigned *b.

int Arg_comparator::compare_e_string

(

)

Compare strings, but take into account that NULL == NULL.

int Arg_comparator::compare_e_time_packed

(

)

Compare arguments using numeric packed representation for '<=>'.

int Arg_comparator::compare_int_signed_unsigned

(

)

Compare signed (*a) with unsigned (*B)

int Arg_comparator::compare_int_unsigned

(

)

Compare values as BIGINT UNSIGNED.

int Arg_comparator::compare_int_unsigned_signed

(

)

Compare unsigned (*a) with signed (*B)

int Arg_comparator::compare_time_packed

(

)

Compare arguments using numeric packed temporal representation.

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Member Data Documentation

arg_cmp_func Arg_comparator::comparator_matrix [static]

Initial value:

{{&Arg_comparator::compare_string,     &Arg_comparator::compare_e_string},
 {&Arg_comparator::compare_real,       &Arg_comparator::compare_e_real},
 {&Arg_comparator::compare_int_signed, &Arg_comparator::compare_e_int},
 {&Arg_comparator::compare_row,        &Arg_comparator::compare_e_row},
 {&Arg_comparator::compare_decimal,    &Arg_comparator::compare_e_decimal}}

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The documentation for this class was generated from the following files:

• item_cmpfunc.h
• item_cmpfunc.cc
• mysqld.cc