Index_lookup Struct Reference

Structure used for index-based lookups. More...

#include <sql_opt_exec_shared.h>

Public Member Functions
	Index_lookup ()
bool	impossible_null_ref () const
bool	has_guarded_conds () const
	Check if there are triggered/guarded conditions that might be 'switched off' by the subquery code when executing 'Full scan on NULL key' subqueries. More...

Public Attributes
bool	key_err
uint	key_parts
	num of ... More...
uint	key_length
	length of key_buff More...
int	key
	key no More...
uchar *	key_buff
	value to look for with key More...
uchar *	key_buff2
	key_buff+key_length More...
store_key **	key_copy
	Used to store the value from each keypart field. More...
Item **	items
	val()'s for each keypart More...
bool **	cond_guards
key_part_map	null_rejecting
table_map	depend_map
	Table depends on these tables. More...
uchar *	null_ref_key
ha_rows	use_count
bool	disable_cache
ulonglong *	keypart_hash = nullptr

Detailed Description

Structure used for index-based lookups.

Constructor & Destructor Documentation

Index_lookup()

Index_lookup::Index_lookup ( )

inline

Member Function Documentation

has_guarded_conds()

bool Index_lookup::has_guarded_conds ( ) const

inline

Check if there are triggered/guarded conditions that might be 'switched off' by the subquery code when executing 'Full scan on NULL key' subqueries.

Returns

true if there are guarded conditions, false otherwise

impossible_null_ref()

bool Index_lookup::impossible_null_ref ( ) const

inline

Returns

whether the reference contains NULL values which could never give a match.

Member Data Documentation

cond_guards

bool** Index_lookup::cond_guards

depend_map

table_map Index_lookup::depend_map

Table depends on these tables.

disable_cache

bool Index_lookup::disable_cache

items

Item** Index_lookup::items

val()'s for each keypart

key

int Index_lookup::key

key no

key_buff

uchar* Index_lookup::key_buff

value to look for with key

key_buff2

uchar* Index_lookup::key_buff2

key_buff+key_length

key_copy

store_key** Index_lookup::key_copy

Used to store the value from each keypart field.

These values are used for ref access. If key_copy[key_part] == NULL it means that the value is constant and does not need to be reevaluated

key_err

bool Index_lookup::key_err

key_length

uint Index_lookup::key_length

length of key_buff

key_parts

uint Index_lookup::key_parts

num of ...

keypart_hash

ulonglong* Index_lookup::keypart_hash = nullptr

null_ref_key

uchar* Index_lookup::null_ref_key

null_rejecting

key_part_map Index_lookup::null_rejecting

(null_rejecting & (1<<i)) 

means the condition is '=' and no matching rows will be produced if items[i] IS NULL (see add_not_null_conds())

use_count

ha_rows Index_lookup::use_count

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The documentation for this struct was generated from the following file:

• sql/sql_opt_exec_shared.h