Code used for calculating and manipulating table statistics. More...

#include "univ.i"
#include "dict0types.h"
#include "mem0mem.h"
#include "trx0types.h"
#include "dict0stats.ic"

Classes
class	TableStatsRecord
	Represent the record of innodb_table_stats table. More...

Enumerations
enum	dict_stats_upd_option_t { DICT_STATS_RECALC_PERSISTENT , DICT_STATS_RECALC_TRANSIENT , DICT_STATS_EMPTY_TABLE , DICT_STATS_FETCH_ONLY_IF_NOT_IN_MEMORY }

Functions
static void	dict_stats_set_persistent (dict_table_t *table, bool ps_on, bool ps_off)
	Set the persistent statistics flag for a given table. More...

static bool	dict_stats_is_persistent_enabled (const dict_table_t *table)
	Check whether persistent statistics is enabled for a given table. More...

static void	dict_stats_auto_recalc_set (dict_table_t *table, bool auto_recalc_on, bool auto_recalc_off)
	Set the auto recalc flag for a given table (only honored for a persistent stats enabled table). More...

static bool	dict_stats_auto_recalc_is_enabled (const dict_table_t *table)
	Check whether auto recalc is enabled for a given table. More...

static void	dict_stats_init (dict_table_t *table)
	Initialize table's stats for the first time when opening a table. More...

static void	dict_stats_deinit (dict_table_t *table)
	Deinitialize table's stats after the last close of the table. More...

dberr_t	dict_stats_update (dict_table_t table, dict_stats_upd_option_t stats_upd_option, trx_t trx=nullptr)
	Calculates new estimates for table and index statistics. More...

dberr_t	dict_stats_drop_index (const char tname, const char iname, char *errstr, ulint errstr_sz)
	Removes the information for a particular index's stats from the persistent storage if it exists and if there is data stored for this index. More...

dberr_t	dict_stats_drop_table (const char table_name, char errstr, ulint errstr_sz)
	Removes the statistics for a table and all of its indexes from the persistent storage if it exists and if there is data stored for the table. More...

void	dict_stats_update_for_index (dict_index_t *index)
	Fetches or calculates new estimates for index statistics. More...

dberr_t	dict_stats_rename_table (const char old_name, const char new_name, char *errstr, size_t errstr_sz)
	Renames a table in InnoDB persistent stats storage. More...

dberr_t	dict_stats_rename_index (const dict_table_t table, const char old_index_name, const char *new_index_name)
	Renames an index in InnoDB persistent stats storage. More...

Detailed Description

Code used for calculating and manipulating table statistics.

Created Jan 06, 2010 Vasil Dimov

Enumeration Type Documentation

◆ dict_stats_upd_option_t

enum dict_stats_upd_option_t

Enumerator
DICT_STATS_RECALC_PERSISTENT
DICT_STATS_RECALC_TRANSIENT
DICT_STATS_EMPTY_TABLE
DICT_STATS_FETCH_ONLY_IF_NOT_IN_MEMORY

Function Documentation

◆ dict_stats_auto_recalc_is_enabled()

static bool dict_stats_auto_recalc_is_enabled ( const dict_table_t * table )

inlinestatic

Check whether auto recalc is enabled for a given table.

Returns: true if enabled, false otherwise in: table

◆ dict_stats_auto_recalc_set()

static void dict_stats_auto_recalc_set	(	dict_table_t *	table,
		bool	auto_recalc_on,
		bool	auto_recalc_off
	)

inlinestatic

Set the auto recalc flag for a given table (only honored for a persistent stats enabled table).

The flag is set only in the in-memory table object and is not saved in InnoDB files. It will be read from the .frm file upon first open from MySQL after a server restart.

Parameters

[in,out]	table	table
[in]	auto_recalc_on	explicitly enabled
[in]	auto_recalc_off	explicitly disabled

◆ dict_stats_deinit()

static void dict_stats_deinit ( dict_table_t * table )

inlinestatic

Deinitialize table's stats after the last close of the table.

This is used to detect "FLUSH TABLE" and refresh the stats upon next open. in/out: table

◆ dict_stats_drop_index()

dberr_t dict_stats_drop_index	(	const char *	db_and_table,
		const char *	iname,
		char *	errstr,
		ulint	errstr_sz
	)

Removes the information for a particular index's stats from the persistent storage if it exists and if there is data stored for this index.

This function creates its own trx and commits it.

Returns: DB_SUCCESS or error code in: size of the errstr buffer

This function creates its own trx and commits it. A note from Marko why we cannot edit user and sys_* tables in one trx: marko: The problem is that ibuf merges should be disabled while we are rolling back dict transactions. marko: If ibuf merges are not disabled, we need to scan the *.ibd files. But we shouldn't open *.ibd files before we have rolled back dict transactions and opened the SYS_* records for the *.ibd files.

Returns: DB_SUCCESS or error code

Parameters

db_and_table	in: db and table, e.g. 'db/table'
iname	in: index name
errstr	out: error message if != DB_SUCCESS is returned
errstr_sz	in: size of the errstr buffer

◆ dict_stats_drop_table()

dberr_t dict_stats_drop_table	(	const char *	db_and_table,
		char *	errstr,
		ulint	errstr_sz
	)

Removes the statistics for a table and all of its indexes from the persistent storage if it exists and if there is data stored for the table.

This function creates its own transaction and commits it.

Returns: DB_SUCCESS or error code in: size of errstr buffer

Removes the statistics for a table and all of its indexes from the persistent storage if it exists and if there is data stored for the table.

This function creates its own transaction and commits it.

Returns: DB_SUCCESS or error code

Parameters

db_and_table	in: db and table, e.g. 'db/table'
errstr	out: error message if != DB_SUCCESS is returned
errstr_sz	in: size of errstr buffer

◆ dict_stats_init()

static void dict_stats_init ( dict_table_t * table )

inlinestatic

Initialize table's stats for the first time when opening a table.

in/out: table

◆ dict_stats_is_persistent_enabled()

static bool dict_stats_is_persistent_enabled ( const dict_table_t * table )

inlinestatic

Check whether persistent statistics is enabled for a given table.

Returns: true if enabled, false otherwise in: table

◆ dict_stats_rename_index()

dberr_t dict_stats_rename_index	(	const dict_table_t *	table,
		const char *	old_index_name,
		const char *	new_index_name
	)

Renames an index in InnoDB persistent stats storage.

This function creates its own transaction and commits it.

Returns: DB_SUCCESS or error code. DB_STATS_DO_NOT_EXIST will be returned if the persistent stats do not exist. in: new index name

This function creates its own transaction and commits it.

Returns: DB_SUCCESS or error code. DB_STATS_DO_NOT_EXIST will be returned if the persistent stats do not exist.

Parameters

table	in: table whose index is renamed
old_index_name	in: old index name
new_index_name	in: new index name

◆ dict_stats_rename_table()

dberr_t dict_stats_rename_table	(	const char *	old_name,
		const char *	new_name,
		char *	errstr,
		size_t	errstr_sz
	)

Renames a table in InnoDB persistent stats storage.

This function creates its own transaction and commits it.

Returns: DB_SUCCESS or error code in: errstr size

This function creates its own transaction and commits it.

Returns: DB_SUCCESS or error code

Parameters

old_name	in: old name, e.g. 'db/table'
new_name	in: new name, e.g. 'db/table'
errstr	out: error string if != DB_SUCCESS is returned
errstr_sz	in: errstr size

◆ dict_stats_set_persistent()

static void dict_stats_set_persistent	(	dict_table_t *	table,
		bool	ps_on,
		bool	ps_off
	)

inlinestatic

Set the persistent statistics flag for a given table.

This is set only in the in-memory table object and is not saved on disk. It will be read from the .frm file upon first open from MySQL after a server restart.

Parameters

[in,out]	table	table
[in]	ps_on	persistent stats explicitly enabled
[in]	ps_off	persistent stats explicitly disabled

◆ dict_stats_update()

dberr_t dict_stats_update	(	dict_table_t *	table,
		dict_stats_upd_option_t	stats_upd_option,
		trx_t *	trx = `nullptr`
	)

Calculates new estimates for table and index statistics.

The statistics are used in query optimization.

Parameters

[in]	table	table for which statistics are to be updated.
[in]	stats_upd_option	statistics update option (persistent, etc).
[in]	trx	statistics update will be done as part of this transaction. if null, a new transaction will be internally created.

Returns: DB_* error code or DB_SUCCESS

◆ dict_stats_update_for_index()

void dict_stats_update_for_index ( dict_index_t * index )

Fetches or calculates new estimates for index statistics.

in/out: index

Parameters

index in/out: index

Classes

Enumerations

Functions

Detailed Description

Enumeration Type Documentation

◆ dict_stats_upd_option_t

Function Documentation

◆ dict_stats_auto_recalc_is_enabled()

◆ dict_stats_auto_recalc_set()

◆ dict_stats_deinit()

◆ dict_stats_drop_index()

◆ dict_stats_drop_table()

◆ dict_stats_init()

◆ dict_stats_is_persistent_enabled()

◆ dict_stats_rename_index()

◆ dict_stats_rename_table()

◆ dict_stats_set_persistent()

◆ dict_stats_update()

◆ dict_stats_update_for_index()