MySQL 9.1.0
Source Code Documentation
dict0stats.h
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28/** @file include/dict0stats.h
29 Code used for calculating and manipulating table statistics.
30
31 Created Jan 06, 2010 Vasil Dimov
32 *******************************************************/
33
34#ifndef dict0stats_h
35#define dict0stats_h
36
37#include "univ.i"
38
39#include "dict0types.h"
40#include "mem0mem.h"
41#include "trx0types.h"
42
44 DICT_STATS_RECALC_PERSISTENT, /* (re) calculate the
45 statistics using a precise and slow
46 algo and save them to the persistent
47 storage, if the persistent storage is
48 not present then emit a warning and
49 fall back to transient stats */
50 DICT_STATS_RECALC_TRANSIENT, /* (re) calculate the statistics
51 using an imprecise quick algo
52 without saving the results
53 persistently */
54 DICT_STATS_EMPTY_TABLE, /* Write all zeros (or 1 where it makes sense)
55 into a table and its indexes' statistics
56 members. The resulting stats correspond to an
57 empty table. If the table is using persistent
58 statistics, then they are saved on disk. */
60 from the persistent storage if the in-memory
61 structures have not been initialized yet,
62 otherwise do nothing */
63};
64
65/** Set the persistent statistics flag for a given table. This is set only in
66the in-memory table object and is not saved on disk. It will be read from the
67.frm file upon first open from MySQL after a server restart.
68@param[in,out] table table
69@param[in] ps_on persistent stats explicitly enabled
70@param[in] ps_off persistent stats explicitly disabled */
71static inline void dict_stats_set_persistent(dict_table_t *table, bool ps_on,
72 bool ps_off);
73
74/** Check whether persistent statistics is enabled for a given table.
75 @return true if enabled, false otherwise */
76[[nodiscard]] static inline bool dict_stats_is_persistent_enabled(
77 const dict_table_t *table); /*!< in: table */
78
79/** Set the auto recalc flag for a given table (only honored for a persistent
80stats enabled table). The flag is set only in the in-memory table object and is
81not saved in InnoDB files. It will be read from the .frm file upon first open
82from MySQL after a server restart.
83@param[in,out] table table
84@param[in] auto_recalc_on explicitly enabled
85@param[in] auto_recalc_off explicitly disabled */
87 bool auto_recalc_on,
88 bool auto_recalc_off);
89
90/** Check whether auto recalc is enabled for a given table.
91 @return true if enabled, false otherwise */
93 const dict_table_t *table); /*!< in: table */
94
95/** Initialize table's stats for the first time when opening a table. */
96static inline void dict_stats_init(dict_table_t *table); /*!< in/out: table */
97
98/** Deinitialize table's stats after the last close of the table. This is
99 used to detect "FLUSH TABLE" and refresh the stats upon next open. */
100static inline void dict_stats_deinit(dict_table_t *table); /*!< in/out: table */
101
102/** Calculates new estimates for table and index statistics. The statistics
103are used in query optimization.
104@param[in] table table for which statistics are to be updated.
105@param[in] stats_upd_option statistics update option (persistent, etc).
106@param[in] trx statistics update will be done as part of this transaction.
107 if null, a new transaction will be internally created.
108@return DB_* error code or DB_SUCCESS */
110 dict_stats_upd_option_t stats_upd_option,
111 trx_t *trx = nullptr);
112
113/** Removes the information for a particular index's stats from the persistent
114 storage if it exists and if there is data stored for this index.
115 This function creates its own trx and commits it.
116 @return DB_SUCCESS or error code */
118 const char *tname, /*!< in: table name */
119 const char *iname, /*!< in: index name */
120 char *errstr, /*!< out: error message if != DB_SUCCESS
121 is returned */
122 ulint errstr_sz); /*!< in: size of the errstr buffer */
123
124/** Removes the statistics for a table and all of its indexes from the
125 persistent storage if it exists and if there is data stored for the table.
126 This function creates its own transaction and commits it.
127 @return DB_SUCCESS or error code */
129 const char *table_name, /*!< in: table name */
130 char *errstr, /*!< out: error message
131 if != DB_SUCCESS is returned */
132 ulint errstr_sz); /*!< in: size of errstr buffer */
133
134/** Fetches or calculates new estimates for index statistics. */
135void dict_stats_update_for_index(dict_index_t *index); /*!< in/out: index */
136
137/** Renames a table in InnoDB persistent stats storage.
138 This function creates its own transaction and commits it.
139 @return DB_SUCCESS or error code */
140dberr_t dict_stats_rename_table(const char *old_name, /*!< in: old table name */
141 const char *new_name, /*!< in: new table name */
142 char *errstr, /*!< out: error string if !=
143 DB_SUCCESS is returned */
144 size_t errstr_sz); /*!< in: errstr size */
145
146/** Renames an index in InnoDB persistent stats storage.
147 This function creates its own transaction and commits it.
148 @return DB_SUCCESS or error code. DB_STATS_DO_NOT_EXIST will be returned
149 if the persistent stats do not exist. */
150[[nodiscard]] dberr_t dict_stats_rename_index(
151 const dict_table_t *table, /*!< in: table whose index
152 is renamed */
153 const char *old_index_name, /*!< in: old index name */
154 const char *new_index_name); /*!< in: new index name */
155
156/** Represent the record of innodb_table_stats table. */
158 public:
159 /** Constructor. */
161
162 /** Destructor. */
164
165 /** Set the data for the innodb_table_stats record.
166 @param[in] data data to be set in the record
167 @param[in] col_offset column offset
168 @param[in] len length of the data. */
169 void set_data(const byte *data, ulint col_offset, ulint len);
170
171 /** Get the table name from innodb_table_stats record.
172 @retval table name of the table_stats record. */
173 char *get_tbl_name() const;
174
175 /** Set the table name for the innodb_table_stats record.
176 @param[in] data data to be set in the record
177 @param[in] len length of the data. */
178 void set_tbl_name(const byte *data, ulint len);
179
180 /** Get the db name from the innodb_table_stats record.
181 @retval db name of the table stats record. */
182 char *get_db_name() const;
183
184 /** Set the db name for the innodb_table_stats record.
185 @param[in] data data to be set
186 @param[in] len length of the data. */
187 void set_db_name(const byte *data, ulint len);
188
189 /** Get the n_rows from the innodb_table_stats record.
190 @retval n_rows from the record. */
191 uint64_t get_n_rows() const;
192
193 /** Set the n_rows for the innodb_table_stats record.
194 @param[in] no_of_rows number of rows. */
195 void set_n_rows(uint64_t no_of_rows);
196
197 /** Get the clustered index size from
198 innodb_table_stats record.
199 @retval size of the clustered index. */
201
202 /** Set the clustered index size for the
203 innodb_table_stats record.
204 @param[in] clust_size clustered index size. */
205 void set_clustered_index_size(ulint clust_size);
206
207 /** Get the sum of other index size.
208 @retval sum of secondary index size. */
210
211 /** Set the sum of sec index size.
212 @param[in] sum_of_other_index_size sum of secondary index size. */
213 void set_sum_of_other_index_size(ulint sum_of_other_index_size);
214
215 /** Column number of innodb_table_stats.database_name. */
216 static constexpr unsigned DB_NAME_COL_NO = 0;
217 /** Column number of innodb_table_stats.table_name. */
218 static constexpr unsigned TABLE_NAME_COL_NO = 1;
219 /** Column number of innodb_table_stats.n_rows. */
220 static constexpr unsigned N_ROWS_COL_NO = 3;
221 /** Column number of innodb_table_stats.clustered_index_size. */
222 static constexpr unsigned CLUST_INDEX_SIZE_COL_NO = 4;
223 /** Column number of innodb_table_stats.sum_of_other_index_sizes. */
224 static constexpr unsigned SUM_OF_OTHER_INDEX_SIZE_COL_NO = 5;
225
226 private:
227 /** Database name. */
229 /** Table name. */
231 /** Number of rows. */
232 uint64_t m_n_rows;
233 /** Clustered index size. */
235 /** Sum of other index size. */
237 /** Heap to store db_name, tbl_name for the record. */
239};
240
241#include "dict0stats.ic"
242
243#ifdef UNIV_ENABLE_UNIT_TEST_DICT_STATS
244void test_dict_stats_all();
245#endif /* UNIV_ENABLE_UNIT_TEST_DICT_STATS */
246
247#endif /* dict0stats_h */
Represent the record of innodb_table_stats table.
Definition: dict0stats.h:157
ulint m_sum_of_other_index_sizes
Sum of other index size.
Definition: dict0stats.h:236
void set_db_name(const byte *data, ulint len)
Set the db name for the innodb_table_stats record.
Definition: dict0stats.cc:3499
void set_n_rows(uint64_t no_of_rows)
Set the n_rows for the innodb_table_stats record.
Definition: dict0stats.cc:3476
void set_clustered_index_size(ulint clust_size)
Set the clustered index size for the innodb_table_stats record.
Definition: dict0stats.cc:3484
char * m_tbl_name
Table name.
Definition: dict0stats.h:230
void set_data(const byte *data, ulint col_offset, ulint len)
Set the data for the innodb_table_stats record.
Definition: dict0stats.cc:3519
static constexpr unsigned CLUST_INDEX_SIZE_COL_NO
Column number of innodb_table_stats.clustered_index_size.
Definition: dict0stats.h:222
static constexpr unsigned DB_NAME_COL_NO
Column number of innodb_table_stats.database_name.
Definition: dict0stats.h:216
mem_heap_t * m_heap
Heap to store db_name, tbl_name for the record.
Definition: dict0stats.h:238
void set_tbl_name(const byte *data, ulint len)
Set the table name for the innodb_table_stats record.
Definition: dict0stats.cc:3510
ulint m_clustered_index_size
Clustered index size.
Definition: dict0stats.h:234
static constexpr unsigned TABLE_NAME_COL_NO
Column number of innodb_table_stats.table_name.
Definition: dict0stats.h:218
void set_sum_of_other_index_size(ulint sum_of_other_index_size)
Set the sum of sec index size.
Definition: dict0stats.cc:3492
static constexpr unsigned N_ROWS_COL_NO
Column number of innodb_table_stats.n_rows.
Definition: dict0stats.h:220
ulint get_sum_of_other_index_size() const
Get the sum of other index size.
Definition: dict0stats.cc:3488
char * get_db_name() const
Get the db name from the innodb_table_stats record.
Definition: dict0stats.cc:3497
TableStatsRecord()
Constructor.
Definition: dict0stats.cc:3466
~TableStatsRecord()
Destructor.
Definition: dict0stats.cc:3468
static constexpr unsigned SUM_OF_OTHER_INDEX_SIZE_COL_NO
Column number of innodb_table_stats.sum_of_other_index_sizes.
Definition: dict0stats.h:224
char * m_db_name
Database name.
Definition: dict0stats.h:228
char * get_tbl_name() const
Get the table name from innodb_table_stats record.
Definition: dict0stats.cc:3508
uint64_t m_n_rows
Number of rows.
Definition: dict0stats.h:232
uint64_t get_n_rows() const
Get the n_rows from the innodb_table_stats record.
Definition: dict0stats.cc:3474
ulint get_clustered_index_size() const
Get the clustered index size from innodb_table_stats record.
Definition: dict0stats.cc:3480
dberr_t
Definition: db0err.h:39
static bool dict_stats_auto_recalc_is_enabled(const dict_table_t *table)
Check whether auto recalc is enabled for a given table.
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.
Definition: dict0stats.cc:2829
static void dict_stats_init(dict_table_t *table)
Initialize table's stats for the first time when opening a 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.
Definition: dict0stats.cc:3292
dict_stats_upd_option_t
Definition: dict0stats.h:43
@ DICT_STATS_RECALC_PERSISTENT
Definition: dict0stats.h:44
@ DICT_STATS_RECALC_TRANSIENT
Definition: dict0stats.h:50
@ DICT_STATS_FETCH_ONLY_IF_NOT_IN_MEMORY
Definition: dict0stats.h:59
@ DICT_STATS_EMPTY_TABLE
Definition: dict0stats.h:54
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 an...
Definition: dict0stats.cc:3138
void dict_stats_update_for_index(dict_index_t *index)
Fetches or calculates new estimates for index statistics.
Definition: dict0stats.cc:2809
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).
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 i...
Definition: dict0stats.cc:2999
static bool dict_stats_is_persistent_enabled(const dict_table_t *table)
Check whether persistent statistics is enabled for a given table.
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.
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.
Definition: dict0stats.cc:3423
static void dict_stats_deinit(dict_table_t *table)
Deinitialize table's stats after the last close of the table.
Code used for calculating and manipulating table statistics.
Data dictionary global types.
The memory management.
static PFS_engine_table_share_proxy table
Definition: pfs.cc:61
const char * table_name
Definition: rules_table_service.cc:56
Data structure for an index.
Definition: dict0mem.h:1041
Data structure for a database table.
Definition: dict0mem.h:1904
The info structure stored at the beginning of a heap block.
Definition: mem0mem.h:302
Definition: trx0trx.h:675
Transaction system global type definitions.
Version control for database, common definitions, and include files.
unsigned long int ulint
Definition: univ.i:406