MySQL 8.3.0
Source Code Documentation
dict0stats.h
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26
27/** @file include/dict0stats.h
28 Code used for calculating and manipulating table statistics.
29
30 Created Jan 06, 2010 Vasil Dimov
31 *******************************************************/
32
33#ifndef dict0stats_h
34#define dict0stats_h
35
36#include "univ.i"
37
38#include "dict0types.h"
39#include "mem0mem.h"
40#include "trx0types.h"
41
43 DICT_STATS_RECALC_PERSISTENT, /* (re) calculate the
44 statistics using a precise and slow
45 algo and save them to the persistent
46 storage, if the persistent storage is
47 not present then emit a warning and
48 fall back to transient stats */
49 DICT_STATS_RECALC_TRANSIENT, /* (re) calculate the statistics
50 using an imprecise quick algo
51 without saving the results
52 persistently */
53 DICT_STATS_EMPTY_TABLE, /* Write all zeros (or 1 where it makes sense)
54 into a table and its indexes' statistics
55 members. The resulting stats correspond to an
56 empty table. If the table is using persistent
57 statistics, then they are saved on disk. */
59 from the persistent storage if the in-memory
60 structures have not been initialized yet,
61 otherwise do nothing */
62};
63
64/** Set the persistent statistics flag for a given table. This is set only in
65the in-memory table object and is not saved on disk. It will be read from the
66.frm file upon first open from MySQL after a server restart.
67@param[in,out] table table
68@param[in] ps_on persistent stats explicitly enabled
69@param[in] ps_off persistent stats explicitly disabled */
70static inline void dict_stats_set_persistent(dict_table_t *table, bool ps_on,
71 bool ps_off);
72
73/** Check whether persistent statistics is enabled for a given table.
74 @return true if enabled, false otherwise */
75[[nodiscard]] static inline bool dict_stats_is_persistent_enabled(
76 const dict_table_t *table); /*!< in: table */
77
78/** Set the auto recalc flag for a given table (only honored for a persistent
79stats enabled table). The flag is set only in the in-memory table object and is
80not saved in InnoDB files. It will be read from the .frm file upon first open
81from MySQL after a server restart.
82@param[in,out] table table
83@param[in] auto_recalc_on explicitly enabled
84@param[in] auto_recalc_off explicitly disabled */
86 bool auto_recalc_on,
87 bool auto_recalc_off);
88
89/** Check whether auto recalc is enabled for a given table.
90 @return true if enabled, false otherwise */
92 const dict_table_t *table); /*!< in: table */
93
94/** Initialize table's stats for the first time when opening a table. */
95static inline void dict_stats_init(dict_table_t *table); /*!< in/out: table */
96
97/** Deinitialize table's stats after the last close of the table. This is
98 used to detect "FLUSH TABLE" and refresh the stats upon next open. */
99static inline void dict_stats_deinit(dict_table_t *table); /*!< in/out: table */
100
101/** Calculates new estimates for table and index statistics. The statistics
102are used in query optimization.
103@param[in] table table for which statistics are to be updated.
104@param[in] stats_upd_option statistics update option (persistent, etc).
105@param[in] trx statistics update will be done as part of this transaction.
106 if null, a new transaction will be internally created.
107@return DB_* error code or DB_SUCCESS */
109 dict_stats_upd_option_t stats_upd_option,
110 trx_t *trx = nullptr);
111
112/** Removes the information for a particular index's stats from the persistent
113 storage if it exists and if there is data stored for this index.
114 This function creates its own trx and commits it.
115 @return DB_SUCCESS or error code */
117 const char *tname, /*!< in: table name */
118 const char *iname, /*!< in: index name */
119 char *errstr, /*!< out: error message if != DB_SUCCESS
120 is returned */
121 ulint errstr_sz); /*!< in: size of the errstr buffer */
122
123/** Removes the statistics for a table and all of its indexes from the
124 persistent storage if it exists and if there is data stored for the table.
125 This function creates its own transaction and commits it.
126 @return DB_SUCCESS or error code */
128 const char *table_name, /*!< in: table name */
129 char *errstr, /*!< out: error message
130 if != DB_SUCCESS is returned */
131 ulint errstr_sz); /*!< in: size of errstr buffer */
132
133/** Fetches or calculates new estimates for index statistics. */
134void dict_stats_update_for_index(dict_index_t *index); /*!< in/out: index */
135
136/** Renames a table in InnoDB persistent stats storage.
137 This function creates its own transaction and commits it.
138 @return DB_SUCCESS or error code */
139dberr_t dict_stats_rename_table(const char *old_name, /*!< in: old table name */
140 const char *new_name, /*!< in: new table name */
141 char *errstr, /*!< out: error string if !=
142 DB_SUCCESS is returned */
143 size_t errstr_sz); /*!< in: errstr size */
144
145/** Renames an index in InnoDB persistent stats storage.
146 This function creates its own transaction and commits it.
147 @return DB_SUCCESS or error code. DB_STATS_DO_NOT_EXIST will be returned
148 if the persistent stats do not exist. */
149[[nodiscard]] dberr_t dict_stats_rename_index(
150 const dict_table_t *table, /*!< in: table whose index
151 is renamed */
152 const char *old_index_name, /*!< in: old index name */
153 const char *new_index_name); /*!< in: new index name */
154
155/** Evict the stats tables if they loaded in tablespace cache and also
156close the stats .ibd files. We have to close stats tables because
1578.0 stats tables will use the same name. We load the stats from 5.7
158with a suffix "_backup57" and migrate the statistics. */
160
161/** Represent the record of innodb_table_stats table. */
163 public:
164 /** Constructor. */
166
167 /** Destructor. */
169
170 /** Set the data for the innodb_table_stats record.
171 @param[in] data data to be set in the record
172 @param[in] col_offset column offset
173 @param[in] len length of the data. */
174 void set_data(const byte *data, ulint col_offset, ulint len);
175
176 /** Get the table name from innodb_table_stats record.
177 @retval table name of the table_stats record. */
178 char *get_tbl_name() const;
179
180 /** Set the table name for the innodb_table_stats record.
181 @param[in] data data to be set in the record
182 @param[in] len length of the data. */
183 void set_tbl_name(const byte *data, ulint len);
184
185 /** Get the db name from the innodb_table_stats record.
186 @retval db name of the table stats record. */
187 char *get_db_name() const;
188
189 /** Set the db name for the innodb_table_stats record.
190 @param[in] data data to be set
191 @param[in] len length of the data. */
192 void set_db_name(const byte *data, ulint len);
193
194 /** Get the n_rows from the innodb_table_stats record.
195 @retval n_rows from the record. */
196 uint64_t get_n_rows() const;
197
198 /** Set the n_rows for the innodb_table_stats record.
199 @param[in] no_of_rows number of rows. */
200 void set_n_rows(uint64_t no_of_rows);
201
202 /** Get the clustered index size from
203 innodb_table_stats record.
204 @retval size of the clustered index. */
206
207 /** Set the clustered index size for the
208 innodb_table_stats record.
209 @param[in] clust_size clustered index size. */
210 void set_clustered_index_size(ulint clust_size);
211
212 /** Get the sum of other index size.
213 @retval sum of secondary index size. */
215
216 /** Set the sum of sec index size.
217 @param[in] sum_of_other_index_size sum of secondary index size. */
218 void set_sum_of_other_index_size(ulint sum_of_other_index_size);
219
220 /** Column number of innodb_table_stats.database_name. */
221 static constexpr unsigned DB_NAME_COL_NO = 0;
222 /** Column number of innodb_table_stats.table_name. */
223 static constexpr unsigned TABLE_NAME_COL_NO = 1;
224 /** Column number of innodb_table_stats.n_rows. */
225 static constexpr unsigned N_ROWS_COL_NO = 3;
226 /** Column number of innodb_table_stats.clustered_index_size. */
227 static constexpr unsigned CLUST_INDEX_SIZE_COL_NO = 4;
228 /** Column number of innodb_table_stats.sum_of_other_index_sizes. */
229 static constexpr unsigned SUM_OF_OTHER_INDEX_SIZE_COL_NO = 5;
230
231 private:
232 /** Database name. */
234 /** Table name. */
236 /** Number of rows. */
237 uint64_t m_n_rows;
238 /** Clustered index size. */
240 /** Sum of other index size. */
242 /** Heap to store db_name, tbl_name for the record. */
244};
245
246#include "dict0stats.ic"
247
248#ifdef UNIV_ENABLE_UNIT_TEST_DICT_STATS
249void test_dict_stats_all();
250#endif /* UNIV_ENABLE_UNIT_TEST_DICT_STATS */
251
252#endif /* dict0stats_h */
Represent the record of innodb_table_stats table.
Definition: dict0stats.h:162
ulint m_sum_of_other_index_sizes
Sum of other index size.
Definition: dict0stats.h:241
void set_db_name(const byte *data, ulint len)
Set the db name for the innodb_table_stats record.
Definition: dict0stats.cc:3544
void set_n_rows(uint64_t no_of_rows)
Set the n_rows for the innodb_table_stats record.
Definition: dict0stats.cc:3521
void set_clustered_index_size(ulint clust_size)
Set the clustered index size for the innodb_table_stats record.
Definition: dict0stats.cc:3529
char * m_tbl_name
Table name.
Definition: dict0stats.h:235
void set_data(const byte *data, ulint col_offset, ulint len)
Set the data for the innodb_table_stats record.
Definition: dict0stats.cc:3564
static constexpr unsigned CLUST_INDEX_SIZE_COL_NO
Column number of innodb_table_stats.clustered_index_size.
Definition: dict0stats.h:227
static constexpr unsigned DB_NAME_COL_NO
Column number of innodb_table_stats.database_name.
Definition: dict0stats.h:221
mem_heap_t * m_heap
Heap to store db_name, tbl_name for the record.
Definition: dict0stats.h:243
void set_tbl_name(const byte *data, ulint len)
Set the table name for the innodb_table_stats record.
Definition: dict0stats.cc:3555
ulint m_clustered_index_size
Clustered index size.
Definition: dict0stats.h:239
static constexpr unsigned TABLE_NAME_COL_NO
Column number of innodb_table_stats.table_name.
Definition: dict0stats.h:223
void set_sum_of_other_index_size(ulint sum_of_other_index_size)
Set the sum of sec index size.
Definition: dict0stats.cc:3537
static constexpr unsigned N_ROWS_COL_NO
Column number of innodb_table_stats.n_rows.
Definition: dict0stats.h:225
ulint get_sum_of_other_index_size() const
Get the sum of other index size.
Definition: dict0stats.cc:3533
char * get_db_name() const
Get the db name from the innodb_table_stats record.
Definition: dict0stats.cc:3542
TableStatsRecord()
Constructor.
Definition: dict0stats.cc:3511
~TableStatsRecord()
Destructor.
Definition: dict0stats.cc:3513
static constexpr unsigned SUM_OF_OTHER_INDEX_SIZE_COL_NO
Column number of innodb_table_stats.sum_of_other_index_sizes.
Definition: dict0stats.h:229
char * m_db_name
Database name.
Definition: dict0stats.h:233
char * get_tbl_name() const
Get the table name from innodb_table_stats record.
Definition: dict0stats.cc:3553
uint64_t m_n_rows
Number of rows.
Definition: dict0stats.h:237
uint64_t get_n_rows() const
Get the n_rows from the innodb_table_stats record.
Definition: dict0stats.cc:3519
ulint get_clustered_index_size() const
Get the clustered index size from innodb_table_stats record.
Definition: dict0stats.cc:3525
dberr_t
Definition: db0err.h:38
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:2828
static void dict_stats_init(dict_table_t *table)
Initialize table's stats for the first time when opening a table.
void dict_stats_evict_tablespaces()
Evict the stats tables if they loaded in tablespace cache and also close the stats ....
Definition: dict0stats.cc:3469
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:3291
dict_stats_upd_option_t
Definition: dict0stats.h:42
@ DICT_STATS_RECALC_PERSISTENT
Definition: dict0stats.h:43
@ DICT_STATS_RECALC_TRANSIENT
Definition: dict0stats.h:49
@ DICT_STATS_FETCH_ONLY_IF_NOT_IN_MEMORY
Definition: dict0stats.h:58
@ DICT_STATS_EMPTY_TABLE
Definition: dict0stats.h:53
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:3137
void dict_stats_update_for_index(dict_index_t *index)
Fetches or calculates new estimates for index statistics.
Definition: dict0stats.cc:2808
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:2998
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:3422
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:60
const char * table_name
Definition: rules_table_service.cc:55
Data structure for an index.
Definition: dict0mem.h:1045
Data structure for a database table.
Definition: dict0mem.h:1908
The info structure stored at the beginning of a heap block.
Definition: mem0mem.h:301
Definition: trx0trx.h:683
Transaction system global type definitions.
Version control for database, common definitions, and include files.
unsigned long int ulint
Definition: univ.i:405