1 /***************************************************************************** 2 3 Copyright (c) 2009, 2016, Oracle and/or its affiliates. All Rights Reserved. 4 5 This program is free software; you can redistribute it and/or modify 6 it under the terms of the GNU General Public License, version 2.0, 7 as published by the Free Software Foundation. 8 9 This program is also distributed with certain software (including 10 but not limited to OpenSSL) that is licensed under separate terms, 11 as designated in a particular file or component or in included license 12 documentation. The authors of MySQL hereby grant you an additional 13 permission to link the program and your derivative works with the 14 separately licensed software that they have included with MySQL. 15 16 This program is distributed in the hope that it will be useful, 17 but WITHOUT ANY WARRANTY; without even the implied warranty of 18 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 19 GNU General Public License, version 2.0, for more details. 20 21 You should have received a copy of the GNU General Public License along with 22 this program; if not, write to the Free Software Foundation, Inc., 23 51 Franklin Street, Suite 500, Boston, MA 02110-1335 USA 24 25 *****************************************************************************/ 26 27 /**************************************************//** 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 "db0err.h" 40 #include "dict0types.h" 41 #include "trx0types.h" 42 43 enum dict_stats_upd_option_t { 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. */ 59 DICT_STATS_FETCH_ONLY_IF_NOT_IN_MEMORY /* fetch the stats 60 from the persistent storage if the in-memory 61 structures have not been initialized yet, 62 otherwise do nothing */ 63 }; 64 65 /*********************************************************************//** 66 Calculates new estimates for table and index statistics. This function 67 is relatively quick and is used to calculate transient statistics that 68 are not saved on disk. 69 This was the only way to calculate statistics before the 70 Persistent Statistics feature was introduced. */ 71 UNIV_INTERN 72 void 73 dict_stats_update_transient( 74 /*========================*/ 75 dict_table_t* table); /*!< in/out: table */ 76 77 /*********************************************************************//** 78 Set the persistent statistics flag for a given table. This is set only 79 in the in-memory table object and is not saved on disk. It will be read 80 from the .frm file upon first open from MySQL after a server restart. */ 81 UNIV_INLINE 82 void 83 dict_stats_set_persistent( 84 /*======================*/ 85 dict_table_t* table, /*!< in/out: table */ 86 ibool ps_on, /*!< in: persistent stats explicitly enabled */ 87 ibool ps_off) /*!< in: persistent stats explicitly disabled */ 88 MY_ATTRIBUTE((nonnull)); 89 90 /*********************************************************************//** 91 Check whether persistent statistics is enabled for a given table. 92 @return TRUE if enabled, FALSE otherwise */ 93 UNIV_INLINE 94 ibool 95 dict_stats_is_persistent_enabled( 96 /*=============================*/ 97 const dict_table_t* table) /*!< in: table */ 98 MY_ATTRIBUTE((nonnull, warn_unused_result)); 99 100 /*********************************************************************//** 101 Set the auto recalc flag for a given table (only honored for a persistent 102 stats enabled table). The flag is set only in the in-memory table object 103 and is not saved in InnoDB files. It will be read from the .frm file upon 104 first open from MySQL after a server restart. */ 105 UNIV_INLINE 106 void 107 dict_stats_auto_recalc_set( 108 /*=======================*/ 109 dict_table_t* table, /*!< in/out: table */ 110 ibool auto_recalc_on, /*!< in: explicitly enabled */ 111 ibool auto_recalc_off); /*!< in: explicitly disabled */ 112 113 /*********************************************************************//** 114 Check whether auto recalc is enabled for a given table. 115 @return TRUE if enabled, FALSE otherwise */ 116 UNIV_INLINE 117 ibool 118 dict_stats_auto_recalc_is_enabled( 119 /*==============================*/ 120 const dict_table_t* table); /*!< in: table */ 121 122 /*********************************************************************//** 123 Initialize table's stats for the first time when opening a table. */ 124 UNIV_INLINE 125 void 126 dict_stats_init( 127 /*============*/ 128 dict_table_t* table); /*!< in/out: table */ 129 130 /*********************************************************************//** 131 Deinitialize table's stats after the last close of the table. This is 132 used to detect "FLUSH TABLE" and refresh the stats upon next open. */ 133 UNIV_INLINE 134 void 135 dict_stats_deinit( 136 /*==============*/ 137 dict_table_t* table) /*!< in/out: table */ 138 MY_ATTRIBUTE((nonnull)); 139 140 /*********************************************************************//** 141 Calculates new estimates for table and index statistics. The statistics 142 are used in query optimization. 143 @return DB_* error code or DB_SUCCESS */ 144 UNIV_INTERN 145 dberr_t 146 dict_stats_update( 147 /*==============*/ 148 dict_table_t* table, /*!< in/out: table */ 149 dict_stats_upd_option_t stats_upd_option); 150 /*!< in: whether to (re) calc 151 the stats or to fetch them from 152 the persistent storage */ 153 154 /*********************************************************************//** 155 Removes the information for a particular index's stats from the persistent 156 storage if it exists and if there is data stored for this index. 157 This function creates its own trx and commits it. 158 @return DB_SUCCESS or error code */ 159 UNIV_INTERN 160 dberr_t 161 dict_stats_drop_index( 162 /*==================*/ 163 const char* tname, /*!< in: table name */ 164 const char* iname, /*!< in: index name */ 165 char* errstr, /*!< out: error message if != DB_SUCCESS 166 is returned */ 167 ulint errstr_sz);/*!< in: size of the errstr buffer */ 168 169 /*********************************************************************//** 170 Removes the statistics for a table and all of its indexes from the 171 persistent storage if it exists and if there is data stored for the table. 172 This function creates its own transaction and commits it. 173 @return DB_SUCCESS or error code */ 174 UNIV_INTERN 175 dberr_t 176 dict_stats_drop_table( 177 /*==================*/ 178 const char* table_name, /*!< in: table name */ 179 char* errstr, /*!< out: error message 180 if != DB_SUCCESS is returned */ 181 ulint errstr_sz); /*!< in: size of errstr buffer */ 182 183 /*********************************************************************//** 184 Fetches or calculates new estimates for index statistics. */ 185 UNIV_INTERN 186 void 187 dict_stats_update_for_index( 188 /*========================*/ 189 dict_index_t* index) /*!< in/out: index */ 190 MY_ATTRIBUTE((nonnull)); 191 192 /*********************************************************************//** 193 Renames a table in InnoDB persistent stats storage. 194 This function creates its own transaction and commits it. 195 @return DB_SUCCESS or error code */ 196 UNIV_INTERN 197 dberr_t 198 dict_stats_rename_table( 199 /*====================*/ 200 const char* old_name, /*!< in: old table name */ 201 const char* new_name, /*!< in: new table name */ 202 char* errstr, /*!< out: error string if != DB_SUCCESS 203 is returned */ 204 size_t errstr_sz); /*!< in: errstr size */ 205 206 #ifndef UNIV_NONINL 207 #include "dict0stats.ic" 208 #endif 209 210 #endif /* dict0stats_h */ 211