1 /***************************************************************************** 2 3 Copyright (c) 1996, 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/row0upd.h 29 Update of a row 30 31 Created 12/27/1996 Heikki Tuuri 32 *******************************************************/ 33 34 #ifndef row0upd_h 35 #define row0upd_h 36 37 #include "univ.i" 38 #include "data0data.h" 39 #include "row0types.h" 40 #include "btr0types.h" 41 #include "dict0types.h" 42 #include "trx0types.h" 43 44 #ifndef UNIV_HOTBACKUP 45 # include "btr0pcur.h" 46 # include "que0types.h" 47 # include "pars0types.h" 48 #endif /* !UNIV_HOTBACKUP */ 49 50 /*********************************************************************//** 51 Creates an update vector object. 52 @return own: update vector object */ 53 UNIV_INLINE 54 upd_t* 55 upd_create( 56 /*=======*/ 57 ulint n, /*!< in: number of fields */ 58 mem_heap_t* heap); /*!< in: heap from which memory allocated */ 59 /*********************************************************************//** 60 Returns the number of fields in the update vector == number of columns 61 to be updated by an update vector. 62 @return number of fields */ 63 UNIV_INLINE 64 ulint 65 upd_get_n_fields( 66 /*=============*/ 67 const upd_t* update); /*!< in: update vector */ 68 #ifdef UNIV_DEBUG 69 /*********************************************************************//** 70 Returns the nth field of an update vector. 71 @return update vector field */ 72 UNIV_INLINE 73 upd_field_t* 74 upd_get_nth_field( 75 /*==============*/ 76 const upd_t* update, /*!< in: update vector */ 77 ulint n); /*!< in: field position in update vector */ 78 #else 79 # define upd_get_nth_field(update, n) ((update)->fields + (n)) 80 #endif 81 #ifndef UNIV_HOTBACKUP 82 /*********************************************************************//** 83 Sets an index field number to be updated by an update vector field. */ 84 UNIV_INLINE 85 void 86 upd_field_set_field_no( 87 /*===================*/ 88 upd_field_t* upd_field, /*!< in: update vector field */ 89 ulint field_no, /*!< in: field number in a clustered 90 index */ 91 dict_index_t* index, /*!< in: index */ 92 trx_t* trx); /*!< in: transaction */ 93 /*********************************************************************//** 94 Returns a field of an update vector by field_no. 95 @return update vector field, or NULL */ 96 UNIV_INLINE 97 const upd_field_t* 98 upd_get_field_by_field_no( 99 /*======================*/ 100 const upd_t* update, /*!< in: update vector */ 101 ulint no) /*!< in: field_no */ 102 MY_ATTRIBUTE((nonnull, pure)); 103 /*********************************************************************//** 104 Writes into the redo log the values of trx id and roll ptr and enough info 105 to determine their positions within a clustered index record. 106 @return new pointer to mlog */ 107 UNIV_INTERN 108 byte* 109 row_upd_write_sys_vals_to_log( 110 /*==========================*/ 111 dict_index_t* index, /*!< in: clustered index */ 112 trx_id_t trx_id, /*!< in: transaction id */ 113 roll_ptr_t roll_ptr,/*!< in: roll ptr of the undo log record */ 114 byte* log_ptr,/*!< pointer to a buffer of size > 20 opened 115 in mlog */ 116 mtr_t* mtr); /*!< in: mtr */ 117 /*********************************************************************//** 118 Updates the trx id and roll ptr field in a clustered index record when 119 a row is updated or marked deleted. */ 120 UNIV_INLINE 121 void 122 row_upd_rec_sys_fields( 123 /*===================*/ 124 rec_t* rec, /*!< in/out: record */ 125 page_zip_des_t* page_zip,/*!< in/out: compressed page whose 126 uncompressed part will be updated, or NULL */ 127 dict_index_t* index, /*!< in: clustered index */ 128 const ulint* offsets,/*!< in: rec_get_offsets(rec, index) */ 129 const trx_t* trx, /*!< in: transaction */ 130 roll_ptr_t roll_ptr);/*!< in: roll ptr of the undo log record, 131 can be 0 during IMPORT */ 132 /*********************************************************************//** 133 Sets the trx id or roll ptr field of a clustered index entry. */ 134 UNIV_INTERN 135 void 136 row_upd_index_entry_sys_field( 137 /*==========================*/ 138 dtuple_t* entry, /*!< in/out: index entry, where the memory 139 buffers for sys fields are already allocated: 140 the function just copies the new values to 141 them */ 142 dict_index_t* index, /*!< in: clustered index */ 143 ulint type, /*!< in: DATA_TRX_ID or DATA_ROLL_PTR */ 144 ib_uint64_t val); /*!< in: value to write */ 145 /*********************************************************************//** 146 Creates an update node for a query graph. 147 @return own: update node */ 148 UNIV_INTERN 149 upd_node_t* 150 upd_node_create( 151 /*============*/ 152 mem_heap_t* heap); /*!< in: mem heap where created */ 153 /***********************************************************//** 154 Writes to the redo log the new values of the fields occurring in the index. */ 155 UNIV_INTERN 156 void 157 row_upd_index_write_log( 158 /*====================*/ 159 const upd_t* update, /*!< in: update vector */ 160 byte* log_ptr,/*!< in: pointer to mlog buffer: must 161 contain at least MLOG_BUF_MARGIN bytes 162 of free space; the buffer is closed 163 within this function */ 164 mtr_t* mtr); /*!< in: mtr into whose log to write */ 165 /***********************************************************//** 166 Returns TRUE if row update changes size of some field in index or if some 167 field to be updated is stored externally in rec or update. 168 @return TRUE if the update changes the size of some field in index or 169 the field is external in rec or update */ 170 UNIV_INTERN 171 ibool 172 row_upd_changes_field_size_or_external( 173 /*===================================*/ 174 dict_index_t* index, /*!< in: index */ 175 const ulint* offsets,/*!< in: rec_get_offsets(rec, index) */ 176 const upd_t* update);/*!< in: update vector */ 177 /***********************************************************//** 178 Returns true if row update contains disowned external fields. 179 @return true if the update contains disowned external fields. */ 180 UNIV_INTERN 181 bool 182 row_upd_changes_disowned_external( 183 /*==============================*/ 184 const upd_t* update) /*!< in: update vector */ 185 MY_ATTRIBUTE((nonnull, warn_unused_result)); 186 #endif /* !UNIV_HOTBACKUP */ 187 /***********************************************************//** 188 Replaces the new column values stored in the update vector to the 189 record given. No field size changes are allowed. This function is 190 usually invoked on a clustered index. The only use case for a 191 secondary index is row_ins_sec_index_entry_by_modify() or its 192 counterpart in ibuf_insert_to_index_page(). */ 193 UNIV_INTERN 194 void 195 row_upd_rec_in_place( 196 /*=================*/ 197 rec_t* rec, /*!< in/out: record where replaced */ 198 dict_index_t* index, /*!< in: the index the record belongs to */ 199 const ulint* offsets,/*!< in: array returned by rec_get_offsets() */ 200 const upd_t* update, /*!< in: update vector */ 201 page_zip_des_t* page_zip);/*!< in: compressed page with enough space 202 available, or NULL */ 203 #ifndef UNIV_HOTBACKUP 204 /***************************************************************//** 205 Builds an update vector from those fields which in a secondary index entry 206 differ from a record that has the equal ordering fields. NOTE: we compare 207 the fields as binary strings! 208 @return own: update vector of differing fields */ 209 UNIV_INTERN 210 upd_t* 211 row_upd_build_sec_rec_difference_binary( 212 /*====================================*/ 213 const rec_t* rec, /*!< in: secondary index record */ 214 dict_index_t* index, /*!< in: index */ 215 const ulint* offsets,/*!< in: rec_get_offsets(rec, index) */ 216 const dtuple_t* entry, /*!< in: entry to insert */ 217 mem_heap_t* heap) /*!< in: memory heap from which allocated */ 218 MY_ATTRIBUTE((warn_unused_result, nonnull)); 219 /***************************************************************//** 220 Builds an update vector from those fields, excluding the roll ptr and 221 trx id fields, which in an index entry differ from a record that has 222 the equal ordering fields. NOTE: we compare the fields as binary strings! 223 @return own: update vector of differing fields, excluding roll ptr and 224 trx id */ 225 UNIV_INTERN 226 const upd_t* 227 row_upd_build_difference_binary( 228 /*============================*/ 229 dict_index_t* index, /*!< in: clustered index */ 230 const dtuple_t* entry, /*!< in: entry to insert */ 231 const rec_t* rec, /*!< in: clustered index record */ 232 const ulint* offsets,/*!< in: rec_get_offsets(rec,index), or NULL */ 233 bool no_sys, /*!< in: skip the system columns 234 DB_TRX_ID and DB_ROLL_PTR */ 235 trx_t* trx, /*!< in: transaction (for diagnostics), 236 or NULL */ 237 mem_heap_t* heap) /*!< in: memory heap from which allocated */ 238 MY_ATTRIBUTE((nonnull(1,2,3,7), warn_unused_result)); 239 /***********************************************************//** 240 Replaces the new column values stored in the update vector to the index entry 241 given. */ 242 UNIV_INTERN 243 void 244 row_upd_index_replace_new_col_vals_index_pos( 245 /*=========================================*/ 246 dtuple_t* entry, /*!< in/out: index entry where replaced; 247 the clustered index record must be 248 covered by a lock or a page latch to 249 prevent deletion (rollback or purge) */ 250 dict_index_t* index, /*!< in: index; NOTE that this may also be a 251 non-clustered index */ 252 const upd_t* update, /*!< in: an update vector built for the index so 253 that the field number in an upd_field is the 254 index position */ 255 ibool order_only, 256 /*!< in: if TRUE, limit the replacement to 257 ordering fields of index; note that this 258 does not work for non-clustered indexes. */ 259 mem_heap_t* heap); /*!< in: memory heap for allocating and 260 copying the new values */ 261 /***********************************************************//** 262 Replaces the new column values stored in the update vector to the index entry 263 given. */ 264 UNIV_INTERN 265 void 266 row_upd_index_replace_new_col_vals( 267 /*===============================*/ 268 dtuple_t* entry, /*!< in/out: index entry where replaced; 269 the clustered index record must be 270 covered by a lock or a page latch to 271 prevent deletion (rollback or purge) */ 272 dict_index_t* index, /*!< in: index; NOTE that this may also be a 273 non-clustered index */ 274 const upd_t* update, /*!< in: an update vector built for the 275 CLUSTERED index so that the field number in 276 an upd_field is the clustered index position */ 277 mem_heap_t* heap) /*!< in: memory heap for allocating and 278 copying the new values */ 279 MY_ATTRIBUTE((nonnull)); 280 /***********************************************************//** 281 Replaces the new column values stored in the update vector. */ 282 UNIV_INTERN 283 void 284 row_upd_replace( 285 /*============*/ 286 dtuple_t* row, /*!< in/out: row where replaced, 287 indexed by col_no; 288 the clustered index record must be 289 covered by a lock or a page latch to 290 prevent deletion (rollback or purge) */ 291 row_ext_t** ext, /*!< out, own: NULL, or externally 292 stored column prefixes */ 293 const dict_index_t* index, /*!< in: clustered index */ 294 const upd_t* update, /*!< in: an update vector built for the 295 clustered index */ 296 mem_heap_t* heap); /*!< in: memory heap */ 297 /***********************************************************//** 298 Checks if an update vector changes an ordering field of an index record. 299 300 This function is fast if the update vector is short or the number of ordering 301 fields in the index is small. Otherwise, this can be quadratic. 302 NOTE: we compare the fields as binary strings! 303 @return TRUE if update vector changes an ordering field in the index record */ 304 UNIV_INTERN 305 ibool 306 row_upd_changes_ord_field_binary_func( 307 /*==================================*/ 308 dict_index_t* index, /*!< in: index of the record */ 309 const upd_t* update, /*!< in: update vector for the row; NOTE: the 310 field numbers in this MUST be clustered index 311 positions! */ 312 #ifdef UNIV_DEBUG 313 const que_thr_t*thr, /*!< in: query thread */ 314 #endif /* UNIV_DEBUG */ 315 const dtuple_t* row, /*!< in: old value of row, or NULL if the 316 row and the data values in update are not 317 known when this function is called, e.g., at 318 compile time */ 319 const row_ext_t*ext) /*!< NULL, or prefixes of the externally 320 stored columns in the old row */ 321 MY_ATTRIBUTE((warn_unused_result)); 322 #ifdef UNIV_DEBUG 323 # define row_upd_changes_ord_field_binary(index,update,thr,row,ext) \ 324 row_upd_changes_ord_field_binary_func(index,update,thr,row,ext) 325 #else /* UNIV_DEBUG */ 326 # define row_upd_changes_ord_field_binary(index,update,thr,row,ext) \ 327 row_upd_changes_ord_field_binary_func(index,update,row,ext) 328 #endif /* UNIV_DEBUG */ 329 /***********************************************************//** 330 Checks if an FTS indexed column is affected by an UPDATE. 331 @return offset within fts_t::indexes if FTS indexed column updated else 332 ULINT_UNDEFINED */ 333 UNIV_INTERN 334 ulint 335 row_upd_changes_fts_column( 336 /*=======================*/ 337 dict_table_t* table, /*!< in: table */ 338 upd_field_t* upd_field); /*!< in: field to check */ 339 /***********************************************************//** 340 Checks if an FTS Doc ID column is affected by an UPDATE. 341 @return whether Doc ID column is affected */ 342 UNIV_INTERN 343 bool 344 row_upd_changes_doc_id( 345 /*===================*/ 346 dict_table_t* table, /*!< in: table */ 347 upd_field_t* upd_field) /*!< in: field to check */ 348 MY_ATTRIBUTE((nonnull, warn_unused_result)); 349 /***********************************************************//** 350 Checks if an update vector changes an ordering field of an index record. 351 This function is fast if the update vector is short or the number of ordering 352 fields in the index is small. Otherwise, this can be quadratic. 353 NOTE: we compare the fields as binary strings! 354 @return TRUE if update vector may change an ordering field in an index 355 record */ 356 UNIV_INTERN 357 ibool 358 row_upd_changes_some_index_ord_field_binary( 359 /*========================================*/ 360 const dict_table_t* table, /*!< in: table */ 361 const upd_t* update);/*!< in: update vector for the row */ 362 /***********************************************************//** 363 Updates a row in a table. This is a high-level function used 364 in SQL execution graphs. 365 @return query thread to run next or NULL */ 366 UNIV_INTERN 367 que_thr_t* 368 row_upd_step( 369 /*=========*/ 370 que_thr_t* thr); /*!< in: query thread */ 371 #endif /* !UNIV_HOTBACKUP */ 372 /*********************************************************************//** 373 Parses the log data of system field values. 374 @return log data end or NULL */ 375 UNIV_INTERN 376 byte* 377 row_upd_parse_sys_vals( 378 /*===================*/ 379 byte* ptr, /*!< in: buffer */ 380 byte* end_ptr,/*!< in: buffer end */ 381 ulint* pos, /*!< out: TRX_ID position in record */ 382 trx_id_t* trx_id, /*!< out: trx id */ 383 roll_ptr_t* roll_ptr);/*!< out: roll ptr */ 384 /*********************************************************************//** 385 Updates the trx id and roll ptr field in a clustered index record in database 386 recovery. */ 387 UNIV_INTERN 388 void 389 row_upd_rec_sys_fields_in_recovery( 390 /*===============================*/ 391 rec_t* rec, /*!< in/out: record */ 392 page_zip_des_t* page_zip,/*!< in/out: compressed page, or NULL */ 393 const ulint* offsets,/*!< in: array returned by rec_get_offsets() */ 394 ulint pos, /*!< in: TRX_ID position in rec */ 395 trx_id_t trx_id, /*!< in: transaction id */ 396 roll_ptr_t roll_ptr);/*!< in: roll ptr of the undo log record */ 397 /*********************************************************************//** 398 Parses the log data written by row_upd_index_write_log. 399 @return log data end or NULL */ 400 UNIV_INTERN 401 byte* 402 row_upd_index_parse( 403 /*================*/ 404 byte* ptr, /*!< in: buffer */ 405 byte* end_ptr,/*!< in: buffer end */ 406 mem_heap_t* heap, /*!< in: memory heap where update vector is 407 built */ 408 upd_t** update_out);/*!< out: update vector */ 409 410 411 /* Update vector field */ 412 struct upd_field_t{ 413 unsigned field_no:16; /*!< field number in an index, usually 414 the clustered index, but in updating 415 a secondary index record in btr0cur.cc 416 this is the position in the secondary 417 index */ 418 #ifndef UNIV_HOTBACKUP 419 unsigned orig_len:16; /*!< original length of the locally 420 stored part of an externally stored 421 column, or 0 */ 422 que_node_t* exp; /*!< expression for calculating a new 423 value: it refers to column values and 424 constants in the symbol table of the 425 query graph */ 426 #endif /* !UNIV_HOTBACKUP */ 427 dfield_t new_val; /*!< new value for the column */ 428 }; 429 430 /* Update vector structure */ 431 struct upd_t{ 432 ulint info_bits; /*!< new value of info bits to record; 433 default is 0 */ 434 ulint n_fields; /*!< number of update fields */ 435 upd_field_t* fields; /*!< array of update fields */ 436 }; 437 438 #ifndef UNIV_HOTBACKUP 439 /* Update node structure which also implements the delete operation 440 of a row */ 441 442 struct upd_node_t{ 443 que_common_t common; /*!< node type: QUE_NODE_UPDATE */ 444 ibool is_delete;/* TRUE if delete, FALSE if update */ 445 ibool searched_update; 446 /* TRUE if searched update, FALSE if 447 positioned */ 448 ibool in_mysql_interface; 449 /* TRUE if the update node was created 450 for the MySQL interface */ 451 dict_foreign_t* foreign;/* NULL or pointer to a foreign key 452 constraint if this update node is used in 453 doing an ON DELETE or ON UPDATE operation */ 454 upd_node_t* cascade_node;/* NULL or an update node template which 455 is used to implement ON DELETE/UPDATE CASCADE 456 or ... SET NULL for foreign keys */ 457 mem_heap_t* cascade_heap;/* NULL or a mem heap where the cascade 458 node is created */ 459 sel_node_t* select; /*!< query graph subtree implementing a base 460 table cursor: the rows returned will be 461 updated */ 462 btr_pcur_t* pcur; /*!< persistent cursor placed on the clustered 463 index record which should be updated or 464 deleted; the cursor is stored in the graph 465 of 'select' field above, except in the case 466 of the MySQL interface */ 467 dict_table_t* table; /*!< table where updated */ 468 upd_t* update; /*!< update vector for the row */ 469 ulint update_n_fields; 470 /* when this struct is used to implement 471 a cascade operation for foreign keys, we store 472 here the size of the buffer allocated for use 473 as the update vector */ 474 sym_node_list_t columns;/* symbol table nodes for the columns 475 to retrieve from the table */ 476 ibool has_clust_rec_x_lock; 477 /* TRUE if the select which retrieves the 478 records to update already sets an x-lock on 479 the clustered record; note that it must always 480 set at least an s-lock */ 481 ulint cmpl_info;/* information extracted during query 482 compilation; speeds up execution: 483 UPD_NODE_NO_ORD_CHANGE and 484 UPD_NODE_NO_SIZE_CHANGE, ORed */ 485 /*----------------------*/ 486 /* Local storage for this graph node */ 487 ulint state; /*!< node execution state */ 488 dict_index_t* index; /*!< NULL, or the next index whose record should 489 be updated */ 490 dtuple_t* row; /*!< NULL, or a copy (also fields copied to 491 heap) of the row to update; this must be reset 492 to NULL after a successful update */ 493 row_ext_t* ext; /*!< NULL, or prefixes of the externally 494 stored columns in the old row */ 495 dtuple_t* upd_row;/* NULL, or a copy of the updated row */ 496 row_ext_t* upd_ext;/* NULL, or prefixes of the externally 497 stored columns in upd_row */ 498 mem_heap_t* heap; /*!< memory heap used as auxiliary storage; 499 this must be emptied after a successful 500 update */ 501 /*----------------------*/ 502 sym_node_t* table_sym;/* table node in symbol table */ 503 que_node_t* col_assign_list; 504 /* column assignment list */ 505 ulint magic_n; 506 }; 507 508 #define UPD_NODE_MAGIC_N 1579975 509 510 /* Node execution states */ 511 #define UPD_NODE_SET_IX_LOCK 1 /* execution came to the node from 512 a node above and if the field 513 has_clust_rec_x_lock is FALSE, we 514 should set an intention x-lock on 515 the table */ 516 #define UPD_NODE_UPDATE_CLUSTERED 2 /* clustered index record should be 517 updated */ 518 #define UPD_NODE_INSERT_CLUSTERED 3 /* clustered index record should be 519 inserted, old record is already delete 520 marked */ 521 #define UPD_NODE_INSERT_BLOB 4 /* clustered index record should be 522 inserted, old record is already 523 delete-marked; non-updated BLOBs 524 should be inherited by the new record 525 and disowned by the old record */ 526 #define UPD_NODE_UPDATE_ALL_SEC 5 /* an ordering field of the clustered 527 index record was changed, or this is 528 a delete operation: should update 529 all the secondary index records */ 530 #define UPD_NODE_UPDATE_SOME_SEC 6 /* secondary index entries should be 531 looked at and updated if an ordering 532 field changed */ 533 534 /* Compilation info flags: these must fit within 3 bits; see trx0rec.h */ 535 #define UPD_NODE_NO_ORD_CHANGE 1 /* no secondary index record will be 536 changed in the update and no ordering 537 field of the clustered index */ 538 #define UPD_NODE_NO_SIZE_CHANGE 2 /* no record field size will be 539 changed in the update */ 540 541 #endif /* !UNIV_HOTBACKUP */ 542 543 #ifndef UNIV_NONINL 544 #include "row0upd.ic" 545 #endif 546 547 #endif 548