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d33b523271
Fixed BUGS: #3300: "UPDATE statement with no index column in where condition locks all rows" Implement semi-consistent read to reduce lock conflicts at the cost of breaking serializability. ha_innobase::unlock_row(): reset the "did semi consistent read" flag ha_innobase::was_semi_consistent_read(), ha_innobase::try_semi_consistent_read(): new methods row_prebuilt_t, row_create_prebuilt(): add field row_read_type for keeping track of semi-consistent reads row_vers_build_for_semi_consistent_read(), row_sel_build_committed_vers_for_mysql(): new functions row_search_for_mysql(): implement semi-consistent reads #9802: "Foreign key checks disallow alter table". Added test cases. #12456: "Cursor shows incorrect data - DML does not affect, probably caching" This patch implements a high-granularity read view to be used with cursors. In this high-granularity consistent read view modifications done by the creating transaction after the cursor is created or future transactions are not visible. But those modifications that transaction did before the cursor was created are visible. #12701: "Support >4GB buffer pool and log files on 64-bit Windows" Do not call os_file_create_tmpfile() at runtime. Instead, create all tempfiles at startup and guard access to them with mutexes. #13778: "If FOREIGN_KEY_CHECKS=0, one can create inconsistent FOREIGN KEYs". When FOREIGN_KEY_CHECKS=0 we still need to check that datatypes between foreign key references are compatible. #14189: "VARBINARY and BINARY variables: trailing space ignored with InnoDB" innobase_init(): Assert that DATA_MYSQL_BINARY_CHARSET_COLL == my_charset_bin.number. dtype_get_pad_char(): Do not pad VARBINARY or BINARY columns. row_ins_cascade_calc_update_vec(): Refuse ON UPDATE CASCADE when trying to change the length of a VARBINARY column that refers to or is referenced by a BINARY column. BINARY columns are no longer padded on comparison, and thus they cannot be padded on storage either. #14747: "Race condition can cause btr_search_drop_page_hash_index() to crash" Note that buf_block_t::index should be protected by btr_search_latch or an s-latch or x-latch on the index page. btr_search_drop_page_hash_index(): Read block->index while holding btr_search_latch and use the cached value in the loop. Remove some redundant assertions. #15108: "mysqld crashes when innodb_log_file_size is set > 4G" #15308: "Problem of Order with Enum Column in Primary Key" #15550: "mysqld crashes in printing a FOREIGN KEY error in InnoDB" row_ins_foreign_report_add_err(): When printing the parent record, use the index in the parent table rather than the index in the child table. #15653: "Slow inserts to InnoDB if many thousands of .ibd files" Keep track on unflushed modifications to file spaces. When there are tens of thousands of file spaces, flushing all files in fil_flush_file_spaces() would be very slow. fil_flush_file_spaces(): Only flush unflushed file spaces. fil_space_t, fil_system_t: Add a list of unflushed spaces. #15991: "innodb-file-per-table + symlink database + rename = cr" os_file_handle_error(): Map the error codes EXDEV, ENOTDIR, and EISDIR to the new code OS_FILE_PATH_ERROR. Treat this code as OS_FILE_PATH_ERROR. This fixes the crash on RENAME TABLE when the .ibd file is a symbolic link to a different file system. #16157: "InnoDB crashes when main location settings are empty" This patch is from Heikki. #16298: "InnoDB segfaults in INSERTs in upgrade of 4.0 -> 5.0 tables with VARCHAR BINARY" dict_load_columns(): Set the charset-collation code DATA_MYSQL_BINARY_CHARSET_COLL for those binary string columns that lack a charset-collation code, i.e., the tables were created with an older version of MySQL/InnoDB than 4.1.2. #16229: "MySQL/InnoDB uses full explicit table locks in trigger processing" Take a InnoDB table lock only if user has explicitly requested a table lock. Added some additional comments to store_lock() and external_lock(). #16387: "InnoDB crash when dropping a foreign key <table>_ibfk_0" Do not mistake TABLENAME_ibfk_0 for auto-generated id. dict_table_get_highest_foreign_id(): Ignore foreign constraint identifiers starting with the pattern TABLENAME_ibfk_0. #16582: "InnoDB: Error in an adaptive hash index pointer to page" Account for a race condition when dropping the adaptive hash index for a B-tree page. btr_search_drop_page_hash_index(): Retry the operation if a hash index with different parameters was built meanwhile. Add diagnostics for the case that hash node pointers to the page remain. btr_search_info_update_hash(), btr_search_info_update_slow(): Document the parameter "info" as in/out. #16814: "SHOW INNODB STATUS format error in LATEST FOREIGN KEY ERROR section" Add a missing newline to the LAST FOREIGN KEY ERROR section in SHOW INNODB STATUS output. dict_foreign_error_report(): Always print a newline after invoking dict_print_info_on_foreign_key_in_create_format(). #16827: "Better InnoDB error message if ibdata files omitted from my.cnf" #17126: "CHECK TABLE on InnoDB causes a short hang during check of adaptive hash" CHECK TABLE blocking other queries, by releasing the btr_search_latch periodically during the adaptive hash table validation. #17405: "Valgrind: conditional jump or move depends on unititialised values" buf_block_init(): Reset magic_n, buf_fix_count and io_fix to avoid testing uninitialized variables.
662 lines
19 KiB
C
662 lines
19 KiB
C
/******************************************************
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Row versions
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(c) 1997 Innobase Oy
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Created 2/6/1997 Heikki Tuuri
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*******************************************************/
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#include "row0vers.h"
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#ifdef UNIV_NONINL
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#include "row0vers.ic"
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#endif
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#include "dict0dict.h"
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#include "dict0boot.h"
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#include "btr0btr.h"
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#include "mach0data.h"
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#include "trx0rseg.h"
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#include "trx0trx.h"
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#include "trx0roll.h"
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#include "trx0undo.h"
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#include "trx0purge.h"
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#include "trx0rec.h"
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#include "que0que.h"
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#include "row0row.h"
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#include "row0upd.h"
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#include "rem0cmp.h"
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#include "read0read.h"
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#include "lock0lock.h"
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/*********************************************************************
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Finds out if an active transaction has inserted or modified a secondary
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index record. NOTE: the kernel mutex is temporarily released in this
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function! */
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trx_t*
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row_vers_impl_x_locked_off_kernel(
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/*==============================*/
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/* out: NULL if committed, else the active
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transaction; NOTE that the kernel mutex is
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temporarily released! */
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rec_t* rec, /* in: record in a secondary index */
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dict_index_t* index, /* in: the secondary index */
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const ulint* offsets)/* in: rec_get_offsets(rec, index) */
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{
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dict_index_t* clust_index;
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rec_t* clust_rec;
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ulint* clust_offsets;
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rec_t* version;
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rec_t* prev_version;
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dulint trx_id;
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dulint prev_trx_id;
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mem_heap_t* heap;
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mem_heap_t* heap2;
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dtuple_t* row;
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dtuple_t* entry = NULL; /* assignment to eliminate compiler
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warning */
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trx_t* trx;
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ulint vers_del;
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ulint rec_del;
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ulint err;
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mtr_t mtr;
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ulint comp;
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#ifdef UNIV_SYNC_DEBUG
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ut_ad(mutex_own(&kernel_mutex));
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ut_ad(!rw_lock_own(&(purge_sys->latch), RW_LOCK_SHARED));
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#endif /* UNIV_SYNC_DEBUG */
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mutex_exit(&kernel_mutex);
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mtr_start(&mtr);
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/* Search for the clustered index record: this is a time-consuming
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operation: therefore we release the kernel mutex; also, the release
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is required by the latching order convention. The latch on the
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clustered index locks the top of the stack of versions. We also
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reserve purge_latch to lock the bottom of the version stack. */
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clust_rec = row_get_clust_rec(BTR_SEARCH_LEAF, rec, index,
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&clust_index, &mtr);
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if (!clust_rec) {
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/* In a rare case it is possible that no clust rec is found
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for a secondary index record: if in row0umod.c
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row_undo_mod_remove_clust_low() we have already removed the
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clust rec, while purge is still cleaning and removing
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secondary index records associated with earlier versions of
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the clustered index record. In that case there cannot be
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any implicit lock on the secondary index record, because
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an active transaction which has modified the secondary index
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record has also modified the clustered index record. And in
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a rollback we always undo the modifications to secondary index
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records before the clustered index record. */
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mutex_enter(&kernel_mutex);
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mtr_commit(&mtr);
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return(NULL);
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}
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heap = mem_heap_create(1024);
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clust_offsets = rec_get_offsets(clust_rec, clust_index, NULL,
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ULINT_UNDEFINED, &heap);
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trx_id = row_get_rec_trx_id(clust_rec, clust_index, clust_offsets);
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mtr_s_lock(&(purge_sys->latch), &mtr);
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mutex_enter(&kernel_mutex);
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trx = NULL;
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if (!trx_is_active(trx_id)) {
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/* The transaction that modified or inserted clust_rec is no
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longer active: no implicit lock on rec */
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goto exit_func;
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}
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if (!lock_check_trx_id_sanity(trx_id, clust_rec, clust_index,
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clust_offsets, TRUE)) {
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/* Corruption noticed: try to avoid a crash by returning */
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goto exit_func;
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}
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comp = page_rec_is_comp(rec);
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ut_ad(index->table == clust_index->table);
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ut_ad(!!comp == dict_table_is_comp(index->table));
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ut_ad(!comp == !page_rec_is_comp(clust_rec));
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/* We look up if some earlier version, which was modified by the trx_id
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transaction, of the clustered index record would require rec to be in
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a different state (delete marked or unmarked, or have different field
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values, or not existing). If there is such a version, then rec was
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modified by the trx_id transaction, and it has an implicit x-lock on
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rec. Note that if clust_rec itself would require rec to be in a
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different state, then the trx_id transaction has not yet had time to
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modify rec, and does not necessarily have an implicit x-lock on rec. */
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rec_del = rec_get_deleted_flag(rec, comp);
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trx = NULL;
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version = clust_rec;
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for (;;) {
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mutex_exit(&kernel_mutex);
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/* While we retrieve an earlier version of clust_rec, we
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release the kernel mutex, because it may take time to access
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the disk. After the release, we have to check if the trx_id
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transaction is still active. We keep the semaphore in mtr on
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the clust_rec page, so that no other transaction can update
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it and get an implicit x-lock on rec. */
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heap2 = heap;
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heap = mem_heap_create(1024);
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err = trx_undo_prev_version_build(clust_rec, &mtr, version,
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clust_index, clust_offsets, heap,
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&prev_version);
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mem_heap_free(heap2); /* free version and clust_offsets */
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if (prev_version) {
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clust_offsets = rec_get_offsets(prev_version,
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clust_index, NULL,
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ULINT_UNDEFINED, &heap);
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row = row_build(ROW_COPY_POINTERS, clust_index,
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prev_version, clust_offsets, heap);
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entry = row_build_index_entry(row, index, heap);
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}
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mutex_enter(&kernel_mutex);
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if (!trx_is_active(trx_id)) {
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/* Transaction no longer active: no implicit x-lock */
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break;
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}
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/* If the transaction is still active, the previous version
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of clust_rec must be accessible if not a fresh insert; we
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may assert the following: */
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ut_ad(err == DB_SUCCESS);
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if (prev_version == NULL) {
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/* It was a freshly inserted version: there is an
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implicit x-lock on rec */
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trx = trx_get_on_id(trx_id);
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break;
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}
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/* If we get here, we know that the trx_id transaction is
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still active and it has modified prev_version. Let us check
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if prev_version would require rec to be in a different
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state. */
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vers_del = rec_get_deleted_flag(prev_version, comp);
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/* We check if entry and rec are identified in the alphabetical
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ordering */
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if (0 == cmp_dtuple_rec(entry, rec, offsets)) {
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/* The delete marks of rec and prev_version should be
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equal for rec to be in the state required by
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prev_version */
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if (rec_del != vers_del) {
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trx = trx_get_on_id(trx_id);
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break;
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}
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/* It is possible that the row was updated so that the
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secondary index record remained the same in
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alphabetical ordering, but the field values changed
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still. For example, 'abc' -> 'ABC'. Check also that. */
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dtuple_set_types_binary(entry,
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dtuple_get_n_fields(entry));
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if (0 != cmp_dtuple_rec(entry, rec, offsets)) {
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trx = trx_get_on_id(trx_id);
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break;
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}
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} else if (!rec_del) {
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/* The delete mark should be set in rec for it to be
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in the state required by prev_version */
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trx = trx_get_on_id(trx_id);
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break;
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}
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prev_trx_id = row_get_rec_trx_id(prev_version, clust_index,
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clust_offsets);
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if (0 != ut_dulint_cmp(trx_id, prev_trx_id)) {
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/* The versions modified by the trx_id transaction end
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to prev_version: no implicit x-lock */
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break;
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}
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version = prev_version;
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}/* for (;;) */
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exit_func:
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mtr_commit(&mtr);
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mem_heap_free(heap);
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return(trx);
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}
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/*********************************************************************
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Finds out if we must preserve a delete marked earlier version of a clustered
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index record, because it is >= the purge view. */
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ibool
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row_vers_must_preserve_del_marked(
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/*==============================*/
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/* out: TRUE if earlier version should be preserved */
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dulint trx_id, /* in: transaction id in the version */
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mtr_t* mtr) /* in: mtr holding the latch on the clustered index
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record; it will also hold the latch on purge_view */
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{
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#ifdef UNIV_SYNC_DEBUG
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ut_ad(!rw_lock_own(&(purge_sys->latch), RW_LOCK_SHARED));
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#endif /* UNIV_SYNC_DEBUG */
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mtr_s_lock(&(purge_sys->latch), mtr);
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if (trx_purge_update_undo_must_exist(trx_id)) {
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/* A purge operation is not yet allowed to remove this
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delete marked record */
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return(TRUE);
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}
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return(FALSE);
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}
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/*********************************************************************
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Finds out if a version of the record, where the version >= the current
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purge view, should have ientry as its secondary index entry. We check
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if there is any not delete marked version of the record where the trx
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id >= purge view, and the secondary index entry and ientry are identified in
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the alphabetical ordering; exactly in this case we return TRUE. */
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ibool
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row_vers_old_has_index_entry(
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/*=========================*/
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/* out: TRUE if earlier version should have */
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ibool also_curr,/* in: TRUE if also rec is included in the
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versions to search; otherwise only versions
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prior to it are searched */
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rec_t* rec, /* in: record in the clustered index; the
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caller must have a latch on the page */
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mtr_t* mtr, /* in: mtr holding the latch on rec; it will
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also hold the latch on purge_view */
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dict_index_t* index, /* in: the secondary index */
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dtuple_t* ientry) /* in: the secondary index entry */
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{
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rec_t* version;
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rec_t* prev_version;
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dict_index_t* clust_index;
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ulint* clust_offsets;
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mem_heap_t* heap;
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mem_heap_t* heap2;
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dtuple_t* row;
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dtuple_t* entry;
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ulint err;
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ulint comp;
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ut_ad(mtr_memo_contains(mtr, buf_block_align(rec), MTR_MEMO_PAGE_X_FIX)
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|| mtr_memo_contains(mtr, buf_block_align(rec),
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MTR_MEMO_PAGE_S_FIX));
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#ifdef UNIV_SYNC_DEBUG
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ut_ad(!rw_lock_own(&(purge_sys->latch), RW_LOCK_SHARED));
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#endif /* UNIV_SYNC_DEBUG */
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mtr_s_lock(&(purge_sys->latch), mtr);
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clust_index = dict_table_get_first_index(index->table);
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comp = page_rec_is_comp(rec);
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ut_ad(!dict_table_is_comp(index->table) == !comp);
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heap = mem_heap_create(1024);
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clust_offsets = rec_get_offsets(rec, clust_index, NULL,
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ULINT_UNDEFINED, &heap);
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if (also_curr && !rec_get_deleted_flag(rec, comp)) {
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row = row_build(ROW_COPY_POINTERS, clust_index,
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rec, clust_offsets, heap);
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entry = row_build_index_entry(row, index, heap);
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/* NOTE that we cannot do the comparison as binary
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fields because the row is maybe being modified so that
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the clustered index record has already been updated
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to a different binary value in a char field, but the
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collation identifies the old and new value anyway! */
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if (dtuple_datas_are_ordering_equal(ientry, entry)) {
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mem_heap_free(heap);
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return(TRUE);
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}
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}
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version = rec;
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for (;;) {
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heap2 = heap;
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heap = mem_heap_create(1024);
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err = trx_undo_prev_version_build(rec, mtr, version,
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clust_index, clust_offsets, heap,
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&prev_version);
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mem_heap_free(heap2); /* free version and clust_offsets */
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if (err != DB_SUCCESS || !prev_version) {
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/* Versions end here */
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mem_heap_free(heap);
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return(FALSE);
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}
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clust_offsets = rec_get_offsets(prev_version, clust_index,
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NULL, ULINT_UNDEFINED, &heap);
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if (!rec_get_deleted_flag(prev_version, comp)) {
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row = row_build(ROW_COPY_POINTERS, clust_index,
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prev_version, clust_offsets, heap);
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entry = row_build_index_entry(row, index, heap);
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/* NOTE that we cannot do the comparison as binary
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fields because maybe the secondary index record has
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already been updated to a different binary value in
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a char field, but the collation identifies the old
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and new value anyway! */
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if (dtuple_datas_are_ordering_equal(ientry, entry)) {
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mem_heap_free(heap);
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return(TRUE);
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}
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}
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version = prev_version;
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}
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}
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/*********************************************************************
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Constructs the version of a clustered index record which a consistent
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read should see. We assume that the trx id stored in rec is such that
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the consistent read should not see rec in its present version. */
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ulint
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row_vers_build_for_consistent_read(
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/*===============================*/
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/* out: DB_SUCCESS or DB_MISSING_HISTORY */
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rec_t* rec, /* in: record in a clustered index; the
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caller must have a latch on the page; this
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latch locks the top of the stack of versions
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of this records */
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mtr_t* mtr, /* in: mtr holding the latch on rec */
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dict_index_t* index, /* in: the clustered index */
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ulint** offsets,/* in/out: offsets returned by
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rec_get_offsets(rec, index) */
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read_view_t* view, /* in: the consistent read view */
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mem_heap_t** offset_heap,/* in/out: memory heap from which
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the offsets are allocated */
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mem_heap_t* in_heap,/* in: memory heap from which the memory for
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old_vers is allocated; memory for possible
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|
intermediate versions is allocated and freed
|
|
locally within the function */
|
|
rec_t** old_vers)/* out, own: old version, or NULL if the
|
|
record does not exist in the view, that is,
|
|
it was freshly inserted afterwards */
|
|
{
|
|
rec_t* version;
|
|
rec_t* prev_version;
|
|
dulint trx_id;
|
|
mem_heap_t* heap = NULL;
|
|
byte* buf;
|
|
ulint err;
|
|
|
|
ut_ad(index->type & DICT_CLUSTERED);
|
|
ut_ad(mtr_memo_contains(mtr, buf_block_align(rec), MTR_MEMO_PAGE_X_FIX)
|
|
|| mtr_memo_contains(mtr, buf_block_align(rec),
|
|
MTR_MEMO_PAGE_S_FIX));
|
|
#ifdef UNIV_SYNC_DEBUG
|
|
ut_ad(!rw_lock_own(&(purge_sys->latch), RW_LOCK_SHARED));
|
|
#endif /* UNIV_SYNC_DEBUG */
|
|
|
|
ut_ad(rec_offs_validate(rec, index, *offsets));
|
|
|
|
trx_id = row_get_rec_trx_id(rec, index, *offsets);
|
|
|
|
ut_ad(!read_view_sees_trx_id(view, trx_id));
|
|
|
|
rw_lock_s_lock(&(purge_sys->latch));
|
|
version = rec;
|
|
|
|
for (;;) {
|
|
mem_heap_t* heap2 = heap;
|
|
trx_undo_rec_t* undo_rec;
|
|
dulint roll_ptr;
|
|
dulint undo_no;
|
|
heap = mem_heap_create(1024);
|
|
|
|
/* If we have high-granularity consistent read view and
|
|
creating transaction of the view is the same as trx_id in
|
|
the record we see this record only in the case when
|
|
undo_no of the record is < undo_no in the view. */
|
|
|
|
if (view->type == VIEW_HIGH_GRANULARITY
|
|
&& ut_dulint_cmp(view->creator_trx_id, trx_id) == 0) {
|
|
|
|
roll_ptr = row_get_rec_roll_ptr(version, index,
|
|
*offsets);
|
|
undo_rec = trx_undo_get_undo_rec_low(roll_ptr, heap);
|
|
undo_no = trx_undo_rec_get_undo_no(undo_rec);
|
|
mem_heap_empty(heap);
|
|
|
|
if (ut_dulint_cmp(view->undo_no, undo_no) > 0) {
|
|
/* The view already sees this version: we can
|
|
copy it to in_heap and return */
|
|
|
|
buf = mem_heap_alloc(in_heap,
|
|
rec_offs_size(*offsets));
|
|
*old_vers = rec_copy(buf, version, *offsets);
|
|
rec_offs_make_valid(*old_vers, index, *offsets);
|
|
err = DB_SUCCESS;
|
|
|
|
break;
|
|
}
|
|
}
|
|
|
|
err = trx_undo_prev_version_build(rec, mtr, version, index,
|
|
*offsets, heap, &prev_version);
|
|
if (heap2) {
|
|
mem_heap_free(heap2); /* free version */
|
|
}
|
|
|
|
if (err != DB_SUCCESS) {
|
|
break;
|
|
}
|
|
|
|
if (prev_version == NULL) {
|
|
/* It was a freshly inserted version */
|
|
*old_vers = NULL;
|
|
err = DB_SUCCESS;
|
|
|
|
break;
|
|
}
|
|
|
|
*offsets = rec_get_offsets(prev_version, index, *offsets,
|
|
ULINT_UNDEFINED, offset_heap);
|
|
|
|
trx_id = row_get_rec_trx_id(prev_version, index, *offsets);
|
|
|
|
if (read_view_sees_trx_id(view, trx_id)) {
|
|
|
|
/* The view already sees this version: we can copy
|
|
it to in_heap and return */
|
|
|
|
buf = mem_heap_alloc(in_heap, rec_offs_size(*offsets));
|
|
*old_vers = rec_copy(buf, prev_version, *offsets);
|
|
rec_offs_make_valid(*old_vers, index, *offsets);
|
|
err = DB_SUCCESS;
|
|
|
|
break;
|
|
}
|
|
|
|
version = prev_version;
|
|
}/* for (;;) */
|
|
|
|
mem_heap_free(heap);
|
|
rw_lock_s_unlock(&(purge_sys->latch));
|
|
|
|
return(err);
|
|
}
|
|
|
|
/*********************************************************************
|
|
Constructs the last committed version of a clustered index record,
|
|
which should be seen by a semi-consistent read. */
|
|
|
|
ulint
|
|
row_vers_build_for_semi_consistent_read(
|
|
/*====================================*/
|
|
/* out: DB_SUCCESS or DB_MISSING_HISTORY */
|
|
rec_t* rec, /* in: record in a clustered index; the
|
|
caller must have a latch on the page; this
|
|
latch locks the top of the stack of versions
|
|
of this records */
|
|
mtr_t* mtr, /* in: mtr holding the latch on rec */
|
|
dict_index_t* index, /* in: the clustered index */
|
|
ulint** offsets,/* in/out: offsets returned by
|
|
rec_get_offsets(rec, index) */
|
|
mem_heap_t** offset_heap,/* in/out: memory heap from which
|
|
the offsets are allocated */
|
|
mem_heap_t* in_heap,/* in: memory heap from which the memory for
|
|
old_vers is allocated; memory for possible
|
|
intermediate versions is allocated and freed
|
|
locally within the function */
|
|
rec_t** old_vers)/* out, own: rec, old version, or NULL if the
|
|
record does not exist in the view, that is,
|
|
it was freshly inserted afterwards */
|
|
{
|
|
rec_t* version;
|
|
mem_heap_t* heap = NULL;
|
|
byte* buf;
|
|
ulint err;
|
|
dulint rec_trx_id;
|
|
|
|
ut_ad(index->type & DICT_CLUSTERED);
|
|
ut_ad(mtr_memo_contains(mtr, buf_block_align(rec), MTR_MEMO_PAGE_X_FIX)
|
|
|| mtr_memo_contains(mtr, buf_block_align(rec),
|
|
MTR_MEMO_PAGE_S_FIX));
|
|
#ifdef UNIV_SYNC_DEBUG
|
|
ut_ad(!rw_lock_own(&(purge_sys->latch), RW_LOCK_SHARED));
|
|
#endif /* UNIV_SYNC_DEBUG */
|
|
|
|
ut_ad(rec_offs_validate(rec, index, *offsets));
|
|
|
|
rw_lock_s_lock(&(purge_sys->latch));
|
|
/* The S-latch on purge_sys prevents the purge view from
|
|
changing. Thus, if we have an uncommitted transaction at
|
|
this point, then purge cannot remove its undo log even if
|
|
the transaction could commit now. */
|
|
|
|
version = rec;
|
|
|
|
for (;;) {
|
|
trx_t* version_trx;
|
|
mem_heap_t* heap2;
|
|
rec_t* prev_version;
|
|
dulint version_trx_id;
|
|
|
|
version_trx_id = row_get_rec_trx_id(
|
|
version, index, *offsets);
|
|
if (rec == version) {
|
|
rec_trx_id = version_trx_id;
|
|
}
|
|
|
|
mutex_enter(&kernel_mutex);
|
|
version_trx = trx_get_on_id(version_trx_id);
|
|
mutex_exit(&kernel_mutex);
|
|
|
|
if (!version_trx
|
|
|| version_trx->conc_state == TRX_NOT_STARTED
|
|
|| version_trx->conc_state == TRX_COMMITTED_IN_MEMORY) {
|
|
|
|
/* We found a version that belongs to a
|
|
committed transaction: return it. */
|
|
|
|
if (rec == version) {
|
|
*old_vers = rec;
|
|
err = DB_SUCCESS;
|
|
break;
|
|
}
|
|
|
|
/* We assume that a rolled-back transaction stays in
|
|
TRX_ACTIVE state until all the changes have been
|
|
rolled back and the transaction is removed from
|
|
the global list of transactions. */
|
|
|
|
if (!ut_dulint_cmp(rec_trx_id, version_trx_id)) {
|
|
/* The transaction was committed while
|
|
we searched for earlier versions.
|
|
Return the current version as a
|
|
semi-consistent read. */
|
|
|
|
version = rec;
|
|
*offsets = rec_get_offsets(version,
|
|
index, *offsets,
|
|
ULINT_UNDEFINED, offset_heap);
|
|
}
|
|
|
|
buf = mem_heap_alloc(in_heap, rec_offs_size(*offsets));
|
|
*old_vers = rec_copy(buf, version, *offsets);
|
|
rec_offs_make_valid(*old_vers, index, *offsets);
|
|
err = DB_SUCCESS;
|
|
|
|
break;
|
|
}
|
|
|
|
heap2 = heap;
|
|
heap = mem_heap_create(1024);
|
|
|
|
err = trx_undo_prev_version_build(rec, mtr, version, index,
|
|
*offsets, heap, &prev_version);
|
|
if (heap2) {
|
|
mem_heap_free(heap2); /* free version */
|
|
}
|
|
|
|
if (UNIV_UNLIKELY(err != DB_SUCCESS)) {
|
|
break;
|
|
}
|
|
|
|
if (prev_version == NULL) {
|
|
/* It was a freshly inserted version */
|
|
*old_vers = NULL;
|
|
err = DB_SUCCESS;
|
|
|
|
break;
|
|
}
|
|
|
|
version = prev_version;
|
|
*offsets = rec_get_offsets(version, index, *offsets,
|
|
ULINT_UNDEFINED, offset_heap);
|
|
}/* for (;;) */
|
|
|
|
if (heap) {
|
|
mem_heap_free(heap);
|
|
}
|
|
rw_lock_s_unlock(&(purge_sys->latch));
|
|
|
|
return(err);
|
|
}
|