diff options
Diffstat (limited to 'storage/innodb_plugin/row/row0sel.c')
-rw-r--r-- | storage/innodb_plugin/row/row0sel.c | 103 |
1 files changed, 83 insertions, 20 deletions
diff --git a/storage/innodb_plugin/row/row0sel.c b/storage/innodb_plugin/row/row0sel.c index 2861235a995..76c144e5a8c 100644 --- a/storage/innodb_plugin/row/row0sel.c +++ b/storage/innodb_plugin/row/row0sel.c @@ -416,7 +416,7 @@ row_sel_fetch_columns( field_no))) { /* Copy an externally stored field to the - temporary heap */ + temporary heap, if possible. */ heap = mem_heap_create(1); @@ -425,6 +425,17 @@ row_sel_fetch_columns( dict_table_zip_size(index->table), field_no, &len, heap); + /* data == NULL means that the + externally stored field was not + written yet. This record + should only be seen by + recv_recovery_rollback_active() or any + TRX_ISO_READ_UNCOMMITTED + transactions. The InnoDB SQL parser + (the sole caller of this function) + does not implement READ UNCOMMITTED, + and it is not involved during rollback. */ + ut_a(data); ut_a(len != UNIV_SQL_NULL); needs_copy = TRUE; @@ -926,6 +937,7 @@ row_sel_get_clust_rec( when plan->clust_pcur was positioned. The latch will not be released until mtr_commit(mtr). */ + ut_ad(!rec_get_deleted_flag(clust_rec, rec_offs_comp(offsets))); row_sel_fetch_columns(index, clust_rec, offsets, UT_LIST_GET_FIRST(plan->columns)); *out_rec = clust_rec; @@ -1628,6 +1640,13 @@ skip_lock: } if (old_vers == NULL) { + /* The record does not exist + in our read view. Skip it, but + first attempt to determine + whether the index segment we + are searching through has been + exhausted. */ + offsets = rec_get_offsets( rec, index, offsets, ULINT_UNDEFINED, &heap); @@ -2647,9 +2666,8 @@ Convert a row in the Innobase format to a row in the MySQL format. Note that the template in prebuilt may advise us to copy only a few columns to mysql_rec, other columns are left blank. All columns may not be needed in the query. -@return TRUE if success, FALSE if could not allocate memory for a BLOB -(though we may also assert in that case) */ -static +@return TRUE on success, FALSE if not all columns could be retrieved */ +static __attribute__((warn_unused_result)) ibool row_sel_store_mysql_rec( /*====================*/ @@ -2672,6 +2690,7 @@ row_sel_store_mysql_rec( ut_ad(prebuilt->mysql_template); ut_ad(prebuilt->default_rec); ut_ad(rec_offs_validate(rec, NULL, offsets)); + ut_ad(!rec_get_deleted_flag(rec, rec_offs_comp(offsets))); if (UNIV_LIKELY_NULL(prebuilt->blob_heap)) { mem_heap_free(prebuilt->blob_heap); @@ -2719,6 +2738,21 @@ row_sel_store_mysql_rec( dict_table_zip_size(prebuilt->table), templ->rec_field_no, &len, heap); + if (UNIV_UNLIKELY(!data)) { + /* The externally stored field + was not written yet. This + record should only be seen by + recv_recovery_rollback_active() + or any TRX_ISO_READ_UNCOMMITTED + transactions. */ + + if (extern_field_heap) { + mem_heap_free(extern_field_heap); + } + + return(FALSE); + } + ut_a(len != UNIV_SQL_NULL); } else { /* Field is stored in the row. */ @@ -3136,9 +3170,10 @@ row_sel_pop_cached_row_for_mysql( } /********************************************************************//** -Pushes a row for MySQL to the fetch cache. */ -UNIV_INLINE -void +Pushes a row for MySQL to the fetch cache. +@return TRUE on success, FALSE if the record contains incomplete BLOBs */ +UNIV_INLINE __attribute__((warn_unused_result)) +ibool row_sel_push_cache_row_for_mysql( /*=============================*/ row_prebuilt_t* prebuilt, /*!< in: prebuilt struct */ @@ -3180,10 +3215,11 @@ row_sel_push_cache_row_for_mysql( prebuilt->fetch_cache[ prebuilt->n_fetch_cached], prebuilt, rec, offsets))) { - ut_error; + return(FALSE); } prebuilt->n_fetch_cached++; + return(TRUE); } /*********************************************************************//** @@ -3578,11 +3614,21 @@ row_search_for_mysql( if (!row_sel_store_mysql_rec(buf, prebuilt, rec, offsets)) { - err = DB_TOO_BIG_RECORD; - - /* We let the main loop to do the - error handling */ - goto shortcut_fails_too_big_rec; + /* Only fresh inserts may contain + incomplete externally stored + columns. Pretend that such + records do not exist. Such + records may only be accessed + at the READ UNCOMMITTED + isolation level or when + rolling back a recovered + transaction. Rollback happens + at a lower level, not here. */ + ut_a(trx->isolation_level + == TRX_ISO_READ_UNCOMMITTED); + + /* Proceed as in case SEL_RETRY. */ + break; } mtr_commit(&mtr); @@ -3622,7 +3668,7 @@ release_search_latch_if_needed: default: ut_ad(0); } -shortcut_fails_too_big_rec: + mtr_commit(&mtr); mtr_start(&mtr); } @@ -4357,9 +4403,18 @@ requires_clust_rec: not cache rows because there the cursor is a scrollable cursor. */ - row_sel_push_cache_row_for_mysql(prebuilt, result_rec, - offsets); - if (prebuilt->n_fetch_cached == MYSQL_FETCH_CACHE_SIZE) { + if (!row_sel_push_cache_row_for_mysql(prebuilt, result_rec, + offsets)) { + /* Only fresh inserts may contain incomplete + externally stored columns. Pretend that such + records do not exist. Such records may only be + accessed at the READ UNCOMMITTED isolation + level or when rolling back a recovered + transaction. Rollback happens at a lower + level, not here. */ + ut_a(trx->isolation_level == TRX_ISO_READ_UNCOMMITTED); + } else if (prebuilt->n_fetch_cached + == MYSQL_FETCH_CACHE_SIZE) { goto got_row; } @@ -4375,9 +4430,17 @@ requires_clust_rec: } else { if (!row_sel_store_mysql_rec(buf, prebuilt, result_rec, offsets)) { - err = DB_TOO_BIG_RECORD; - - goto lock_wait_or_error; + /* Only fresh inserts may contain + incomplete externally stored + columns. Pretend that such records do + not exist. Such records may only be + accessed at the READ UNCOMMITTED + isolation level or when rolling back a + recovered transaction. Rollback + happens at a lower level, not here. */ + ut_a(trx->isolation_level + == TRX_ISO_READ_UNCOMMITTED); + goto next_rec; } } |