diff options
Diffstat (limited to 'sql/sql_update.cc')
| -rw-r--r-- | sql/sql_update.cc | 41 |
1 files changed, 28 insertions, 13 deletions
diff --git a/sql/sql_update.cc b/sql/sql_update.cc index bb4540b48f3..0f470062981 100644 --- a/sql/sql_update.cc +++ b/sql/sql_update.cc @@ -1,4 +1,5 @@ /* Copyright (c) 2000, 2010, Oracle and/or its affiliates. All rights reserved. + Copyright (c) 2011 Monty Program Ab This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by @@ -437,23 +438,37 @@ int mysql_update(THD *thd, table->update_const_key_parts(conds); order= simple_remove_const(order, conds); - used_index= get_index_for_order(order, table, select, limit, - &need_sort, &reverse); - if (need_sort) - { // Assign table scan index to check below for modified key fields: - used_index= table->file->key_used_on_scan; + if (select && select->quick && select->quick->unique_key_range()) + { // Single row select (always "ordered"): Ok to use with key field UPDATE + need_sort= FALSE; + used_index= MAX_KEY; + used_key_is_modified= FALSE; } - if (used_index != MAX_KEY) - { // Check if we are modifying a key that we are used to search with: - used_key_is_modified= is_key_used(table, used_index, table->write_set); + else + { + used_index= get_index_for_order(order, table, select, limit, + &need_sort, &reverse); + if (select && select->quick) + { + DBUG_ASSERT(need_sort || used_index == select->quick->index); + used_key_is_modified= (!select->quick->unique_key_range() && + select->quick->is_keys_used(table->write_set)); + } + else + { + if (need_sort) + { // Assign table scan index to check below for modified key fields: + used_index= table->file->key_used_on_scan; + } + if (used_index != MAX_KEY) + { // Check if we are modifying a key that we are used to search with: + used_key_is_modified= is_key_used(table, used_index, table->write_set); + } + } } -#ifdef WITH_PARTITION_STORAGE_ENGINE if (used_key_is_modified || order || partition_key_modified(table, table->write_set)) -#else - if (used_key_is_modified || order) -#endif { /* We can't update table directly; We must first search after all @@ -2098,7 +2113,7 @@ int multi_update::do_updates() { if ((local_error= tbl->file->ha_rnd_pos(tbl->record[0], - (uchar*) tmp_table->field[field_num]->ptr))) + (uchar *) tmp_table->field[field_num]->ptr))) { err_table= tbl; goto err; |