From 0f7888f7cae3edac5e168aea44ba39b99aa29026 Mon Sep 17 00:00:00 2001 From: Evgeny Potemkin Date: Thu, 28 Jun 2012 16:53:45 +0400 Subject: Bug#14248833: UPDATE ON INNODB TABLE ENTERS RECURSION Introduction of cost based decision on filesort vs index for UPDATE statements changed detection of the fact that the index used to scan the table is being updated. The new design missed the case of index merge when there is no single index to check. That was worked until a recent change in InnoDB after which it went into infinite recursion if update of the used index wasn't properly detected. The fix consists of 'used key being updated' detection code from 5.1. --- sql/sql_update.cc | 9 +++++++++ 1 file changed, 9 insertions(+) (limited to 'sql/sql_update.cc') diff --git a/sql/sql_update.cc b/sql/sql_update.cc index 754170e4c55..c4a95edcfc2 100644 --- a/sql/sql_update.cc +++ b/sql/sql_update.cc @@ -450,6 +450,15 @@ int mysql_update(THD *thd, { // 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 if (select && select->quick) + { + /* + select->quick != NULL and used_index == MAX_KEY happens for index + merge and should be handled in a different way. + */ + used_key_is_modified= (!select->quick->unique_key_range() && + select->quick->is_keys_used(table->write_set)); + } #ifdef WITH_PARTITION_STORAGE_ENGINE if (used_key_is_modified || order || -- cgit v1.2.1