Bug #56494 Segfault in upgrade_shared_lock_to_exclusive() for

           REPAIR of merge table
Bug #56422 CHECK TABLE run when the table is locked reports
           corruption along with timeout

The crash happened if a table maintenance statement (ANALYZE TABLE,
REPAIR TABLE, etc.) was executed on a MERGE table and opening and 
locking a child table failed. This could for example happen if a child
table did not exist or if a lock timeout happened while waiting for
a conflicting metadata lock to disappear.

Since opening and locking the MERGE table and its children failed,
the tables would be closed and the metadata locks released.
However, TABLE_LIST::table for the MERGE table would still be set,
with its value invalid since the tables had been closed.
This caused the table maintenance statement to try to continue
and upgrade the metadata lock on the MERGE table. But since the lock
already had been released, this caused a segfault.

This patch fixes the problem by setting TABLE_LIST::table to NULL 
if open_and_lock_tables() fails. This prevents maintenance
statements from continuing and trying to upgrade the metadata lock.

The patch includes a 5.5 version of the fix for
Bug #46339 crash on REPAIR TABLE merge table USE_FRM.
This bug caused REPAIR TABLE ... USE_FRM to give an assert 
when used on merge tables.

The patch also enables the CHECK TABLE statement for log tables.
Before, CHECK TABLE for log tables gave ER_CANT_LOCK_LOG_TABLE,
yet still counted the statement as successfully executed.
With the changes to table maintenance statement error handling
in this patch, CHECK TABLE would no longer be considered as
successful in this case. This would have caused upgrade scripts
to mistakenly think that the general and slow logs are corrupted
and have to be repaired. Enabling CHECK TABLES for log tables
prevents this from happening.

Finally, the patch changes the error message from "Corrupt" to
"Operation failed" for a number of issues not related to table
corruption. For example "Lock wait timeout exceeded" and 
"Deadlock found trying to get lock".

Test cases added to merge.test and check.test.

mysql-test/r/check.result

@@ -23,3 +23,19 @@ REPAIR TABLE t1;
 Table	Op	Msg_type	Msg_text
 test.t1	repair	status	OK
 DROP TABLE t1;
+#
+# Bug#56422 CHECK TABLE run when the table is locked reports corruption
+#           along with timeout
+#
+DROP TABLE IF EXISTS t1;
+CREATE TABLE t1(a INT);
+LOCK TABLE t1 WRITE;
+# Connection con1
+SET lock_wait_timeout= 1;
+CHECK TABLE t1;
+Table	Op	Msg_type	Msg_text
+test.t1	check	Error	Lock wait timeout exceeded; try restarting transaction
+test.t1	check	status	Operation failed
+# Connection default
+UNLOCK TABLES;
+DROP TABLE t1;

mysql-test/r/log_tables_upgrade.result

@@ -17,9 +17,7 @@ mysql.columns_priv                                 OK
 mysql.db                                           OK
 mysql.event                                        OK
 mysql.func                                         OK
-mysql.general_log
-Error    : You can't use locks with log tables.
-status   : OK
+mysql.general_log                                  OK
 mysql.help_category                                OK
 mysql.help_keyword                                 OK
 mysql.help_relation                                OK
@@ -31,9 +29,7 @@ mysql.proc                                         OK
 mysql.procs_priv                                   OK
 mysql.renamed_general_log                          OK
 mysql.servers                                      OK
-mysql.slow_log
-Error    : You can't use locks with log tables.
-status   : OK
+mysql.slow_log                                     OK
 mysql.tables_priv                                  OK
 mysql.time_zone                                    OK
 mysql.time_zone_leap_second                        OK

mysql-test/r/merge.result

@@ -2358,6 +2358,48 @@ t2 WHERE b SOUNDS LIKE e AND d = 1;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	NULL	NULL	NULL	NULL	NULL	NULL	NULL	Impossible WHERE noticed after reading const tables
 DROP TABLE t2, t1;
+#
+# Bug#46339 - crash on REPAIR TABLE merge table USE_FRM
+#
+DROP TABLE IF EXISTS m1, t1;
+CREATE TABLE t1 (c1 INT) ENGINE=MYISAM;
+CREATE TABLE m1 (c1 INT) ENGINE=MRG_MyISAM UNION=(t1) INSERT_METHOD=LAST;
+LOCK TABLE m1 READ;
+REPAIR TABLE m1 USE_FRM;
+Table	Op	Msg_type	Msg_text
+test.m1	repair	Error	Table 'm1' was locked with a READ lock and can't be updated
+test.m1	repair	status	Operation failed
+UNLOCK TABLES;
+REPAIR TABLE m1 USE_FRM;
+Table	Op	Msg_type	Msg_text
+test.m1	repair	note	The storage engine for the table doesn't support repair
+DROP TABLE m1,t1;
+CREATE TABLE m1 (f1 BIGINT) ENGINE=MRG_MyISAM UNION(t1);
+REPAIR TABLE m1 USE_FRM;
+Table	Op	Msg_type	Msg_text
+test.m1	repair	Warning	Can't open table
+test.m1	repair	error	Corrupt
+CREATE TABLE t1 (f1 BIGINT) ENGINE = MyISAM;
+REPAIR TABLE m1 USE_FRM;
+Table	Op	Msg_type	Msg_text
+test.m1	repair	note	The storage engine for the table doesn't support repair
+REPAIR TABLE m1;
+Table	Op	Msg_type	Msg_text
+test.m1	repair	note	The storage engine for the table doesn't support repair
+DROP TABLE m1, t1;
+CREATE TEMPORARY TABLE m1 (f1 BIGINT) ENGINE=MRG_MyISAM UNION(t1);
+REPAIR TABLE m1 USE_FRM;
+Table	Op	Msg_type	Msg_text
+test.m1	repair	Error	Table 'test.m1' doesn't exist
+test.m1	repair	error	Corrupt
+CREATE TEMPORARY TABLE t1 (f1 BIGINT) ENGINE=MyISAM;
+REPAIR TABLE m1 USE_FRM;
+Table	Op	Msg_type	Msg_text
+m1	repair	error	Cannot repair temporary table from .frm file
+REPAIR TABLE m1;
+Table	Op	Msg_type	Msg_text
+test.m1	repair	note	The storage engine for the table doesn't support repair
+DROP TABLE m1, t1;
 End of 5.1 tests
 #
 # An additional test case for Bug#27430 Crash in subquery code
@@ -2677,7 +2719,7 @@ OPTIMIZE TABLE t1;
 Table	Op	Msg_type	Msg_text
 test.t1	optimize	Error	Table 'test.t_not_exists' doesn't exist
 test.t1	optimize	Error	Unable to open underlying table which is differently defined or of non-MyISAM type or doesn't exist
-test.t1	optimize	note	The storage engine for the table doesn't support optimize
+test.t1	optimize	error	Corrupt
 DROP TABLE t1;
 #
 # Bug#36171 - CREATE TEMPORARY TABLE and MERGE engine
@@ -3575,4 +3617,48 @@ ERROR HY000: The definition of table 'v1' prevents operation DELETE on table 'm1
 drop view v1;
 drop temporary table tmp;
 drop table t1, t2, t3, m1, m2;
+#
+# Bug#56494 Segfault in upgrade_shared_lock_to_exclusive() for
+#           REPAIR of merge table
+#
+DROP TABLE IF EXISTS t1, t2, t_not_exists;
+CREATE TABLE t1(a INT);
+ALTER TABLE t1 engine= MERGE UNION (t_not_exists);
+ANALYZE TABLE t1;
+Table	Op	Msg_type	Msg_text
+test.t1	analyze	Error	Table 'test.t_not_exists' doesn't exist
+test.t1	analyze	Error	Unable to open underlying table which is differently defined or of non-MyISAM type or doesn't exist
+test.t1	analyze	error	Corrupt
+CHECK TABLE t1;
+Table	Op	Msg_type	Msg_text
+test.t1	check	Error	Table 'test.t_not_exists' doesn't exist
+test.t1	check	Error	Unable to open underlying table which is differently defined or of non-MyISAM type or doesn't exist
+test.t1	check	error	Corrupt
+CHECKSUM TABLE t1;
+Table	Checksum
+test.t1	NULL
+Warnings:
+Error	1146	Table 'test.t_not_exists' doesn't exist
+Error	1168	Unable to open underlying table which is differently defined or of non-MyISAM type or doesn't exist
+OPTIMIZE TABLE t1;
+Table	Op	Msg_type	Msg_text
+test.t1	optimize	Error	Table 'test.t_not_exists' doesn't exist
+test.t1	optimize	Error	Unable to open underlying table which is differently defined or of non-MyISAM type or doesn't exist
+test.t1	optimize	error	Corrupt
+REPAIR TABLE t1;
+Table	Op	Msg_type	Msg_text
+test.t1	repair	Error	Table 'test.t_not_exists' doesn't exist
+test.t1	repair	Error	Unable to open underlying table which is differently defined or of non-MyISAM type or doesn't exist
+test.t1	repair	error	Corrupt
+REPAIR TABLE t1 USE_FRM;
+Table	Op	Msg_type	Msg_text
+test.t1	repair	Warning	Can't open table
+test.t1	repair	error	Corrupt
+DROP TABLE t1;
+CREATE TABLE t1(a INT);
+CREATE TABLE t2(a INT) engine= MERGE UNION (t1);
+REPAIR TABLE t2 USE_FRM;
+Table	Op	Msg_type	Msg_text
+test.t2	repair	note	The storage engine for the table doesn't support repair
+DROP TABLE t1, t2;
 End of 6.0 tests

mysql-test/r/myisampack.result

@@ -46,14 +46,12 @@ insert into t1 select * from t1;
 flush tables;
 optimize table t1;
 Table	Op	Msg_type	Msg_text
-test.t1	optimize	error	Table 'test.t1' is read only
-Warnings:
-Error	1036	Table 't1' is read only
+test.t1	optimize	Error	Table 't1' is read only
+test.t1	optimize	status	Operation failed
 repair table t1;
 Table	Op	Msg_type	Msg_text
-test.t1	repair	error	Table 'test.t1' is read only
-Warnings:
-Error	1036	Table 't1' is read only
+test.t1	repair	Error	Table 't1' is read only
+test.t1	repair	status	Operation failed
 drop table t1;
 #
 # BUG#41541 - Valgrind warnings on packed MyISAM table

mysql-test/r/mysql_upgrade.result

@@ -5,9 +5,7 @@ mysql.columns_priv                                 OK
 mysql.db                                           OK
 mysql.event                                        OK
 mysql.func                                         OK
-mysql.general_log
-Error    : You can't use locks with log tables.
-status   : OK
+mysql.general_log                                  OK
 mysql.help_category                                OK
 mysql.help_keyword                                 OK
 mysql.help_relation                                OK
@@ -18,9 +16,7 @@ mysql.plugin                                       OK
 mysql.proc                                         OK
 mysql.procs_priv                                   OK
 mysql.servers                                      OK
-mysql.slow_log
-Error    : You can't use locks with log tables.
-status   : OK
+mysql.slow_log                                     OK
 mysql.tables_priv                                  OK
 mysql.time_zone                                    OK
 mysql.time_zone_leap_second                        OK
@@ -37,9 +33,7 @@ mysql.columns_priv                                 OK
 mysql.db                                           OK
 mysql.event                                        OK
 mysql.func                                         OK
-mysql.general_log
-Error    : You can't use locks with log tables.
-status   : OK
+mysql.general_log                                  OK
 mysql.help_category                                OK
 mysql.help_keyword                                 OK
 mysql.help_relation                                OK
@@ -50,9 +44,7 @@ mysql.plugin                                       OK
 mysql.proc                                         OK
 mysql.procs_priv                                   OK
 mysql.servers                                      OK
-mysql.slow_log
-Error    : You can't use locks with log tables.
-status   : OK
+mysql.slow_log                                     OK
 mysql.tables_priv                                  OK
 mysql.time_zone                                    OK
 mysql.time_zone_leap_second                        OK
@@ -69,9 +61,7 @@ mysql.columns_priv                                 OK
 mysql.db                                           OK
 mysql.event                                        OK
 mysql.func                                         OK
-mysql.general_log
-Error    : You can't use locks with log tables.
-status   : OK
+mysql.general_log                                  OK
 mysql.help_category                                OK
 mysql.help_keyword                                 OK
 mysql.help_relation                                OK
@@ -82,9 +72,7 @@ mysql.plugin                                       OK
 mysql.proc                                         OK
 mysql.procs_priv                                   OK
 mysql.servers                                      OK
-mysql.slow_log
-Error    : You can't use locks with log tables.
-status   : OK
+mysql.slow_log                                     OK
 mysql.tables_priv                                  OK
 mysql.time_zone                                    OK
 mysql.time_zone_leap_second                        OK
@@ -103,9 +91,7 @@ mysql.columns_priv                                 OK
 mysql.db                                           OK
 mysql.event                                        OK
 mysql.func                                         OK
-mysql.general_log
-Error    : You can't use locks with log tables.
-status   : OK
+mysql.general_log                                  OK
 mysql.help_category                                OK
 mysql.help_keyword                                 OK
 mysql.help_relation                                OK
@@ -116,9 +102,7 @@ mysql.plugin                                       OK
 mysql.proc                                         OK
 mysql.procs_priv                                   OK
 mysql.servers                                      OK
-mysql.slow_log
-Error    : You can't use locks with log tables.
-status   : OK
+mysql.slow_log                                     OK
 mysql.tables_priv                                  OK
 mysql.time_zone                                    OK
 mysql.time_zone_leap_second                        OK
@@ -141,9 +125,7 @@ mysql.columns_priv                                 OK
 mysql.db                                           OK
 mysql.event                                        OK
 mysql.func                                         OK
-mysql.general_log
-Error    : You can't use locks with log tables.
-status   : OK
+mysql.general_log                                  OK
 mysql.help_category                                OK
 mysql.help_keyword                                 OK
 mysql.help_relation                                OK
@@ -154,9 +136,7 @@ mysql.plugin                                       OK
 mysql.proc                                         OK
 mysql.procs_priv                                   OK
 mysql.servers                                      OK
-mysql.slow_log
-Error    : You can't use locks with log tables.
-status   : OK
+mysql.slow_log                                     OK
 mysql.tables_priv                                  OK
 mysql.time_zone                                    OK
 mysql.time_zone_leap_second                        OK
@@ -182,9 +162,7 @@ mysql.columns_priv                                 OK
 mysql.db                                           OK
 mysql.event                                        OK
 mysql.func                                         OK
-mysql.general_log
-Error    : You can't use locks with log tables.
-status   : OK
+mysql.general_log                                  OK
 mysql.help_category                                OK
 mysql.help_keyword                                 OK
 mysql.help_relation                                OK
@@ -195,9 +173,7 @@ mysql.plugin                                       OK
 mysql.proc                                         OK
 mysql.procs_priv                                   OK
 mysql.servers                                      OK
-mysql.slow_log
-Error    : You can't use locks with log tables.
-status   : OK
+mysql.slow_log                                     OK
 mysql.tables_priv                                  OK
 mysql.time_zone                                    OK
 mysql.time_zone_leap_second                        OK

mysql-test/r/mysql_upgrade_ssl.result

@@ -7,9 +7,7 @@ mysql.columns_priv                                 OK
 mysql.db                                           OK
 mysql.event                                        OK
 mysql.func                                         OK
-mysql.general_log
-Error    : You can't use locks with log tables.
-status   : OK
+mysql.general_log                                  OK
 mysql.help_category                                OK
 mysql.help_keyword                                 OK
 mysql.help_relation                                OK
@@ -20,9 +18,7 @@ mysql.plugin                                       OK
 mysql.proc                                         OK
 mysql.procs_priv                                   OK
 mysql.servers                                      OK
-mysql.slow_log
-Error    : You can't use locks with log tables.
-status   : OK
+mysql.slow_log                                     OK
 mysql.tables_priv                                  OK
 mysql.time_zone                                    OK
 mysql.time_zone_leap_second                        OK

mysql-test/t/check.test

@@ -53,5 +53,29 @@ REPAIR TABLE t1;
 DROP TABLE t1;
 
 
+--echo #
+--echo # Bug#56422 CHECK TABLE run when the table is locked reports corruption
+--echo #           along with timeout
+--echo #
+
+--disable_warnings
+DROP TABLE IF EXISTS t1;
+--enable_warnings
+
+CREATE TABLE t1(a INT);
+LOCK TABLE t1 WRITE;
+
+--echo # Connection con1
+connect(con1, localhost, root);
+SET lock_wait_timeout= 1;
+CHECK TABLE t1;
+
+--echo # Connection default
+connection default;
+UNLOCK TABLES;
+DROP TABLE t1;
+disconnect con1;
+
+
 # Wait till we reached the initial number of concurrent sessions
 --source include/wait_until_count_sessions.inc

mysql-test/t/merge.test

@@ -1734,6 +1734,84 @@ t2 WHERE b SOUNDS LIKE e AND d = 1;
 
 DROP TABLE t2, t1;
 
+--echo #
+--echo # Bug#46339 - crash on REPAIR TABLE merge table USE_FRM
+--echo #
+--disable_warnings
+DROP TABLE IF EXISTS m1, t1;
+--enable_warnings
+#
+# Test derived from a proposal of Shane Bester.
+#
+CREATE TABLE t1 (c1 INT) ENGINE=MYISAM;
+CREATE TABLE m1 (c1 INT) ENGINE=MRG_MyISAM UNION=(t1) INSERT_METHOD=LAST;
+#
+# REPAIR ... USE_FRM with LOCK TABLES.
+#
+LOCK TABLE m1 READ;
+REPAIR TABLE m1 USE_FRM;
+UNLOCK TABLES;
+#
+# REPAIR ... USE_FRM without LOCK TABLES.
+#
+# This statement crashed the server (Bug#46339).
+#
+REPAIR TABLE m1 USE_FRM;
+#
+DROP TABLE m1,t1;
+#
+# Test derived from a proposal of Matthias Leich.
+#
+# Base table is missing.
+#
+CREATE TABLE m1 (f1 BIGINT) ENGINE=MRG_MyISAM UNION(t1);
+#
+# This statement crashed the server (Bug#46339).
+#
+REPAIR TABLE m1 USE_FRM;
+#
+# Create base table.
+#
+CREATE TABLE t1 (f1 BIGINT) ENGINE = MyISAM;
+#
+# This statement crashed the server (Bug#46339).
+#
+REPAIR TABLE m1 USE_FRM;
+#
+# Normal repair as reference.
+#
+REPAIR TABLE m1;
+#
+# Cleanup.
+#
+DROP TABLE m1, t1;
+#
+# Same with temporary tables.
+#
+# Base table is missing.
+#
+CREATE TEMPORARY TABLE m1 (f1 BIGINT) ENGINE=MRG_MyISAM UNION(t1);
+#
+# This statement crashed the server (Bug#46339).
+#
+REPAIR TABLE m1 USE_FRM;
+#
+# Create base table.
+#
+CREATE TEMPORARY TABLE t1 (f1 BIGINT) ENGINE=MyISAM;
+#
+# This statement crashed the server (Bug#46339).
+#
+REPAIR TABLE m1 USE_FRM;
+#
+# Normal repair as reference.
+#
+REPAIR TABLE m1;
+#
+# Cleanup.
+#
+DROP TABLE m1, t1;
+
 --echo End of 5.1 tests
 
 --echo #
@@ -2668,6 +2746,36 @@ drop temporary table tmp;
 drop table t1, t2, t3, m1, m2;
 
 
+--echo #
+--echo # Bug#56494 Segfault in upgrade_shared_lock_to_exclusive() for
+--echo #           REPAIR of merge table
+--echo #
+
+--disable_warnings
+DROP TABLE IF EXISTS t1, t2, t_not_exists;
+--enable_warnings
+
+CREATE TABLE t1(a INT);
+ALTER TABLE t1 engine= MERGE UNION (t_not_exists);
+# This caused the segfault
+ANALYZE TABLE t1;
+CHECK TABLE t1;
+CHECKSUM TABLE t1;
+OPTIMIZE TABLE t1;
+REPAIR TABLE t1;
+
+# This caused an assert
+REPAIR TABLE t1 USE_FRM;
+
+DROP TABLE t1;
+CREATE TABLE t1(a INT);
+CREATE TABLE t2(a INT) engine= MERGE UNION (t1);
+# This caused an assert
+REPAIR TABLE t2 USE_FRM;
+
+DROP TABLE t1, t2;
+
+
 --echo End of 6.0 tests
 
 --disable_result_log

sql/sql_admin.cc

@@ -111,9 +111,6 @@ static int prepare_for_repair(THD *thd, TABLE_LIST *table_list,
     table= &tmp_table;
   }
 
-  /* A MERGE table must not come here. */
-  DBUG_ASSERT(table->file->ht->db_type != DB_TYPE_MRG_MYISAM);
-
   /*
     REPAIR TABLE ... USE_FRM for temporary tables makes little sense.
   */
@@ -151,6 +148,9 @@ static int prepare_for_repair(THD *thd, TABLE_LIST *table_list,
   if (!ext[0] || !ext[1])
     goto end;					// No data file
 
+  /* A MERGE table must not come here. */
+  DBUG_ASSERT(table->file->ht->db_type != DB_TYPE_MRG_MYISAM);
+
   // Name of data file
   strxmov(from, table->s->normalized_path.str, ext[1], NullS);
   if (!mysql_file_stat(key_file_misc, from, &stat_info, MYF(0)))
@@ -231,6 +231,26 @@ static int prepare_for_repair(THD *thd, TABLE_LIST *table_list,
 }
 
 
+/**
+  Check if a given error is something that could occur during
+  open_and_lock_tables() that does not indicate table corruption.
+
+  @param  sql_errno  Error number to check.
+
+  @retval TRUE       Error does not indicate table corruption.
+  @retval FALSE      Error could indicate table corruption.
+*/
+
+static inline bool table_not_corrupt_error(uint sql_errno)
+{
+  return (sql_errno == ER_NO_SUCH_TABLE ||
+          sql_errno == ER_FILE_NOT_FOUND ||
+          sql_errno == ER_LOCK_WAIT_TIMEOUT ||
+          sql_errno == ER_LOCK_DEADLOCK ||
+          sql_errno == ER_CANT_LOCK_LOG_TABLE ||
+          sql_errno == ER_OPEN_AS_READONLY);
+}
+
 
 /*
   RETURN VALUES
@@ -311,6 +331,12 @@ static bool mysql_admin_table(THD* thd, TABLE_LIST* tables,
       lex->query_tables= table;
       lex->query_tables_last= &table->next_global;
       lex->query_tables_own_last= 0;
+      /*
+        Under locked tables, we know that the table can be opened,
+        so any errors opening the table are logical errors.
+        In these cases it makes sense to report them.
+      */
+      if (!thd->locked_tables_mode)
         thd->no_warnings_for_error= no_warnings_for_error;
       if (view_operator_func == NULL)
         table->required_type=FRMTYPE_TABLE;
@@ -320,6 +346,14 @@ static bool mysql_admin_table(THD* thd, TABLE_LIST* tables,
       table->next_global= save_next_global;
       table->next_local= save_next_local;
       thd->open_options&= ~extra_open_options;
+
+      /*
+        If open_and_lock_tables() failed, close_thread_tables() will close
+        the table and table->table can therefore be invalid.
+      */
+      if (open_error)
+        table->table= NULL;
+
       /*
         Under locked tables, we know that the table can be opened,
         so any errors opening the table are logical errors.
@@ -418,9 +452,7 @@ static bool mysql_admin_table(THD* thd, TABLE_LIST* tables,
         push_warning(thd, MYSQL_ERROR::WARN_LEVEL_WARN,
                      ER_VIEW_CHECKSUM, ER(ER_VIEW_CHECKSUM));
       if (thd->stmt_da->is_error() &&
-          (thd->stmt_da->sql_errno() == ER_NO_SUCH_TABLE ||
-           thd->stmt_da->sql_errno() == ER_FILE_NOT_FOUND))
-        /* A missing table is just issued as a failed command */
+          table_not_corrupt_error(thd->stmt_da->sql_errno()))
         result_code= HA_ADMIN_FAILED;
       else
         /* Default failure code is corrupt table */

sql/sql_parse.cc

@@ -401,6 +401,7 @@ void init_update_queries(void)
   sql_command_flags[SQLCOM_REPAIR]=    CF_WRITE_LOGS_COMMAND | CF_AUTO_COMMIT_TRANS;
   sql_command_flags[SQLCOM_OPTIMIZE]|= CF_WRITE_LOGS_COMMAND | CF_AUTO_COMMIT_TRANS;
   sql_command_flags[SQLCOM_ANALYZE]=   CF_WRITE_LOGS_COMMAND | CF_AUTO_COMMIT_TRANS;
+  sql_command_flags[SQLCOM_CHECK]=     CF_WRITE_LOGS_COMMAND | CF_AUTO_COMMIT_TRANS;
 
   sql_command_flags[SQLCOM_CREATE_USER]|=       CF_AUTO_COMMIT_TRANS;
   sql_command_flags[SQLCOM_DROP_USER]|=         CF_AUTO_COMMIT_TRANS;
@@ -414,7 +415,6 @@ void init_update_queries(void)
 
   sql_command_flags[SQLCOM_FLUSH]=              CF_AUTO_COMMIT_TRANS;
   sql_command_flags[SQLCOM_RESET]=              CF_AUTO_COMMIT_TRANS;
-  sql_command_flags[SQLCOM_CHECK]=              CF_AUTO_COMMIT_TRANS;
   sql_command_flags[SQLCOM_CREATE_SERVER]=      CF_AUTO_COMMIT_TRANS;
   sql_command_flags[SQLCOM_ALTER_SERVER]=       CF_AUTO_COMMIT_TRANS;
   sql_command_flags[SQLCOM_DROP_SERVER]=        CF_AUTO_COMMIT_TRANS;