mariadb/mysql-test/t/truncate_coverage.test
Dmitry Lenev 218bf86cd9 Fix for bug #46785 "main.truncate_coverage fails
sporadically".

Races in truncate_coverage.test have caused its sporadical 
failures.

In the test case we have tried to kill truncate statement 
being executed in the first connection which was waiting 
for X metadata lock on table being locked by the second
connection. Since we have released metadata lock held by 
the second connection right after issuing KILL statement 
sometimes TRUNCATE TABLE managed to acquire X lock before 
it has noticed that it was killed. In this case TRUNCATE
TABLE was successfully executed till its end and this fact
has caused test failure since this statement didn't return 
expected error in such case.

This patch addresses the problem by not releasing metadata
locks in the second connections prematurely.
2010-06-11 17:32:12 +04:00

174 lines
4.2 KiB
Text

#
# Code coverage testing of TRUNCATE TABLE.
#
# Ingo Struewing, 2009-07-20
#
--source include/have_debug_sync.inc
SET DEBUG_SYNC='RESET';
--let $MYSQLD_DATADIR= `SELECT @@datadir`
--disable_warnings
DROP TABLE IF EXISTS t1;
--enable_warnings
--echo #
--echo # Bug#20667 - Truncate table fails for a write locked table
--echo #
########
# Attack wait_while_table_is_used(). Kill query while trying to
# upgrade MDL.
#
CREATE TABLE t1 (c1 INT);
INSERT INTO t1 VALUES (1);
#
# Acquire a shared metadata lock on table by opening HANDLER for it and wait.
# TRUNCATE shall block on this metadata lock.
# We can't use normal DML as such statements would also block LOCK TABLES.
#
--echo #
--echo # connection con1
--connect (con1, localhost, root,,)
HANDLER t1 OPEN;
#
# Get connection id of default connection.
# Lock the table and start TRUNCATE, which will block on MDL upgrade.
#
--echo #
--echo # connection default
--connection default
let $ID= `SELECT @id := CONNECTION_ID()`;
LOCK TABLE t1 WRITE;
SET DEBUG_SYNC='mdl_upgrade_shared_lock_to_exclusive SIGNAL waiting';
send TRUNCATE TABLE t1;
#
# Get the default connection ID into a variable in an invisible statement.
# Kill the TRUNCATE query. This shall result in an error return
# from wait_while_table_is_used().
#
--echo #
--echo # connection con2
--connect (con2, localhost, root,,)
SET DEBUG_SYNC='now WAIT_FOR waiting';
let $invisible_assignment_in_select = `SELECT @id := $ID`;
KILL QUERY @id;
--disconnect con2
--echo #
--echo # connection default
--connection default
--error ER_QUERY_INTERRUPTED
reap;
UNLOCK TABLES;
--echo #
--echo # connection con1
--connection con1
--echo # Release shared metadata lock by closing HANDLER.
HANDLER t1 CLOSE;
--disconnect con1
--echo #
--echo # connection default
--connection default
DROP TABLE t1;
SET DEBUG_SYNC='RESET';
########
# Attack reopen_tables(). Remove form file.
#
CREATE TABLE t1 (c1 INT);
INSERT INTO t1 VALUES (1);
#
# Acquire a shared metadata lock on table by opening HANDLER for it and wait.
# TRUNCATE shall block on this metadata lock.
# We can't use normal DML as such statements would also block LOCK TABLES.
#
--echo #
--echo # connection con1
--connect (con1, localhost, root,,)
HANDLER t1 OPEN;
#
# Lock the table and start TRUNCATE, which will block on MDL upgrade.
#
--echo #
--echo # connection default
--connection default
LOCK TABLE t1 WRITE;
SET DEBUG_SYNC='mdl_upgrade_shared_lock_to_exclusive SIGNAL waiting';
send TRUNCATE TABLE t1;
#
# Remove datafile.
# Commit to let TRUNCATE continue.
#
--echo #
--echo # connection con2
--connect (con2, localhost, root,,)
SET DEBUG_SYNC='now WAIT_FOR waiting';
--remove_file $MYSQLD_DATADIR/test/t1.frm
--disconnect con2
--echo #
--echo # connection con1
--connection con1
HANDLER t1 CLOSE;
--disconnect con1
--echo #
--echo # connection default
--connection default
--error ER_NO_SUCH_TABLE
reap;
UNLOCK TABLES;
--error ER_BAD_TABLE_ERROR
DROP TABLE t1;
SET DEBUG_SYNC='RESET';
########
# Attack acquire_exclusive_locks(). Hold a global read lock.
# Non-LOCK TABLE case.
#
CREATE TABLE t1 (c1 INT);
INSERT INTO t1 VALUES (1);
#
# Start a transaction and execute a DML in it. Since 5.4.4 this leaves
# a shared meta data lock (MDL) behind. TRUNCATE shall block on it.
#
--echo #
--echo # connection con1
--connect (con1, localhost, root,,)
START TRANSACTION;
INSERT INTO t1 VALUES (2);
#
# Get connection id of default connection.
# Start TRUNCATE, which will block on acquire_exclusive_locks().
#
--echo #
--echo # connection default
--connection default
let $ID= `SELECT @id := CONNECTION_ID()`;
SET DEBUG_SYNC='mdl_acquire_lock_wait SIGNAL waiting';
send TRUNCATE TABLE t1;
#
# Get the default connection ID into a variable in an invisible statement.
# Kill the TRUNCATE query. This shall result in an error return
# from wait_while_table_is_used().
#
--echo #
--echo # connection con1
--connection con1
SET DEBUG_SYNC='now WAIT_FOR waiting';
let $invisible_assignment_in_select = `SELECT @id := $ID`;
KILL QUERY @id;
--echo #
--echo # connection default
--connection default
--error ER_QUERY_INTERRUPTED
reap;
--echo #
--echo # connection con1
--connection con1
--echo # Release SW lock by committing transaction.
COMMIT;
--disconnect con1
--echo #
--echo # connection default
--connection default
UNLOCK TABLES;
DROP TABLE t1;
SET DEBUG_SYNC='RESET';