connect locker,localhost,root,,;
connect locker2,localhost,root,,;
connect reader,localhost,root,,;
connect writer,localhost,root,,;
connection locker;
create table t1(n int);
insert into t1 values (1 );
connection locker2;
select get_lock("mysqltest_lock" , 100 );
get_lock("mysqltest_lock" , 100 )
1
connection locker;
update t1 set n = 2 and get_lock('mysqltest_lock' , 100 );
connection writer;
update low_priority t1 set n = 4 ;
connection reader;
select n from t1;
connection locker2;
select release_lock("mysqltest_lock" );
release_lock("mysqltest_lock" )
1
connection locker;
select release_lock("mysqltest_lock" );
release_lock("mysqltest_lock" )
1
connection writer;
connection reader;
n
4
drop table t1;
connection locker;
create table t1(n int);
insert into t1 values (1 ),(2 );
connection locker2;
select get_lock("mysqltest_lock" , 100 );
get_lock("mysqltest_lock" , 100 )
1
connection locker;
select n from t1 where get_lock('mysqltest_lock' , 100 );
connection writer;
update low_priority t1 set n = 4 ;
connection reader;
select n from t1;
n
1
2
connection locker2;
select release_lock("mysqltest_lock" );
release_lock("mysqltest_lock" )
1
connection locker;
n
1
2
select release_lock("mysqltest_lock" );
release_lock("mysqltest_lock" )
1
connection writer;
drop table t1;
connection locker;
create table t1 (a int, b int);
create table t2 (c int, d int);
insert into t1 values(1 ,1 );
insert into t1 values(2 ,2 );
insert into t2 values(1 ,2 );
lock table t1 read;
connection writer;
update t1,t2 set c=a where b=d;
connection reader;
select c from t2;
c
2
connection locker;
unlock tables;
drop table t1;
drop table t2;
connection locker;
create table t1 (a int);
create table t2 (a int);
lock table t1 write, t2 write;
connection reader;
insert t1 select * from t2;
connection locker;
drop table t2;
unlock tables;
connection reader;
ERROR 42 S02: Table 'test.t2' doesn't exist
connection locker;
drop table t1;
connection locker;
create table t1 (a int);
create table t2 (a int);
lock table t1 write, t2 write, t1 as t1_2 write, t2 as t2_2 write;
connection reader;
insert t1 select * from t2;
connection locker;
drop table t2;
unlock tables;
connection reader;
ERROR 42 S02: Table 'test.t2' doesn't exist
connection locker;
drop table t1;
End of 4 .1 tests
create table t1(a int);
lock tables t1 write;
connection reader;
show columns from t1;
Field Type Null Key Default Extra
a int(11 ) YES NULL
connection locker;
unlock tables;
drop table t1;
connection locker;
USE mysql;
LOCK TABLES columns_priv WRITE, db WRITE, user WRITE;
FLUSH TABLES;
connection reader;
USE mysql;
SELECT global_priv.host FROM global_priv, db WHERE global_priv.user = db.user LIMIT 1 ;
connection locker;
OPTIMIZE TABLES columns_priv, db, global_priv;
Table Op Msg_type Msg_text
mysql.columns_priv optimize status OK
mysql.db optimize status OK
mysql.global_priv optimize status OK
UNLOCK TABLES;
connection reader;
host
USE test;
connection locker;
use test;
connection default;
connection writer;
CREATE TABLE t1 (c1 int);
LOCK TABLE t1 WRITE;
connection locker;
FLUSH TABLES WITH READ LOCK;
connection writer;
CREATE TABLE t2 (c1 int);
ERROR HY000: Table 't2' was not locked with LOCK TABLES
UNLOCK TABLES;
connection locker;
UNLOCK TABLES;
connection default;
DROP TABLE t1;
connection writer;
CREATE TABLE t1 (c1 int);
LOCK TABLE t1 WRITE;
connection locker;
FLUSH TABLES WITH READ LOCK;
connection writer;
CREATE TABLE t2 AS SELECT * FROM t1;
ERROR HY000: Table 't2' was not locked with LOCK TABLES
UNLOCK TABLES;
connection locker;
UNLOCK TABLES;
connection default;
DROP TABLE t1;
connect con1,localhost,root,,;
connect con2,localhost,root,,;
connection con1;
CREATE DATABASE mysqltest_1;
FLUSH TABLES WITH READ LOCK;
connection con2;
DROP DATABASE mysqltest_1;
connection con1;
DROP DATABASE mysqltest_1;
ERROR HY000: Can't execute the query because you have a conflicting read lock
UNLOCK TABLES;
connection con2;
connection default;
disconnect con1;
disconnect con2;
DROP DATABASE mysqltest_1;
ERROR HY000: Can't drop database ' mysqltest_1'; database doesn't exist
connection locker;
create table t1 (f1 int(12 ) unsigned not null auto_increment, primary key(f1));
lock tables t1 write;
connection writer;
alter table t1 auto_increment=0 ;
connection reader;
alter table t1 auto_increment=0 ;
connection locker;
unlock tables;
connection writer;
connection reader;
connection locker;
drop table t1;
connect con1,localhost,root,,;
connect con2,localhost,root,,;
connect con3,localhost,root,,;
connect con4,localhost,root,,;
connect con5,localhost,root,,;
create table t1 (a int);
create table t2 like t1;
connection con1;
lock tables t1 write;
connection con2;
flush tables with read lock;
connection con5;
# global read lock is taken
connection con3;
select * from t2 for update;
connection con5;
# waiting for release of read lock
connection con4;
# would hang and later cause a deadlock
flush tables t2;
connection con1;
# clean up
unlock tables;
connection con2;
unlock tables;
connection con3;
a
connection con4;
connection default;
disconnect con5;
disconnect con4;
disconnect con3;
disconnect con2;
disconnect con1;
drop table t1,t2;
#
# Lightweight version:
# Ensure that the wait for a GRL is done before opening tables.
#
connect con1,localhost,root,,;
connect con2,localhost,root,,;
create table t1 (a int);
create table t2 like t1;
#
# UPDATE
#
connection default;
flush tables with read lock;
connection con1;
update t2 set a = 1 ;
connection default;
# statement is waiting for release of read lock
connection con2;
flush table t2;
connection default;
unlock tables;
connection con1;
connection con2;
#
# LOCK TABLES .. WRITE
#
connection default;
flush tables with read lock;
connection con1;
lock tables t2 write;
connection default;
# statement is waiting for release of read lock
connection con2;
flush table t2;
connection default;
unlock tables;
connection con1;
unlock tables;
connection default;
disconnect con2;
disconnect con1;
drop table t1,t2;
End of 5 .0 tests
create table t1 (i int);
connection locker;
lock table t1 read;
connection writer;
update t1 set i= 10 ;
connection reader;
select * from t1;
connection default;
kill query ID;
connection reader;
i
connection writer;
ERROR 70100 : Query execution was interrupted
connection locker;
unlock tables;
connection default;
drop table t1;
disconnect locker;
disconnect locker2;
disconnect reader;
disconnect writer;
create table t1 (i int);
connect flush,localhost,root,,test,,;
connection default;
lock tables t1 write;
connection flush;
flush tables with read lock;;
connection default;
alter table t1 add column j int;
connect insert,localhost,root,,test,,;
connection insert;
insert into t1 values (1 ,2 );
connection default;
unlock tables;
connection flush;
select * from t1;
i j
unlock tables;
connection insert;
connection default;
select * from t1;
i j
1 2
drop table t1;
disconnect flush;
disconnect insert;
create table t1 (i int);
connect flush,localhost,root,,test,,;
connection default;
lock tables t1 write;
connection flush;
flush tables with read lock;;
connection default;
flush tables;
unlock tables;
connection flush;
connection default;
disconnect flush;
drop table t1;
create table t1 (a int);
flush status;
lock tables t1 read;
connect waiter,localhost,root,,;
connection waiter;
insert into t1 values(1 );
connection default;
unlock tables;
connection waiter;
connection default;
drop table t1;
disconnect waiter;
select @tlwa < @tlwb;
@tlwa < @tlwb
1
End of 5 .1 tests
create table t1 (i int);
connect flush,localhost,root,,test,,;
connection default;
lock tables t1 write;
connection flush;
flush tables with read lock;;
connection default;
flush tables;
drop table t1;
connection flush;
connection default;
disconnect flush;
#
# Test for bug #46272 "MySQL 5.4.4, new MDL: unnecessary deadlock" .
#
create table t1 (c1 int primary key, c2 int, c3 int);
insert into t1 values (1 ,1 ,0 ),(2 ,2 ,0 ),(3 ,3 ,0 ),(4 ,4 ,0 ),(5 ,5 ,0 );
begin;
update t1 set c3=c3+1 where c2=3 ;
connect con46272,localhost,root,,test,,;
connection con46272;
# The below ALTER TABLE statement should wait till transaction
# in connection 'default' is complete and then succeed.
# It should not deadlock or fail with ER_LOCK_DEADLOCK error .
# Sending:
alter table t1 add column c4 int;;
connection default;
# Wait until the above ALTER TABLE gets blocked because this
# connection holds SW metadata lock on table to be altered.
# The below statement should succeed. It should not
# deadlock or end with ER_LOCK_DEADLOCK error .
update t1 set c3=c3+1 where c2=4 ;
# Unblock ALTER TABLE by committing transaction.
commit;
connection con46272;
# Reaping ALTER TABLE.
connection default;
disconnect con46272;
drop table t1;
#
# Bug#47249 assert in MDL_global_lock::is_lock_type_compatible
#
#
# Test 1 : LOCK TABLES v1 WRITE, t1 READ;
#
CREATE TABLE t1 ( f1 integer );
CREATE VIEW v1 AS SELECT f1 FROM t1 ;
# Connection 2
connect con2,localhost,root;
LOCK TABLES v1 WRITE, t1 READ;
FLUSH TABLE t1;
disconnect con2;
# Connection 1
connection default;
LOCK TABLES t1 WRITE;
FLUSH TABLE t1;
DROP TABLE t1;
DROP VIEW v1;
#
# Test 2 : LOCK TABLES t1 WRITE, v1 READ;
#
CREATE TABLE t1 ( f1 integer );
CREATE VIEW v1 AS SELECT f1 FROM t1 ;
connect con2,localhost,root;
LOCK TABLES t1 WRITE, v1 READ;
FLUSH TABLE t1;
disconnect con2;
connection default;
LOCK TABLES t1 WRITE;
FLUSH TABLE t1;
DROP TABLE t1;
DROP VIEW v1;
#
# Test for bug #50913 "Deadlock between open_and_lock_tables_derived
# and MDL". Also see additional coverage in mdl_sync.test.
#
connect con50913,localhost,root;
connection default;
create table t1 (i int);
create view v1 as select i from t1;
begin;
select * from t1;
i
connection con50913;
# Sending:
alter table t1 add column j int;
connection default;
# Wait until ALTER TABLE gets blocked.
# The below statement should try to acquire SW lock on 't1'
# and therefore should get ER_LOCK_DEADLOCK error . Before
# bug fix it acquired SR lock and hung on thr_lock.c lock.
delete a from t1 as a where i = 1 ;
ERROR 40001 : Deadlock found when trying to get lock; try restarting transaction
# Unblock ALTER TABLE.
commit;
connection con50913;
# Reaping ALTER TABLE;
connection default;
begin;
select * from v1;
i
connection con50913;
# Sending:
alter table t1 drop column j;
connection default;
# Wait until ALTER TABLE gets blocked.
# The below statement should try to acquire SW lock on 't1'
# and therefore should get ER_LOCK_DEADLOCK error . Before
# bug fix it acquired SR lock and hung on thr_lock.c lock.
insert into v1 values (1 );
ERROR 40001 : Deadlock found when trying to get lock; try restarting transaction
# Unblock ALTER TABLE.
commit;
connection con50913;
# Reaping ALTER TABLE;
connection default;
disconnect con50913;
drop view v1;
drop table t1;
#
# Bug#45225 Locking: hang if drop table with no timeout
#
# These tests also provide function coverage for the
# lock_wait_timeout server variable.
#
CREATE TABLE t1 (id int);
connect con2, localhost, root,,;
SET SESSION lock_wait_timeout= 1 ;
#
# Test 1 : acquire exclusive lock
#
connection default;
START TRANSACTION;
INSERT INTO t1 VALUES (1 );
connection con2;
DROP TABLE t1;
ERROR HY000: Lock wait timeout exceeded; try restarting transaction
connection default;
COMMIT;
#
# Test 2 : upgrade shared lock
#
connection default;
START TRANSACTION;
SELECT * FROM t1;
id
1
connection con2;
ALTER TABLE t1 RENAME TO t2;
ERROR HY000: Lock wait timeout exceeded; try restarting transaction
connection default;
COMMIT;
#
# Test 3 : acquire shared lock
#
connection default;
LOCK TABLE t1 WRITE;
connection con2;
INSERT INTO t1(id) VALUES (2 );
ERROR HY000: Lock wait timeout exceeded; try restarting transaction
connection default;
UNLOCK TABLES;
#
# Test 4 : table level locks
#
connection default;
LOCK TABLE t1 READ;
connection con2;
INSERT INTO t1(id) VALUES(4 );
ERROR HY000: Lock wait timeout exceeded; try restarting transaction
connection default;
UNLOCK TABLES;
#
# Test 5 : Waiting on Table Definition Cache (TDC)
#
connect con3, localhost, root;
connection default;
LOCK TABLE t1 READ;
connection con3;
FLUSH TABLES;
# Sending:
FLUSH TABLES t1;
connection con2;
SELECT * FROM t1;
ERROR HY000: Lock wait timeout exceeded; try restarting transaction
connection default;
UNLOCK TABLES;
connection con3;
# Reaping: FLUSH TABLES
#
# Test 6 : Timeouts in I_S queries
#
connection default;
CREATE TABLE t2 (id INT);
LOCK TABLE t2 WRITE;
connection con3;
# Sending:
DROP TABLE t1, t2;
connection con2;
SELECT table_name, table_comment FROM information_schema.tables
WHERE table_schema= 'test' AND table_name= 't1' ;
table_name table_comment
t1 Lock wait timeout exceeded; try restarting transaction
Warnings:
Warning 1205 Lock wait timeout exceeded; try restarting transaction
connection default;
UNLOCK TABLES;
connection con3;
# Reaping: DROP TABLE t1, t2
connection default;
# Cleanup
disconnect con2;
disconnect con3;
#
# Test for bug #51134 "Crash in MDL_lock::destroy on a concurrent
# DDL workload".
#
connect con1, localhost, root, , ;
connect con2, localhost, root, , ;
connection default;
create table t3 (i int);
connection con1;
# Lock 't3' so upcoming RENAME is blocked.
lock table t3 read;
connection con2;
# Remember ID for this connection.
# Start statement which will try to acquire two instances
# of X metadata lock on the same object.
# Sending:
rename tables t1 to t2, t2 to t3;;
connection default;
# Wait until RENAME TABLE is blocked on table 't3' .
# Kill RENAME TABLE.
kill query ID;
connection con2;
# RENAME TABLE should be aborted but should not crash.
ERROR 70100 : Query execution was interrupted
connection con1;
unlock tables;
connection default;
disconnect con1;
disconnect con2;
drop table t3;
#
# Test for the bug where upgradable metadata locks was acquired
# even if the table to altered was temporary.
# Bug found while working on the related bug #51240 .
#
CREATE TABLE t1 (id INT);
LOCK TABLE t1 WRITE;
connect con1, localhost, root;
CREATE TEMPORARY TABLE t1 (id INT);
ALTER TABLE t1 ADD COLUMN j INT;
connection default;
disconnect con1;
UNLOCK TABLES;
DROP TABLE t1;
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