drop table if exists t1,t2; create table t1(n int); insert into t1 values (1); lock tables t1 write; update low_priority t1 set n = 4; select n from t1; unlock tables; n 4 drop table t1; create table t1(n int); insert into t1 values (1); lock tables t1 read; update low_priority t1 set n = 4; select n from t1; n 1 unlock tables; drop table t1; 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; update t1,t2 set c=a where b=d; select c from t2; c 2 drop table t1; drop table t2; create table t1 (a int); create table t2 (a int); lock table t1 write, t2 write; insert t1 select * from t2; drop table t2; ERROR 42S02: Table 'test.t2' doesn't exist drop table t1; 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; insert t1 select * from t2; drop table t2; ERROR 42S02: Table 'test.t2' doesn't exist drop table t1; End of 4.1 tests create table t1(a int); lock tables t1 write; show columns from t1; Field Type Null Key Default Extra a int(11) YES NULL unlock tables; drop table t1; use mysql; LOCK TABLES columns_priv WRITE, db WRITE, host WRITE, user WRITE; FLUSH TABLES; use mysql; SELECT user.Select_priv FROM user, db WHERE user.user = db.user LIMIT 1; OPTIMIZE TABLES columns_priv, db, host, user; Table Op Msg_type Msg_text mysql.columns_priv optimize status OK mysql.db optimize status OK mysql.host optimize status OK mysql.user optimize status OK UNLOCK TABLES; Select_priv N use test; use test; CREATE TABLE t1 (c1 int); LOCK TABLE t1 WRITE; FLUSH TABLES WITH READ LOCK; CREATE TABLE t2 (c1 int); UNLOCK TABLES; UNLOCK TABLES; DROP TABLE t1, t2; CREATE TABLE t1 (c1 int); LOCK TABLE t1 WRITE; FLUSH TABLES WITH READ LOCK; CREATE TABLE t2 AS SELECT * FROM t1; ERROR HY000: Table 't2' was not locked with LOCK TABLES UNLOCK TABLES; UNLOCK TABLES; DROP TABLE t1; CREATE DATABASE mysqltest_1; FLUSH TABLES WITH READ LOCK; DROP DATABASE mysqltest_1; DROP DATABASE mysqltest_1; ERROR HY000: Can't execute the query because you have a conflicting read lock UNLOCK TABLES; DROP DATABASE mysqltest_1; ERROR HY000: Can't drop database 'mysqltest_1'; database doesn't exist create table t1 (f1 int(12) unsigned not null auto_increment, primary key(f1)) engine=innodb; lock tables t1 write; alter table t1 auto_increment=0; alter table t1 auto_increment=0; unlock tables; drop table t1; End of 5.0 tests create table t1 (i int); lock table t1 read; update t1 set i= 10;; select * from t1;; kill query ID; i ERROR 70100: Query execution was interrupted unlock tables; drop table t1; End of 5.1 tests