drop table if exists t1,t2; drop database if exists mysqltest; create temporary table t1(n int not null primary key); create table t2(n int); insert into t2 values(3); select * from t1; n 3 flush tables with read lock; drop table t2; ERROR HY000: Can't execute the query because you have a conflicting read lock drop table t2; unlock tables; create database mysqltest; create table mysqltest.t1(n int); insert into mysqltest.t1 values (23); flush tables with read lock; drop database mysqltest; select * from mysqltest.t1; n 23 unlock tables; create table t1 (n int); flush tables with read lock; insert into t1 values (345); select * from t1; n 345 drop table t1; create table t1 (c1 int); lock table t1 write; flush tables with read lock; ERROR HY000: Can't execute the given command because you have active locked tables or an active transaction lock table t1 read; flush tables with read lock; lock table t1 write; ERROR HY000: Can't execute the query because you have a conflicting read lock lock table t1 read; lock table t1 write; ERROR HY000: Can't execute the query because you have a conflicting read lock unlock tables; create table t2 (c1 int); create table t3 (c1 int); lock table t1 read, t2 read, t3 write; flush tables with read lock; ERROR HY000: Can't execute the given command because you have active locked tables or an active transaction lock table t1 read, t2 read, t3 read; flush tables with read lock; unlock tables; drop table t1, t2, t3; create table t1 (c1 int); create table t2 (c1 int); lock table t1 write; flush tables with read lock; insert into t2 values(1); unlock tables; drop table t1, t2;