drop table if exists t1,t2; create table t1 ( n int auto_increment primary key); lock tables t1 write; insert into t1 values(NULL); unlock tables; check table t1; Table Op Msg_type Msg_text test.t1 check status OK lock tables t1 write, t1 as t0 read; insert into t1 values(NULL); unlock tables; check table t1; Table Op Msg_type Msg_text test.t1 check status OK lock tables t1 write, t1 as t0 read, t1 as t2 read; insert into t1 values(NULL); unlock tables; check table t1; Table Op Msg_type Msg_text test.t1 check status OK lock tables t1 write, t1 as t0 write, t1 as t2 read; insert into t1 values(NULL); unlock tables; check table t1; Table Op Msg_type Msg_text test.t1 check status OK lock tables t1 write, t1 as t0 write, t1 as t2 read, t1 as t3 read; insert into t1 values(NULL); unlock tables; check table t1; Table Op Msg_type Msg_text test.t1 check status OK lock tables t1 write, t1 as t0 write, t1 as t2 write; insert into t1 values(NULL); unlock tables; check table t1; Table Op Msg_type Msg_text test.t1 check status OK drop table t1; CREATE TABLE t1 (a int); CREATE TABLE t2 (a int); lock tables t1 write,t1 as b write, t2 write, t2 as c read; drop table t1,t2; CREATE TABLE t1 (a int); CREATE TABLE t2 (a int); lock tables t1 write,t1 as b write, t2 write, t2 as c read; drop table t2,t1; unlock tables; create temporary table t1(f1 int); lock tables t1 write; insert into t1 values (1); show columns from t1; Field Type Null Key Default Extra f1 int(11) YES NULL insert into t1 values(2); drop table t1; unlock tables;