drop table if exists t1,t2; connect a,localhost,root,,; connect b,localhost,root,,; connection a; set binlog_format=mixed; set session transaction isolation level repeatable read; create table t1(a int not null) engine=innodb DEFAULT CHARSET=latin1; insert into t1 values (1),(2),(3),(4),(5),(6),(7); set autocommit=0; select * from t1 where a=3 lock in share mode; a 3 connection b; set binlog_format=mixed; set session transaction isolation level repeatable read; set autocommit=0; update t1 set a=10 where a=5; ERROR HY000: Lock wait timeout exceeded; try restarting transaction commit; connection a; commit; connection b; set session transaction isolation level read committed; update t1 set a=10 where a=5; connection a; select * from t1 where a=2 for update; ERROR HY000: Lock wait timeout exceeded; try restarting transaction select * from t1 where a=2 limit 1 for update; a 2 connection b; update t1 set a=11 where a=6; update t1 set a=12 where a=2; ERROR HY000: Lock wait timeout exceeded; try restarting transaction update t1 set a=13 where a=1; ERROR HY000: Lock wait timeout exceeded; try restarting transaction connection a; commit; connection b; update t1 set a=14 where a=1; commit; connection a; select * from t1; a 14 2 3 4 10 11 7 drop table t1; connection default; disconnect a; disconnect b; create table t1 (a int, b int) engine=myisam; create table t2 (c int, d int, key (c)) engine=innodb; insert into t1 values (1,1); insert into t2 values (1,2); connect a,localhost,root,,; connection a; set session transaction isolation level read committed; delete from t1 using t1 join t2 on t1.a = t2.c where t2.d in (1); connection default; disconnect a; drop table t1, t2;