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drop table if exists t1,t2;
create table t1 (id int not null, f_id int not null, f int not null,
primary key(f_id, id)) engine=innodb;
create table t2 (id int not null,s_id int not null,s varchar(200),
primary key(id)) engine=innodb;
INSERT INTO t1 VALUES (8, 1, 3);
INSERT INTO t1 VALUES (1, 2, 1);
INSERT INTO t2 VALUES (1, 0, '');
INSERT INTO t2 VALUES (8, 1, '');
commit;
DELETE ml.* FROM t1 AS ml LEFT JOIN t2 AS mm ON (mm.id=ml.id)
WHERE mm.id IS NULL;
select ml.* from t1 as ml left join t2 as mm on (mm.id=ml.id)
where mm.id is null lock in share mode;
id f_id f
drop table t1,t2;
create table t1 (id int not null, f_id int not null, f int not null,
primary key(id),key(f_id)) engine=innodb;
create table t2 (id int not null,s_id int not null,s varchar(200),
primary key(id),key(s_id)) engine=innodb;
INSERT INTO t1 VALUES (8, 1, 3);
INSERT INTO t1 VALUES (1, 2, 1);
INSERT INTO t2 VALUES (1, 0, '');
INSERT INTO t2 VALUES (8, 1, '');
commit;
delete ml.* from t1 as ml left join t2 as mm on (mm.s_id=ml.f_id) where mm.s is null;
select ml.* from t1 as ml left join t2 as mm on (mm.s_id=ml.f_id) where mm.s is null lock in share mode;
id f_id f
drop table t1,t2;
create table t1(a int not null, b int, primary key(a)) engine=innodb;
insert into t1 values(1,1),(2,2),(3,1),(4,2),(5,1),(6,2);
commit;
set autocommit = 0;
select * from t1 lock in share mode;
a b
1 1
2 2
3 1
4 2
5 1
6 2
update t1 set b = 5 where b = 1;
set autocommit = 0;
select * from t1 where a = 2 and b = 2 for update;
ERROR HY000: Lock wait timeout exceeded; try restarting transaction
commit;
commit;
drop table t1;
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