create table t(id int primary key);
insert into t values(1);
SET @old_innodb_lock_wait_timeout= @@innodb_lock_wait_timeout;
set global innodb_lock_wait_timeout=2;
begin;
select * from t where id=1 for update;
id
1
begin;
update t set id=2 where id=1;
commit;
rollback;
select * from t;
id
2
set global innodb_lock_wait_timeout= @old_innodb_lock_wait_timeout;
drop table t;