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stop slave;
drop table if exists t1,t2,t3,t4,t5,t6,t7,t8,t9;
reset master;
reset slave;
drop table if exists t1,t2,t3,t4,t5,t6,t7,t8,t9;
start slave;
create table t1(n int);
insert into t1 values(get_lock("lock",2));
select get_lock("lock",2);
get_lock("lock",2)
1
select release_lock("lock");
release_lock("lock")
1
select get_lock("lock",3);
get_lock("lock",3)
1
select * from t1;
n
1
select is_free_lock("lock"), is_used_lock("lock") = connection_id();
is_free_lock("lock") is_used_lock("lock") = connection_id()
0 1
explain extended select is_free_lock("lock"), is_used_lock("lock");
id select_type table type possible_keys key key_len ref rows filtered Extra
1 SIMPLE NULL NULL NULL NULL NULL NULL NULL NULL No tables used
Warnings:
Note 1003 select is_free_lock('lock') AS `is_free_lock("lock")`,is_used_lock('lock') AS `is_used_lock("lock")`
select is_free_lock("lock2");
is_free_lock("lock2")
1
select is_free_lock(NULL);
is_free_lock(NULL)
NULL
drop table t1;
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