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drop table if exists t1;
create table t1 (a int not null default 0 primary key, b int not null default 0);
insert into t1 () values ();
insert into t1 values (1,1),(2,1),(3,1);
update t1 set a=4 where b=1 limit 1;
select * from t1;
a b
0 0
4 1
2 1
3 1
update t1 set b=2 where b=1 limit 2;
select * from t1;
a b
0 0
4 2
2 2
3 1
update t1 set b=4 where b=1;
select * from t1;
a b
0 0
4 2
2 2
3 4
delete from t1 where b=2 limit 1;
select * from t1;
a b
0 0
2 2
3 4
delete from t1 limit 1;
select * from t1;
a b
2 2
3 4
drop table t1;
create table t1 (i int);
insert into t1 (i) values(1),(1),(1);
delete from t1 limit 1;
update t1 set i=2 limit 1;
delete from t1 limit 0;
update t1 set i=3 limit 0;
select * from t1;
i
2
1
drop table t1;
select 0 limit 0;
0
CREATE TABLE t1(id int auto_increment primary key, id2 int, index(id2));
INSERT INTO t1 (id2) values (0),(0),(0);
DELETE FROM t1 WHERE id=1;
INSERT INTO t1 SET id2=0;
SELECT * FROM t1;
id id2
4 0
2 0
3 0
DELETE FROM t1 WHERE id2 = 0 ORDER BY id LIMIT 1;
SELECT * FROM t1;
id id2
4 0
3 0
DELETE FROM t1 WHERE id2 = 0 ORDER BY id desc LIMIT 1;
SELECT * FROM t1;
id id2
3 0
DROP TABLE t1;
create table t1 (a integer);
insert into t1 values (1);
select 1 as a from t1 union all select 1 from dual limit 1;
a
1
(select 1 as a from t1) union all (select 1 from dual) limit 1;
a
1
drop table t1;
create table t1 (a int);
insert into t1 values (1),(2),(3),(4),(5),(6),(7);
explain select count(*) c FROM t1 WHERE a > 0 ORDER BY c LIMIT 3;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 7 Using where; Using temporary
select count(*) c FROM t1 WHERE a > 0 ORDER BY c LIMIT 3;
c
7
explain select sum(a) c FROM t1 WHERE a > 0 ORDER BY c LIMIT 3;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 7 Using where; Using temporary
select sum(a) c FROM t1 WHERE a > 0 ORDER BY c LIMIT 3;
c
28
drop table t1;
prepare s from "select 1 limit ?";
set @a='qwe';
execute s using @a;
1
set @a=-1;
execute s using @a;
ERROR HY000: Incorrect arguments to EXECUTE
prepare s from "select 1 limit 1, ?";
execute s using @a;
ERROR HY000: Incorrect arguments to EXECUTE
prepare s from "select 1 limit ?, ?";
execute s using @a, @a;
ERROR HY000: Incorrect arguments to EXECUTE
set @a=14632475938453979136;
execute s using @a, @a;
1
set @a=-14632475938453979136;
execute s using @a, @a;
ERROR HY000: Incorrect arguments to EXECUTE
End of 5.0 tests
select 1 as a limit 4294967296,10;
a
End of 5.1 tests
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