mariadb/mysql-test/t/limit.test

#
# Test of update and delete with limit
#

--disable_warnings
drop table if exists t1;
--enable_warnings

create table t1 (a int not null default 0 primary key, b int not null default 0);
insert into t1 () values ();		# Testing default values
insert into t1 values (1,1),(2,1),(3,1);
update t1 set a=4 where b=1 limit 1;
select * from t1;
update t1 set b=2 where b=1 limit 2;
select * from t1;
update t1 set b=4 where b=1;
select * from t1;
delete from t1 where b=2 limit 1;
select * from t1;
delete from t1 limit 1;
select * from t1;
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;
drop table t1;

# LIMIT 0

select 0 limit 0;

#
# Test with DELETE, ORDER BY and limit (bug #1024)
#

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; 
DELETE FROM t1 WHERE id2 = 0 ORDER BY id LIMIT 1; 
# should have deleted WHERE id=2 
SELECT * FROM t1; 
DELETE FROM t1 WHERE id2 = 0 ORDER BY id desc LIMIT 1; 
SELECT * FROM t1;
DROP TABLE t1;

#
# Bug#8023 - limit on UNION with from DUAL, causes syntax error
#
create table t1 (a integer);
insert into t1 values (1);
# both queries must return one row
select 1 as a from t1 union all select 1 from dual limit 1;
(select 1 as a from t1) union all (select 1 from dual) limit 1;
drop table t1;

#
# Bug #21787: COUNT(*) + ORDER BY + LIMIT returns wrong result
#
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;
select count(*) c FROM t1 WHERE a > 0 ORDER BY c LIMIT 3;
explain select sum(a) c FROM t1 WHERE a > 0 ORDER BY c LIMIT 3;
select sum(a) c FROM t1 WHERE a > 0 ORDER BY c LIMIT 3;

# End of 4.1 tests