B4BY.588

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Filename : limit.test
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#
# 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;
drop table t1;
# End of 4.1 tests

#
# Bug #28464: a string argument to 'limit ?' PS
#

prepare s from "select 1 limit ?";
set @a='qwe';
execute s using @a;
set @a=-1;
--error ER_WRONG_ARGUMENTS
execute s using @a;
prepare s from "select 1 limit 1, ?";
--error ER_WRONG_ARGUMENTS
execute s using @a;
prepare s from "select 1 limit ?, ?";
--error ER_WRONG_ARGUMENTS
execute s using @a, @a;
set @a=14632475938453979136;
execute s using @a, @a;
set @a=-14632475938453979136;
--error ER_WRONG_ARGUMENTS
execute s using @a, @a;

--echo End of 5.0 tests

#
# Bug#37075: offset of limit clause might be truncated to 0 on 32-bits server w/o big tables
#

select 1 as a limit 4294967296,10;

--echo End of 5.1 tests

#
# Bug #27998526 : FORCE INDEX DOESN'T TAKE EFFECT WHEN A QUERY HAS GROUP_BY,
# ORDER_BY, AND LIMIT
#


CREATE TABLE t1 (id INT NOT NULL AUTO_INCREMENT,
                 k INT,
                 payload CHAR(100),
                 PRIMARY KEY(id),
                 KEY idx_k (k));

INSERT INTO t1(k) VALUES (1), (2), (3), (4), (5), (6), (7), (8), (9), (10);
ANALYZE TABLE t1;

#problem query
let query1= SELECT * FROM t1 FORCE INDEX (idx_k)
  WHERE k BETWEEN 2 AND 5
  GROUP BY id
  ORDER BY id LIMIT 0,1;

# no order by
let query2= SELECT * FROM t1 FORCE INDEX (idx_k)
  WHERE k BETWEEN 2 AND 5
  GROUP BY id
  LIMIT 0,1;

#no group by
let query3= SELECT * FROM t1 FORCE INDEX (idx_k)
  WHERE k BETWEEN 2 AND 5
  ORDER BY id LIMIT 0,1;

#no limit
let query4= SELECT * FROM t1 FORCE INDEX (idx_k)
  WHERE k BETWEEN 2 AND 5
  GROUP BY id
  ORDER BY id;

eval EXPLAIN $query1;
eval EXPLAIN $query2;
eval EXPLAIN $query3;
eval EXPLAIN $query4;

eval $query1;
eval $query2;
eval $query3;
eval $query4;

DROP TABLE t1;