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drop table if exists t0,t1,t2,t3;
#
# MDEV-6434: Wrong result (extra rows) with ORDER BY, multiple-column index, InnoDB
#
CREATE TABLE t1 (a INT, b INT, c INT, d TEXT, KEY idx(a,b,c)) ENGINE=InnoDB;
INSERT INTO t1 (a,c) VALUES
(8, 9),(8, 10),(13, 15),(16, 17),(16, 18),(16, 19),(20, 21),
(20, 22),(20, 24),(20, 25),(20, 26),(20, 27),(20, 28);
SELECT * FROM t1 WHERE a = 8 AND (b = 1 OR b IS NULL) ORDER BY c;
a b c d
8 NULL 9 NULL
8 NULL 10 NULL
DROP TABLE t1;
#
# MDEV-9457: Poor query plan chosen for ORDER BY query by a recent 10.1
#
create table t0 (a int);
insert into t0 values (0),(1),(2),(3),(4),(5),(6),(7),(8),(9);
create table t1 (
pk int primary key,
key1 int,
key2 int,
col1 char(255),
key(key1),
key(key2)
) engine=innodb;
set @a=-1;
insert into t1
select
@a:=@a+1,
@a,
@a,
repeat('abcd', 63)
from t0 A, t0 B, t0 C, t0 D;
# The following must NOT use 'index' on PK.
# It should use index_merge(key1,key2) + filesort
explain
select *
from t1
where key1<3 or key2<3
order by pk;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index_merge key1,key2 key1,key2 5,5 NULL # Using sort_union(key1,key2); Using where; Using filesort
explain
select *
from t1
where key1<3 or key2<3;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index_merge key1,key2 key1,key2 5,5 NULL # Using sort_union(key1,key2); Using where
drop table t0, t1;
#
# MDEV-18094: Query with order by limit picking index scan over filesort
#
create table t0 (a int);
INSERT INTO t0 VALUES (0),(0),(0),(0),(2),(0),(0),(1),(1),(0);
CREATE TABLE t1 (
a int(11),
b int(11),
c int(11),
KEY a_c (a,c),
KEY a_b (a,b)
) ENGINE=InnoDB;
insert into t1 select A.a , B.a, C.a from t0 A, t0 B, t0 C;
# should use ref access
explain select a,b,c from t1 where a=1 and c=2 order by b;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref a_c,a_b a_c 10 const,const 20 Using where; Using filesort
# both should use range access
explain select a,b,c from t1 where a=1 and c=2 order by b limit 1000;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range a_c,a_b a_b 5 NULL 200 Using where
explain select a,b,c from t1 where a=1 and c=2 order by b limit 2000;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range a_c,a_b a_b 5 NULL 200 Using where
drop table t1,t0;
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