# # 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 STATS_PERSISTENT=0; 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 t1 ( pk int primary key, key1 int, key2 int, col1 char(255), key(key1), key(key2) ) engine=innodb stats_persistent=0; insert into t1 select seq,seq,seq,repeat('abcd', 63) from seq_0_to_9999; # 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 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; select count(*) from t1; count(*) 1000 select count(*) from t1 where a=1; count(*) 200 select count(*) from t1 where a=1 and c=2; count(*) 20 # 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 # all should use range access explain select a,b,c from t1 where a=1 and c=2 order by b limit 10; 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 explain select a,b,c from t1 where a=1 and c=2 order by b limit 300; 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 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 ref a_c,a_b a_c 10 const,const 20 Using where; Using filesort drop table t1,t0; # Start of 10.2 tests # # MDEV-14071: wrong results with orderby_uses_equalities=on # (duplicate of MDEV-13994) # CREATE TABLE t1 (i int, j int, z int,PRIMARY KEY (i,j), KEY (z)) ENGINE=InnoDB STATS_PERSISTENT=0; CREATE TABLE t2 (i int, j int, PRIMARY KEY (i,j)) ENGINE=InnoDB STATS_PERSISTENT=0; CREATE TABLE t3 (j int, n varchar(5), PRIMARY KEY (j)) ENGINE=InnoDB STATS_PERSISTENT=0; INSERT INTO t1 VALUES (127,0,1),(188,0,1),(206,0,1),(218,0,1),(292,0,1),(338,0,1),(375,0,1), (381,0,1),(409,0,1),(466,0,1),(469,0,1),(498,0,1),(656,0,1); INSERT INTO t1 VALUES (77,4,0),(86,7,0),(96,6,0),(96,7,0),(99,9,0),(99,10,0),(99,11,0),(104,4,0), (106,5,0),(148,6,0),(177,6,0),(181,5,0),(188,8,0),(218,8,0),(253,7,0), (268,4,0),(338,4,0),(409,7,0),(466,8,0),(469,8,0),(498,8,0),(656,8,0); INSERT INTO t2 VALUES (127,7),(188,8),(188,9),(206,6),(218,8),(218,9),(292,7),(338,4),(338,5), (375,6),(381,5),(409,7),(409,8),(466,8),(466,9),(469,8),(469,9),(498,8), (498,9),(656,8),(656,9); INSERT INTO t3 VALUES (4,'four'),(5,'five'),(6,'six'),(7,'seven'),(8,'eight'),(9,'nine'); SET @save_optimizer_switch=@@optimizer_switch; SET optimizer_switch='orderby_uses_equalities=off'; SELECT i,n FROM t1 INNER JOIN t2 USING (i,j) LEFT JOIN t3 USING (j) WHERE i IN (SELECT i FROM t1 WHERE z=1) AND z=0 ORDER BY i; i n 188 eight 218 eight 338 four 409 seven 466 eight 469 eight 498 eight 656 eight SELECT i,n FROM t1 x INNER JOIN t2 USING (i,j) LEFT JOIN t3 USING (j) WHERE EXISTS (SELECT * FROM t1 WHERE i=x.i AND z=1) AND z=0 ORDER BY i; i n 188 eight 218 eight 338 four 409 seven 466 eight 469 eight 498 eight 656 eight SET optimizer_switch='orderby_uses_equalities=on'; SELECT i,n FROM t1 INNER JOIN t2 USING (i,j) LEFT JOIN t3 USING (j) WHERE i IN (SELECT i FROM t1 WHERE z=1) AND z=0 ORDER BY i; i n 188 eight 218 eight 338 four 409 seven 466 eight 469 eight 498 eight 656 eight SELECT i,n FROM t1 x INNER JOIN t2 USING (i,j) LEFT JOIN t3 USING (j) WHERE EXISTS (SELECT * FROM t1 WHERE i=x.i AND z=1) AND z=0 ORDER BY i; i n 188 eight 218 eight 338 four 409 seven 466 eight 469 eight 498 eight 656 eight set optimizer_switch= @save_optimizer_switch; DROP TABLE t1,t2,t3; # # MDEV-25858: Query results are incorrect when indexes are added # CREATE TABLE t1 (id int NOT NULL PRIMARY KEY) engine=innodb STATS_PERSISTENT=0; insert into t1 values (1),(2),(3); CREATE TABLE t2 ( id int NOT NULL PRIMARY KEY, id2 int NOT NULL, d1 datetime, d2 timestamp NOT NULL, KEY id2 (id2) ) engine=innodb stats_persistent=0; insert into t2 values (1,2,'2019-03-05 00:00:00','2019-03-06 00:00:00'), (2,3,'2019-03-05 00:00:00','2019-03-06 00:00:00'), (3,3,'2019-03-06 00:00:00','2019-03-05 00:00:00'); select t1.id,t2.id from t1 left join t2 on t2.id2 = t1.id and t2.id = (select dd.id from t2 dd where dd.id2 = t1.id and d1 > '2019-02-06 00:00:00' order by dd.d1 desc, dd.d2 desc, dd.id desc limit 1 ); id id 1 NULL 2 1 3 3 create index for_latest_sort on t2 (d1, d2, id); select t1.id,t2.id from t1 left join t2 on t2.id2 = t1.id and t2.id = (select dd.id from t2 dd where dd.id2 = t1.id and d1 > '2019-02-06 00:00:00' order by dd.d1 desc, dd.d2 desc, dd.id desc limit 1 ); id id 1 NULL 2 1 3 3 # Now, same as above but use a DESC index CREATE TABLE t3 ( id int NOT NULL PRIMARY KEY, id2 int NOT NULL, d1 datetime, d2 timestamp NOT NULL, KEY id2 (id2) ) engine=innodb; insert into t3 values (1,2,'2019-03-05 00:00:00','2019-03-06 00:00:00'), (2,3,'2019-03-05 00:00:00','2019-03-06 00:00:00'), (3,3,'2019-03-06 00:00:00','2019-03-05 00:00:00'); create index for_latest_sort on t3 (d1 desc, d2 desc, id desc); select t1.id,t3.id from t1 left join t3 on t3.id2 = t1.id and t3.id = (select dd.id from t3 dd where dd.id2 = t1.id and d1 > '2019-02-06 00:00:00' order by dd.d1 desc, dd.d2 desc, dd.id desc limit 1 ); id id 1 NULL 2 1 3 3 # # MDEV-27270: Wrong query plan with Range Checked for Each Record and ORDER BY ... LIMIT # # This must NOT have "Range checked for each record" without any # provisions to produce rows in the required ordering: explain select t1.id,t2.id from t1 left join t2 on t2.id2 = t1.id and t2.id = (select dd.id from t2 dd where dd.id2 = t1.id and d1 > '2019-02-06 00:00:00' order by dd.d1, dd.d2, dd.id limit 1 ); id select_type table type possible_keys key key_len ref rows Extra 1 PRIMARY t1 ALL NULL NULL NULL NULL # 1 PRIMARY t2 eq_ref PRIMARY,id2 id2 8 test.t1.id,func # Using where; Using index 2 DEPENDENT SUBQUERY dd range id2,for_latest_sort for_latest_sort 6 NULL # Using where drop table t1,t2,t3; # End of 10.2 tests # # MDEV-26938 Support descending indexes internally in InnoDB # create table t1 (a int, b int, c int, key r (a desc, b asc)); insert t1 select seq % 10, seq div 10, seq from seq_1_to_55; insert t1 values (NULL, NULL, NULL), (9, NULL, NULL); explain select * from t1 force index(r) order by a,b limit 20; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 ALL NULL NULL NULL NULL 57 Using filesort explain select * from t1 force index(r) order by a desc,b limit 20; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 index NULL r 10 NULL 20 select * from t1 force index(r) order by a desc,b limit 20; a b c 9 NULL NULL 9 0 9 9 1 19 9 2 29 9 3 39 9 4 49 8 0 8 8 1 18 8 2 28 8 3 38 8 4 48 7 0 7 7 1 17 7 2 27 7 3 37 7 4 47 6 0 6 6 1 16 6 2 26 6 3 36 drop table t1;