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SET @save_stats_persistent=@@GLOBAL.innodb_stats_persistent;
SET GLOBAL innodb_stats_persistent=OFF;
#
# MDEV-6402: Optimizer doesn't choose best execution plan when composite key is used
#
CREATE TABLE t2 (
pk1 int(11) NOT NULL,
pk2 int(11) NOT NULL,
fd5 bigint(20) DEFAULT NULL,
filler1 char(200),
filler2 char(200),
PRIMARY KEY (pk1,pk2),
UNIQUE KEY ux_pk1_fd5 (pk1,fd5)
) ENGINE=InnoDB;
insert into t2
select
round(log(2,seq+1)),
seq,
seq,
REPEAT('filler-data-', 10),
REPEAT('filler-data-', 10)
from
seq_0_to_1999;
analyze table t2 persistent for all;
Table Op Msg_type Msg_text
test.t2 analyze status Engine-independent statistics collected
test.t2 analyze status OK
select pk1, count(*) from t2 group by pk1;
pk1 count(*)
0 1
1 1
2 3
3 6
4 11
5 23
6 45
7 91
8 181
9 362
10 724
11 552
# The following should use range(ux_pk1_fd5), two key parts (key_len=5+8=13)
EXPLAIN SELECT * FROM t2 USE INDEX(ux_pk1_fd5) WHERE pk1=9 AND fd5 < 500 ORDER BY fd5 DESC LIMIT 10;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t2 range ux_pk1_fd5 ux_pk1_fd5 13 NULL 138 Using where
# This also must use range, not ref. key_len must be 13
EXPLAIN SELECT * FROM t2 WHERE pk1=9 AND fd5 < 500 ORDER BY fd5 DESC LIMIT 10;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t2 range PRIMARY,ux_pk1_fd5 ux_pk1_fd5 13 NULL 138 Using where
drop table t2;
#
# MDEV-6814: Server crashes in calculate_key_len on query with ORDER BY
#
CREATE TABLE t1 (f1 INT, f2 INT, f3 INT, KEY(f2),KEY(f2,f1)) ENGINE=MyISAM;
INSERT INTO t1 VALUES (1,5,0),(2,6,0);
SELECT * FROM t1 WHERE f1 < 3 AND f2 IS NULL ORDER BY f1;
f1 f2 f3
DROP TABLE t1;
#
# MDEV-6796: Unable to skip filesort when using implicit extended key
#
CREATE TABLE t1 (
pk1 int(11) NOT NULL,
pk2 varchar(64) NOT NULL,
col1 varchar(16) DEFAULT NULL,
PRIMARY KEY (pk1,pk2),
KEY key1 (pk1,col1)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
CREATE TABLE t2 (
pk1 int(11) NOT NULL,
pk2 varchar(64) NOT NULL,
col1 varchar(16) DEFAULT NULL,
PRIMARY KEY (pk1,pk2),
KEY key1 (pk1,col1,pk2)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
INSERT INTO `t1` VALUES
(12321321,'a8f5f167f44f4964e6c998dee827110c','video'),
(12321321,'d77a17a3659ffa60c54e0ea17b6c6d16','video'),
(12321321,'wwafdsafdsafads','video'),
(12321321,'696aa249f0738e8181957dd57c2d7d0b','video-2014-09-23'),
(12321321,'802f9f29584b486f356693e3aa4ef0af','video=sdsd'),
(12321321,'2f94543ff74aab82e9a058b4e8316d75','video=sdsdsds'),
(12321321,'c1316b9df0d203fd1b9035308de52a0a','video=sdsdsdsdsd');
insert into t2 select * from t1;
# this must not use filesort:
explain SELECT pk2
FROM t1 USE INDEX(key1)
WHERE pk1 = 123
AND col1 = 'video'
ORDER BY pk2 DESC LIMIT 21;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref key1 key1 55 const,const 1 Using where; Using index
# this must not use filesort, either:
explain SELECT pk2
FROM t2 USE INDEX(key1)
WHERE pk1 = 123 AND col1 = 'video'
ORDER BY pk2 DESC LIMIT 21;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t2 ref key1 key1 55 const,const 1 Using where; Using index
drop table t1, t2;
SET GLOBAL innodb_stats_persistent=@save_stats_persistent;