1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
|
drop table if exists t1,t3;
#
# MDEV-20611: MRR scan over partitioned InnoDB table produces "Out of memory" error
#
create table t1(a int);
insert into t1 values (0),(1),(2),(3),(4),(5),(6),(7),(8),(9);
set @tmp=@@storage_engine;
set storage_engine=InnoDB;
create table t3 (
ID bigint(20) NOT NULL AUTO_INCREMENT,
part_id int,
key_col int,
col2 int,
key(key_col),
PRIMARY KEY (ID,part_id)
) PARTITION BY RANGE (part_id)
(PARTITION p1 VALUES LESS THAN (3),
PARTITION p2 VALUES LESS THAN (7),
PARTITION p3 VALUES LESS THAN (10)
);
show create table t3;
Table Create Table
t3 CREATE TABLE `t3` (
`ID` bigint(20) NOT NULL AUTO_INCREMENT,
`part_id` int(11) NOT NULL,
`key_col` int(11) DEFAULT NULL,
`col2` int(11) DEFAULT NULL,
PRIMARY KEY (`ID`,`part_id`),
KEY `key_col` (`key_col`)
) ENGINE=InnoDB DEFAULT CHARSET=latin1
PARTITION BY RANGE (`part_id`)
(PARTITION `p1` VALUES LESS THAN (3) ENGINE = InnoDB,
PARTITION `p2` VALUES LESS THAN (7) ENGINE = InnoDB,
PARTITION `p3` VALUES LESS THAN (10) ENGINE = InnoDB)
set storage_engine= @tmp;
insert into t3 select
A.a+10*B.a,
A.a,
B.a,
123456
from t1 A, t1 B;
set optimizer_switch='mrr=on';
explain
select * from t3 force index (key_col) where key_col < 3;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t3 range key_col key_col 5 NULL # Using where; Rowid-ordered scan
select * from t3 force index (key_col) where key_col < 3;
ID part_id key_col col2
1 0 0 123456
1 1 0 123456
2 2 0 123456
10 0 1 123456
11 1 1 123456
12 2 1 123456
20 0 2 123456
21 1 2 123456
22 2 2 123456
3 3 0 123456
4 4 0 123456
5 5 0 123456
6 6 0 123456
13 3 1 123456
14 4 1 123456
15 5 1 123456
16 6 1 123456
23 3 2 123456
24 4 2 123456
25 5 2 123456
26 6 2 123456
7 7 0 123456
8 8 0 123456
9 9 0 123456
17 7 1 123456
18 8 1 123456
19 9 1 123456
27 7 2 123456
28 8 2 123456
29 9 2 123456
drop table t1,t3;
|
