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|
#---------------- ROR-index_merge tests -----------------------
SET SESSION STORAGE_ENGINE = MyISAM;
drop table if exists t0,t1,t2;
create table t1
(
/* Field names reflect value(rowid) distribution, st=STairs, swt= SaWTooth */
st_a int not null default 0,
swt1a int not null default 0,
swt2a int not null default 0,
st_b int not null default 0,
swt1b int not null default 0,
swt2b int not null default 0,
/* fields/keys for row retrieval tests */
key1 int,
key2 int,
key3 int,
key4 int,
/* make rows much bigger then keys */
filler1 char (200),
filler2 char (200),
filler3 char (200),
filler4 char (200),
filler5 char (200),
filler6 char (200),
/* order of keys is important */
key sta_swt12a(st_a,swt1a,swt2a),
key sta_swt1a(st_a,swt1a),
key sta_swt2a(st_a,swt2a),
key sta_swt21a(st_a,swt2a,swt1a),
key st_a(st_a),
key stb_swt1a_2b(st_b,swt1b,swt2a),
key stb_swt1b(st_b,swt1b),
key st_b(st_b),
key(key1),
key(key2),
key(key3),
key(key4)
) ;
create table t0 as select * from t1;
# Printing of many insert into t0 values (....) disabled.
alter table t1 disable keys;
# Printing of many insert into t1 select .... from t0 disabled.
# Printing of many insert into t1 (...) values (....) disabled.
alter table t1 enable keys;
select count(*) from t1;
count(*)
64801
explain select key1,key2 from t1 where key1=100 and key2=100;
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 3 Using intersect(key1,key2); Using where; Using index
select key1,key2 from t1 where key1=100 and key2=100;
key1 key2
100 100
explain select key1,key2,key3,key4,filler1 from t1 where key1=100 and key2=100 or key3=100 and key4=100;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index_merge key1,key2,key3,key4 key1,key2,key3,key4 5,5,5,5 NULL 6 Using union(intersect(key1,key2),intersect(key3,key4)); Using where
select key1,key2,key3,key4,filler1 from t1 where key1=100 and key2=100 or key3=100 and key4=100;
key1 key2 key3 key4 filler1
100 100 100 100 key1-key2-key3-key4
insert into t1 (key1, key2, key3, key4, filler1) values (100, 100, -1, -1, 'key1-key2');
insert into t1 (key1, key2, key3, key4, filler1) values (-1, -1, 100, 100, 'key4-key3');
explain select key1,key2,filler1 from t1 where key1=100 and key2=100;
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 3 Using intersect(key1,key2); Using where
select key1,key2,filler1 from t1 where key1=100 and key2=100;
key1 key2 filler1
100 100 key1-key2-key3-key4
100 100 key1-key2
explain select key1,key2 from t1 where key1=100 and key2=100;
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 3 Using intersect(key1,key2); Using where; Using index
select key1,key2 from t1 where key1=100 and key2=100;
key1 key2
100 100
100 100
explain select key1,key2,key3,key4 from t1 where key1=100 and key2=100 or key3=100 and key4=100;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index_merge key1,key2,key3,key4 key1,key2,key3,key4 5,5,5,5 NULL 6 Using union(intersect(key1,key2),intersect(key3,key4)); Using where
select key1,key2,key3,key4 from t1 where key1=100 and key2=100 or key3=100 and key4=100;
key1 key2 key3 key4
100 100 100 100
100 100 -1 -1
-1 -1 100 100
explain select key1,key2,key3,key4,filler1 from t1 where key1=100 and key2=100 or key3=100 and key4=100;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index_merge key1,key2,key3,key4 key1,key2,key3,key4 5,5,5,5 NULL 6 Using union(intersect(key1,key2),intersect(key3,key4)); Using where
select key1,key2,key3,key4,filler1 from t1 where key1=100 and key2=100 or key3=100 and key4=100;
key1 key2 key3 key4 filler1
100 100 100 100 key1-key2-key3-key4
100 100 -1 -1 key1-key2
-1 -1 100 100 key4-key3
explain select key1,key2,key3 from t1 where key1=100 and key2=100 and key3=100;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index_merge key1,key2,key3 key1,key2 5,5 NULL 3 Using intersect(key1,key2); Using where
select key1,key2,key3 from t1 where key1=100 and key2=100 and key3=100;
key1 key2 key3
100 100 100
insert into t1 (key1,key2,key3,key4,filler1) values (101,101,101,101, 'key1234-101');
explain select key1,key2,key3,key4,filler1 from t1 where key1=100 and key2=100 or key3=101;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index_merge key1,key2,key3 key1,key2,key3 5,5,5 NULL 5 Using union(intersect(key1,key2),key3); Using where
select key1,key2,key3,key4,filler1 from t1 where key1=100 and key2=100 or key3=101;
key1 key2 key3 key4 filler1
100 100 100 100 key1-key2-key3-key4
100 100 -1 -1 key1-key2
101 101 101 101 key1234-101
select key1,key2, filler1 from t1 where key1=100 and key2=100;
key1 key2 filler1
100 100 key1-key2-key3-key4
100 100 key1-key2
update t1 set filler1='to be deleted' where key1=100 and key2=100;
update t1 set key1=200,key2=200 where key1=100 and key2=100;
delete from t1 where key1=200 and key2=200;
select key1,key2,filler1 from t1 where key2=100 and key2=200;
key1 key2 filler1
explain select key1,key2,key3,key4,filler1 from t1 where key1=100 and key2=100 or key3=100 and key4=100;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index_merge key1,key2,key3,key4 key1,key2,key3,key4 5,5,5,5 NULL 6 Using union(intersect(key1,key2),intersect(key3,key4)); Using where
select key1,key2,key3,key4,filler1 from t1 where key1=100 and key2=100 or key3=100 and key4=100;
key1 key2 key3 key4 filler1
-1 -1 100 100 key4-key3
delete from t1 where key3=100 and key4=100;
explain select key1,key2,key3,key4,filler1 from t1 where key1=100 and key2=100 or key3=100 and key4=100;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index_merge key1,key2,key3,key4 key1,key2,key3,key4 5,5,5,5 NULL 6 Using union(intersect(key1,key2),intersect(key3,key4)); Using where
select key1,key2,key3,key4,filler1 from t1 where key1=100 and key2=100 or key3=100 and key4=100;
key1 key2 key3 key4 filler1
explain select key1,key2 from t1 where key1=100 and key2=100;
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 3 Using intersect(key1,key2); Using where; Using index
select key1,key2 from t1 where key1=100 and key2=100;
key1 key2
insert into t1 (key1, key2, key3, key4, filler1) values (100, 100, 200, 200,'key1-key2-key3-key4-1');
insert into t1 (key1, key2, key3, key4, filler1) values (100, 100, 200, 200,'key1-key2-key3-key4-2');
insert into t1 (key1, key2, key3, key4, filler1) values (100, 100, 200, 200,'key1-key2-key3-key4-3');
explain select key1,key2,key3,key4,filler1 from t1 where key3=200 or (key1=100 and key2=100) or key4=200;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index_merge key1,key2,key3,key4 key3,key1,key2,key4 5,5,5,5 NULL 17 Using union(key3,intersect(key1,key2),key4); Using where
select key1,key2,key3,key4,filler1 from t1 where key3=200 or (key1=100 and key2=100) or key4=200;
key1 key2 key3 key4 filler1
100 100 200 200 key1-key2-key3-key4-2
100 100 200 200 key1-key2-key3-key4-1
100 100 200 200 key1-key2-key3-key4-3
insert into t1 (key1, key2, key3, key4, filler1) values (-1, -1, -1, 200,'key4');
explain select key1,key2,key3,key4,filler1 from t1 where key3=200 or (key1=100 and key2=100) or key4=200;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index_merge key1,key2,key3,key4 key3,key1,key2,key4 5,5,5,5 NULL 19 Using union(key3,intersect(key1,key2),key4); Using where
select key1,key2,key3,key4,filler1 from t1 where key3=200 or (key1=100 and key2=100) or key4=200;
key1 key2 key3 key4 filler1
100 100 200 200 key1-key2-key3-key4-2
100 100 200 200 key1-key2-key3-key4-1
100 100 200 200 key1-key2-key3-key4-3
-1 -1 -1 200 key4
insert into t1 (key1, key2, key3, key4, filler1) values (-1, -1, 200, -1,'key3');
explain select key1,key2,key3,key4,filler1 from t1 where key3=200 or (key1=100 and key2=100) or key4=200;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index_merge key1,key2,key3,key4 key3,key1,key2,key4 5,5,5,5 NULL 21 Using union(key3,intersect(key1,key2),key4); Using where
select key1,key2,key3,key4,filler1 from t1 where key3=200 or (key1=100 and key2=100) or key4=200;
key1 key2 key3 key4 filler1
100 100 200 200 key1-key2-key3-key4-2
100 100 200 200 key1-key2-key3-key4-1
100 100 200 200 key1-key2-key3-key4-3
-1 -1 -1 200 key4
-1 -1 200 -1 key3
explain select * from t1 where st_a=1 and st_b=1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref sta_swt12a,sta_swt1a,sta_swt2a,sta_swt21a,st_a,stb_swt1a_2b,stb_swt1b,st_b st_b 4 const 14593 Using where
explain select st_a,st_b from t1 where st_a=1 and st_b=1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index_merge sta_swt12a,sta_swt1a,sta_swt2a,sta_swt21a,st_a,stb_swt1a_2b,stb_swt1b,st_b st_a,st_b 4,4 NULL 3286 Using intersect(st_a,st_b); Using where; Using index
explain select st_a from t1 ignore index (st_a) where st_a=1 and st_b=1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref sta_swt12a,sta_swt1a,sta_swt2a,sta_swt21a,stb_swt1a_2b,stb_swt1b,st_b st_b 4 const 14593 Using where
explain select * from t1 where st_a=1 and swt1a=1 and swt2a=1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref sta_swt12a,sta_swt1a,sta_swt2a,sta_swt21a,st_a sta_swt21a 12 const,const,const 979
explain select * from t1 where st_b=1 and swt1b=1 and swt2b=1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref stb_swt1a_2b,stb_swt1b,st_b stb_swt1b 8 const,const 3891 Using where
explain select * from t1 where st_a=1 and swt1a=1 and swt2a=1 and st_b=1 and swt1b=1 and swt2b=1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index_merge sta_swt12a,sta_swt1a,sta_swt2a,sta_swt21a,st_a,stb_swt1a_2b,stb_swt1b,st_b sta_swt12a,stb_swt1a_2b 12,12 NULL 59 Using intersect(sta_swt12a,stb_swt1a_2b); Using where
explain select * from t1 ignore index (sta_swt21a, stb_swt1a_2b)
where st_a=1 and swt1a=1 and swt2a=1 and st_b=1 and swt1b=1 and swt2b=1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index_merge sta_swt12a,sta_swt1a,sta_swt2a,st_a,stb_swt1b,st_b sta_swt12a,stb_swt1b 12,8 NULL 58 Using intersect(sta_swt12a,stb_swt1b); Using where
explain select * from t1 ignore index (sta_swt21a, sta_swt12a, stb_swt1a_2b)
where st_a=1 and swt1a=1 and swt2a=1 and st_b=1 and swt1b=1 and swt2b=1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index_merge sta_swt1a,sta_swt2a,st_a,stb_swt1b,st_b sta_swt1a,sta_swt2a,stb_swt1b 8,8,8 NULL 57 Using intersect(sta_swt1a,sta_swt2a,stb_swt1b); Using where
explain select * from t1 ignore index (sta_swt21a, sta_swt12a, stb_swt1a_2b, stb_swt1b)
where st_a=1 and swt1a=1 and swt2a=1 and st_b=1 and swt1b=1 and swt2b=1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index_merge sta_swt1a,sta_swt2a,st_a,st_b sta_swt1a,sta_swt2a,st_b 8,8,4 NULL 216 Using intersect(sta_swt1a,sta_swt2a,st_b); Using where
explain select * from t1
where st_a=1 and swt1a=1 and swt2a=1 and st_b=1 and swt1b=1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index_merge sta_swt12a,sta_swt1a,sta_swt2a,sta_swt21a,st_a,stb_swt1a_2b,stb_swt1b,st_b sta_swt12a,stb_swt1a_2b 12,12 NULL 59 Using intersect(sta_swt12a,stb_swt1a_2b); Using where
explain select * from t1
where st_a=1 and swt1a=1 and st_b=1 and swt1b=1 and swt1b=1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index_merge sta_swt12a,sta_swt1a,sta_swt2a,sta_swt21a,st_a,stb_swt1a_2b,stb_swt1b,st_b sta_swt1a,stb_swt1b 8,8 NULL 233 Using intersect(sta_swt1a,stb_swt1b); Using where
explain select st_a from t1
where st_a=1 and swt1a=1 and st_b=1 and swt1b=1 and swt1b=1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index_merge sta_swt12a,sta_swt1a,sta_swt2a,sta_swt21a,st_a,stb_swt1a_2b,stb_swt1b,st_b sta_swt1a,stb_swt1b 8,8 NULL 233 Using intersect(sta_swt1a,stb_swt1b); Using where; Using index
explain select st_a from t1
where st_a=1 and swt1a=1 and st_b=1 and swt1b=1 and swt1b=1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index_merge sta_swt12a,sta_swt1a,sta_swt2a,sta_swt21a,st_a,stb_swt1a_2b,stb_swt1b,st_b sta_swt1a,stb_swt1b 8,8 NULL 233 Using intersect(sta_swt1a,stb_swt1b); Using where; Using index
drop table t0,t1;
create table t2 (
a char(10),
b char(10),
filler1 char(255),
filler2 char(255),
key(a(5)),
key(b(5))
);
select count(a) from t2 where a='BBBBBBBB';
count(a)
4
select count(a) from t2 where b='BBBBBBBB';
count(a)
4
expla_or_bin select count(a_or_b) from t2 where a_or_b='AAAAAAAA' a_or_bnd a_or_b='AAAAAAAA';
id select_type ta_or_ba_or_ble type possia_or_ble_keys key key_len ref rows Extra_or_b
1 SIMPLE t2 ref a_or_b,a_or_b a_or_b 23 const 4 Using where
select count(a) from t2 where a='AAAAAAAA' and b='AAAAAAAA';
count(a)
4
select count(a) from t2 ignore index(a,b) where a='AAAAAAAA' and b='AAAAAAAA';
count(a)
4
insert into t2 values ('ab', 'ab', 'uh', 'oh');
explain select a from t2 where a='ab';
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t2 ref a a 23 const 1 Using where
drop table t2;
CREATE TABLE t1(c1 INT, c2 INT DEFAULT 0, c3 CHAR(255) DEFAULT '',
KEY(c1), KEY(c2), KEY(c3));
INSERT INTO t1(c1) VALUES(0),(0),(0),(0),(0),(0),(0),(0),(0),(0),(0),(0),(0),
(0),(0),(0),(0),(0),(0),(0),(0),(0),(0),(0),(0),(0),(0),(0),(0);
INSERT INTO t1 VALUES(0,0,0);
CREATE TABLE t2(c1 int);
INSERT INTO t2 VALUES(1);
DELETE t1 FROM t1,t2 WHERE t1.c1=0 AND t1.c2=0;
SELECT * FROM t1;
c1 c2 c3
DROP TABLE t1,t2;
#---------------- Index merge test 2 -------------------------------------------
SET SESSION STORAGE_ENGINE = MyISAM;
drop table if exists t1,t2;
create table t1
(
key1 int not null,
key2 int not null,
INDEX i1(key1),
INDEX i2(key2)
);
explain select * from t1 where key1 < 5 or key2 > 197;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index_merge i1,i2 i1,i2 4,4 NULL 10 Using sort_union(i1,i2); Using where
select * from t1 where key1 < 5 or key2 > 197;
key1 key2
0 200
1 199
2 198
3 197
4 196
explain select * from t1 where key1 < 3 or key2 > 195;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index_merge i1,i2 i1,i2 4,4 NULL 10 Using sort_union(i1,i2); Using where
select * from t1 where key1 < 3 or key2 > 195;
key1 key2
0 200
1 199
2 198
3 197
4 196
alter table t1 add str1 char (100) not null,
add zeroval int not null default 0,
add str2 char (100) not null,
add str3 char (100) not null;
update t1 set str1='aaa', str2='bbb', str3=concat(key2, '-', key1 div 2, '_' ,if(key1 mod 2 = 0, 'a', 'A'));
alter table t1 add primary key (str1, zeroval, str2, str3);
explain select * from t1 where key1 < 5 or key2 > 197;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index_merge i1,i2 i1,i2 4,4 NULL 10 Using sort_union(i1,i2); Using where
select * from t1 where key1 < 5 or key2 > 197;
key1 key2 str1 zeroval str2 str3
0 200 aaa 0 bbb 200-0_a
1 199 aaa 0 bbb 199-0_A
2 198 aaa 0 bbb 198-1_a
3 197 aaa 0 bbb 197-1_A
4 196 aaa 0 bbb 196-2_a
explain select * from t1 where key1 < 3 or key2 > 195;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index_merge i1,i2 i1,i2 4,4 NULL 10 Using sort_union(i1,i2); Using where
select * from t1 where key1 < 3 or key2 > 195;
key1 key2 str1 zeroval str2 str3
0 200 aaa 0 bbb 200-0_a
1 199 aaa 0 bbb 199-0_A
2 198 aaa 0 bbb 198-1_a
3 197 aaa 0 bbb 197-1_A
4 196 aaa 0 bbb 196-2_a
drop table t1;
create table t1 (
pk integer not null auto_increment primary key,
key1 integer,
key2 integer not null,
filler char (200),
index (key1),
index (key2)
);
show warnings;
Level Code Message
explain select pk from t1 where key1 = 1 and key2 = 1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref key1,key2 key1 5 const 4 Using where
select pk from t1 where key2 = 1 and key1 = 1;
pk
26
27
select pk from t1 ignore index(key1,key2) where key2 = 1 and key1 = 1;
pk
26
27
drop table t1;
create table t1 (
pk int primary key auto_increment,
key1a int,
key2a int,
key1b int,
key2b int,
dummy1 int,
dummy2 int,
dummy3 int,
dummy4 int,
key3a int,
key3b int,
filler1 char (200),
index i1(key1a, key1b),
index i2(key2a, key2b),
index i3(key3a, key3b)
) ENGINE=myisam;
create table t2 (a int);
insert into t2 values (0),(1),(2),(3),(4),(NULL);
insert into t1 (key1a, key1b, key2a, key2b, key3a, key3b)
select A.a, B.a, C.a, D.a, C.a, D.a from t2 A,t2 B,t2 C, t2 D;
insert into t1 (key1a, key1b, key2a, key2b, key3a, key3b)
select key1a, key1b, key2a, key2b, key3a, key3b from t1;
insert into t1 (key1a, key1b, key2a, key2b, key3a, key3b)
select key1a, key1b, key2a, key2b, key3a, key3b from t1;
analyze table t1;
Table Op Msg_type Msg_text
test.t1 analyze status OK
select count(*) from t1;
count(*)
5184
explain select count(*) from t1 where
key1a = 2 and key1b is null and key2a = 2 and key2b is null;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index_merge i1,i2 i1,i2 10,10 NULL 2 Using intersect(i1,i2); Using where; Using index
select count(*) from t1 where
key1a = 2 and key1b is null and key2a = 2 and key2b is null;
count(*)
4
explain select count(*) from t1 where
key1a = 2 and key1b is null and key3a = 2 and key3b is null;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index_merge i1,i3 i1,i3 10,10 NULL 2 Using intersect(i1,i3); Using where; Using index
select count(*) from t1 where
key1a = 2 and key1b is null and key3a = 2 and key3b is null;
count(*)
4
drop table t1,t2;
create table t1 (
id1 int,
id2 date ,
index idx2 (id1,id2),
index idx1 (id2)
);
insert into t1 values(1,'20040101'), (2,'20040102');
select * from t1 where id1 = 1 and id2= '20040101';
id1 id2
1 2004-01-01
drop table t1;
create table t1
(
key1 int not null,
key2 int not null default 0,
key3 int not null default 0
);
insert into t1(key1) values (1),(2),(3),(4),(5),(6),(7),(8);
set @d=8;
begin;
insert into t1 (key1) select key1+@d from t1;
set @d=@d*2;
insert into t1 (key1) select key1+@d from t1;
set @d=@d*2;
insert into t1 (key1) select key1+@d from t1;
set @d=@d*2;
insert into t1 (key1) select key1+@d from t1;
set @d=@d*2;
insert into t1 (key1) select key1+@d from t1;
set @d=@d*2;
insert into t1 (key1) select key1+@d from t1;
set @d=@d*2;
insert into t1 (key1) select key1+@d from t1;
set @d=@d*2;
commit;
alter table t1 add index i2(key2);
alter table t1 add index i3(key3);
update t1 set key2=key1,key3=key1;
explain select * from t1 where (key3 > 30 and key3<35) or (key2 >32 and key2 < 40);
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index_merge i2,i3 i3,i2 4,4 NULL 11 Using sort_union(i3,i2); Using where
select * from t1 where (key3 > 30 and key3<35) or (key2 >32 and key2 < 40);
key1 key2 key3
31 31 31
32 32 32
33 33 33
34 34 34
35 35 35
36 36 36
37 37 37
38 38 38
39 39 39
drop table t1;
#---------------- 2-sweeps read Index merge test 2 -------------------------------
SET SESSION STORAGE_ENGINE = MyISAM;
drop table if exists t1;
create table t1 (
pk int primary key,
key1 int,
key2 int,
filler char(200),
filler2 char(200),
index(key1),
index(key2)
);
select * from t1 where (key1 >= 2 and key1 <= 10) or (pk >= 4 and pk <=8 );
pk key1 key2 filler filler2
10 10 10 filler-data filler-data-2
9 9 9 filler-data filler-data-2
8 8 8 filler-data filler-data-2
7 7 7 filler-data filler-data-2
6 6 6 filler-data filler-data-2
5 5 5 filler-data filler-data-2
4 4 4 filler-data filler-data-2
3 3 3 filler-data filler-data-2
2 2 2 filler-data filler-data-2
set @maxv=1000;
select * from t1 where
(pk < 5) or (pk > 10 and pk < 15) or (pk >= 50 and pk < 55 ) or (pk > @maxv-10)
or key1=18 or key1=60;
pk key1 key2 filler filler2
1000 1000 1000 filler-data filler-data-2
999 999 999 filler-data filler-data-2
998 998 998 filler-data filler-data-2
997 997 997 filler-data filler-data-2
996 996 996 filler-data filler-data-2
995 995 995 filler-data filler-data-2
994 994 994 filler-data filler-data-2
993 993 993 filler-data filler-data-2
992 992 992 filler-data filler-data-2
991 991 991 filler-data filler-data-2
60 60 60 filler-data filler-data-2
54 54 54 filler-data filler-data-2
53 53 53 filler-data filler-data-2
52 52 52 filler-data filler-data-2
51 51 51 filler-data filler-data-2
50 50 50 filler-data filler-data-2
18 18 18 filler-data filler-data-2
14 14 14 filler-data filler-data-2
13 13 13 filler-data filler-data-2
12 12 12 filler-data filler-data-2
11 11 11 filler-data filler-data-2
4 4 4 filler-data filler-data-2
3 3 3 filler-data filler-data-2
2 2 2 filler-data filler-data-2
1 1 1 filler-data filler-data-2
select * from t1 where
(pk < 5) or (pk > 10 and pk < 15) or (pk >= 50 and pk < 55 ) or (pk > @maxv-10)
or key1 < 3 or key1 > @maxv-11;
pk key1 key2 filler filler2
1000 1000 1000 filler-data filler-data-2
999 999 999 filler-data filler-data-2
998 998 998 filler-data filler-data-2
997 997 997 filler-data filler-data-2
996 996 996 filler-data filler-data-2
995 995 995 filler-data filler-data-2
994 994 994 filler-data filler-data-2
993 993 993 filler-data filler-data-2
992 992 992 filler-data filler-data-2
991 991 991 filler-data filler-data-2
990 990 990 filler-data filler-data-2
54 54 54 filler-data filler-data-2
53 53 53 filler-data filler-data-2
52 52 52 filler-data filler-data-2
51 51 51 filler-data filler-data-2
50 50 50 filler-data filler-data-2
14 14 14 filler-data filler-data-2
13 13 13 filler-data filler-data-2
12 12 12 filler-data filler-data-2
11 11 11 filler-data filler-data-2
4 4 4 filler-data filler-data-2
3 3 3 filler-data filler-data-2
2 2 2 filler-data filler-data-2
1 1 1 filler-data filler-data-2
select * from t1 where
(pk < 5) or (pk > 10 and pk < 15) or (pk >= 50 and pk < 55 ) or (pk > @maxv-10)
or
(key1 < 5) or (key1 > 10 and key1 < 15) or (key1 >= 50 and key1 < 55 ) or (key1 > @maxv-10);
pk key1 key2 filler filler2
1000 1000 1000 filler-data filler-data-2
999 999 999 filler-data filler-data-2
998 998 998 filler-data filler-data-2
997 997 997 filler-data filler-data-2
996 996 996 filler-data filler-data-2
995 995 995 filler-data filler-data-2
994 994 994 filler-data filler-data-2
993 993 993 filler-data filler-data-2
992 992 992 filler-data filler-data-2
991 991 991 filler-data filler-data-2
54 54 54 filler-data filler-data-2
53 53 53 filler-data filler-data-2
52 52 52 filler-data filler-data-2
51 51 51 filler-data filler-data-2
50 50 50 filler-data filler-data-2
14 14 14 filler-data filler-data-2
13 13 13 filler-data filler-data-2
12 12 12 filler-data filler-data-2
11 11 11 filler-data filler-data-2
4 4 4 filler-data filler-data-2
3 3 3 filler-data filler-data-2
2 2 2 filler-data filler-data-2
1 1 1 filler-data filler-data-2
select * from t1 where
(pk > 10 and pk < 15) or (pk >= 50 and pk < 55 )
or
(key1 < 5) or (key1 > @maxv-10);
pk key1 key2 filler filler2
1000 1000 1000 filler-data filler-data-2
999 999 999 filler-data filler-data-2
998 998 998 filler-data filler-data-2
997 997 997 filler-data filler-data-2
996 996 996 filler-data filler-data-2
995 995 995 filler-data filler-data-2
994 994 994 filler-data filler-data-2
993 993 993 filler-data filler-data-2
992 992 992 filler-data filler-data-2
991 991 991 filler-data filler-data-2
54 54 54 filler-data filler-data-2
53 53 53 filler-data filler-data-2
52 52 52 filler-data filler-data-2
51 51 51 filler-data filler-data-2
50 50 50 filler-data filler-data-2
14 14 14 filler-data filler-data-2
13 13 13 filler-data filler-data-2
12 12 12 filler-data filler-data-2
11 11 11 filler-data filler-data-2
4 4 4 filler-data filler-data-2
3 3 3 filler-data filler-data-2
2 2 2 filler-data filler-data-2
1 1 1 filler-data filler-data-2
drop table t1;
#---------------- Clustered PK ROR-index_merge tests -----------------------------
SET SESSION STORAGE_ENGINE = MyISAM;
drop table if exists t1;
create table t1
(
pk1 int not null,
pk2 int not null,
key1 int not null,
key2 int not null,
pktail1ok int not null,
pktail2ok int not null,
pktail3bad int not null,
pktail4bad int not null,
pktail5bad int not null,
pk2copy int not null,
badkey int not null,
filler1 char (200),
filler2 char (200),
key (key1),
key (key2),
/* keys with tails from CPK members */
key (pktail1ok, pk1),
key (pktail2ok, pk1, pk2),
key (pktail3bad, pk2, pk1),
key (pktail4bad, pk1, pk2copy),
key (pktail5bad, pk1, pk2, pk2copy),
primary key (pk1, pk2)
);
explain select * from t1 where pk1 = 1 and pk2 < 80 and key1=0;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range PRIMARY,key1 PRIMARY 8 NULL 9 Using where; Using MRR
select * from t1 where pk1 = 1 and pk2 < 80 and key1=0;
pk1 pk2 key1 key2 pktail1ok pktail2ok pktail3bad pktail4bad pktail5bad pk2copy badkey filler1 filler2
1 19 0 0 0 0 0 0 0 19 0 filler-data-19 filler2
1 18 0 0 0 0 0 0 0 18 0 filler-data-18 filler2
1 17 0 0 0 0 0 0 0 17 0 filler-data-17 filler2
1 16 0 0 0 0 0 0 0 16 0 filler-data-16 filler2
1 15 0 0 0 0 0 0 0 15 0 filler-data-15 filler2
1 14 0 0 0 0 0 0 0 14 0 filler-data-14 filler2
1 13 0 0 0 0 0 0 0 13 0 filler-data-13 filler2
1 12 0 0 0 0 0 0 0 12 0 filler-data-12 filler2
1 11 0 0 0 0 0 0 0 11 0 filler-data-11 filler2
1 10 0 0 0 0 0 0 0 10 0 filler-data-10 filler2
explain select pk1,pk2 from t1 where key1 = 10 and key2=10 and 2*pk1+1 < 2*96+1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index_merge key1,key2 key1,key2 4,4 NULL 1 Using intersect(key1,key2); Using where
select pk1,pk2 from t1 where key1 = 10 and key2=10 and 2*pk1+1 < 2*96+1;
pk1 pk2
95 59
95 58
95 57
95 56
95 55
95 54
95 53
95 52
95 51
95 50
explain select * from t1 where badkey=1 and key1=10;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref key1 key1 4 const 83 Using where
explain select * from t1 where pk1 < 7500 and key1 = 10;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref PRIMARY,key1 key1 4 const ROWS Using where
explain select * from t1 where pktail1ok=1 and key1=10;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref key1,pktail1ok key1 4 const 83 Using where
explain select * from t1 where pktail2ok=1 and key1=10;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref key1,pktail2ok pktail2ok 4 const 78 Using where
explain select * from t1 where (pktail2ok=1 and pk1< 50000) or key1=10;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index_merge PRIMARY,key1,pktail2ok pktail2ok,key1 8,4 NULL 161 Using sort_union(pktail2ok,key1); Using where
explain select * from t1 where pktail3bad=1 and key1=10;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref key1,pktail3bad pktail3bad 4 const 69 Using where
explain select * from t1 where pktail4bad=1 and key1=10;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref key1,pktail4bad pktail4bad 4 const 78 Using where
explain select * from t1 where pktail5bad=1 and key1=10;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref key1,pktail5bad pktail5bad 4 const 67 Using where
explain select pk1,pk2,key1,key2 from t1 where key1 = 10 and key2=10 limit 10;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index_merge key1,key2 key1,key2 4,4 NULL 1 Using intersect(key1,key2); Using where
select pk1,pk2,key1,key2 from t1 where key1 = 10 and key2=10 limit 10;
pk1 pk2 key1 key2
104 49 10 10
104 48 10 10
104 47 10 10
104 46 10 10
104 45 10 10
104 44 10 10
104 43 10 10
104 42 10 10
104 41 10 10
104 40 10 10
drop table t1;
create table t1
(
RUNID varchar(22),
SUBMITNR varchar(5),
ORDERNR char(1),
PROGRAMM varchar(8),
TESTID varchar(4),
UCCHECK char(1),
ETEXT varchar(80),
ETEXT_TYPE char(1),
INFO char(1),
SEVERITY int,
TADIRFLAG char(1),
PRIMARY KEY (RUNID,SUBMITNR,ORDERNR,PROGRAMM,TESTID,UCCHECK),
KEY `TVERM~KEY` (PROGRAMM,TESTID,UCCHECK)
);
update t1 set `ETEXT` = '', `ETEXT_TYPE`='', `INFO`='', `SEVERITY`='', `TADIRFLAG`=''
WHERE
`RUNID`= '' AND `SUBMITNR`= '' AND `ORDERNR`='' AND `PROGRAMM`='' AND
`TESTID`='' AND `UCCHECK`='';
drop table t1;
|