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drop table if exists t1,t2,t3,t4;
create table t1 (
c_id int(11) not null default '0',
org_id int(11) default null,
unique key contacts$c_id (c_id),
key contacts$org_id (org_id)
) engine=innodb;
insert into t1 values
(2,null),(120,null),(141,null),(218,7), (128,1),
(151,2),(234,2),(236,2),(243,2),(255,2),(259,2),(232,3),(235,3),(238,3),
(246,3),(253,3),(269,3),(285,3),(291,3),(293,3),(131,4),(230,4),(231,4);
create table t2 (
slai_id int(11) not null default '0',
owner_tbl int(11) default null,
owner_id int(11) default null,
sla_id int(11) default null,
inc_web int(11) default null,
inc_email int(11) default null,
inc_chat int(11) default null,
inc_csr int(11) default null,
inc_total int(11) default null,
time_billed int(11) default null,
activedate timestamp null default null,
expiredate timestamp null default null,
state int(11) default null,
sla_set int(11) default null,
unique key t2$slai_id (slai_id),
key t2$owner_id (owner_id),
key t2$sla_id (sla_id)
) engine=innodb;
insert into t2(slai_id, owner_tbl, owner_id, sla_id) values
(1,3,1,1), (3,3,10,2), (4,3,3,6), (5,3,2,5), (6,3,8,3), (7,3,9,7),
(8,3,6,8), (9,3,4,9), (10,3,5,10), (11,3,11,11), (12,3,7,12);
flush tables;
select si.slai_id
from t1 c join t2 si on
((si.owner_tbl = 3 and si.owner_id = c.org_id) or
( si.owner_tbl = 2 and si.owner_id = c.c_id))
where
c.c_id = 218 and expiredate is null;
slai_id
12
select * from t1 where org_id is null;
c_id org_id
2 NULL
120 NULL
141 NULL
select si.slai_id
from t1 c join t2 si on
((si.owner_tbl = 3 and si.owner_id = c.org_id) or
( si.owner_tbl = 2 and si.owner_id = c.c_id))
where
c.c_id = 218 and expiredate is null;
slai_id
12
drop table t1, t2;
CREATE TABLE t1 (a int, b int, KEY b (b)) Engine=InnoDB;
CREATE TABLE t2 (a int, b int, PRIMARY KEY (a,b)) Engine=InnoDB;
CREATE TABLE t3 (a int, b int, c int, PRIMARY KEY (a),
UNIQUE KEY b (b,c), KEY a (a,b,c)) Engine=InnoDB;
INSERT INTO t1 VALUES (1, 1);
INSERT INTO t1 SELECT a + 1, b + 1 FROM t1;
INSERT INTO t1 SELECT a + 2, b + 2 FROM t1;
INSERT INTO t2 VALUES (1,1),(1,2),(1,3),(1,4),(1,5),(1,6),(1,7),(1,8);
INSERT INTO t2 SELECT a + 1, b FROM t2;
DELETE FROM t2 WHERE a = 1 AND b < 2;
INSERT INTO t3 VALUES (1,1,1),(2,1,2);
INSERT INTO t3 SELECT a + 2, a + 2, 3 FROM t3;
INSERT INTO t3 SELECT a + 4, a + 4, 3 FROM t3;
SELECT STRAIGHT_JOIN SQL_NO_CACHE t1.b, t1.a FROM t1, t3, t2 WHERE
t3.a = t2.a AND t2.b = t1.a AND t3.b = 1 AND t3.c IN (1, 2)
ORDER BY t1.b LIMIT 2;
b a
1 1
2 2
SELECT STRAIGHT_JOIN SQL_NO_CACHE t1.b, t1.a FROM t1, t3, t2 WHERE
t3.a = t2.a AND t2.b = t1.a AND t3.b = 1 AND t3.c IN (1, 2)
ORDER BY t1.b LIMIT 5;
b a
1 1
2 2
2 2
3 3
3 3
DROP TABLE t1, t2, t3;
CREATE TABLE `t1` (`id1` INT) ;
INSERT INTO `t1` (`id1`) VALUES (1),(5),(2);
CREATE TABLE `t2` (
`id1` INT,
`id2` INT NOT NULL,
`id3` INT,
`id4` INT NOT NULL,
UNIQUE (`id2`,`id4`),
KEY (`id1`)
) ENGINE=InnoDB;
INSERT INTO `t2`(`id1`,`id2`,`id3`,`id4`) VALUES
(1,1,1,0),
(1,1,2,1),
(5,1,2,2),
(6,1,2,3),
(1,2,2,2),
(1,2,1,1);
SELECT `id1` FROM `t1` WHERE `id1` NOT IN (SELECT `id1` FROM `t2` WHERE `id2` = 1 AND `id3` = 2);
id1
2
DROP TABLE t1, t2;
create table t1 (c1 int) engine=innodb;
handler t1 open;
handler t1 read first;
c1
Before and after comparison
0
drop table t1;
CREATE TABLE t1(c1 TEXT, UNIQUE (c1(1)), cnt INT DEFAULT 1)
ENGINE=INNODB CHARACTER SET UTF8;
INSERT INTO t1 (c1) VALUES ('1a');
SELECT * FROM t1;
c1 cnt
1a 1
INSERT INTO t1 (c1) VALUES ('1b') ON DUPLICATE KEY UPDATE cnt=cnt+1;
SELECT * FROM t1;
c1 cnt
1a 2
DROP TABLE t1;
CREATE TABLE t1(c1 VARCHAR(2), UNIQUE (c1(1)), cnt INT DEFAULT 1)
ENGINE=INNODB CHARACTER SET UTF8;
INSERT INTO t1 (c1) VALUES ('1a');
SELECT * FROM t1;
c1 cnt
1a 1
INSERT INTO t1 (c1) VALUES ('1b') ON DUPLICATE KEY UPDATE cnt=cnt+1;
SELECT * FROM t1;
c1 cnt
1a 2
DROP TABLE t1;
CREATE TABLE t1(c1 CHAR(2), UNIQUE (c1(1)), cnt INT DEFAULT 1)
ENGINE=INNODB CHARACTER SET UTF8;
INSERT INTO t1 (c1) VALUES ('1a');
SELECT * FROM t1;
c1 cnt
1a 1
INSERT INTO t1 (c1) VALUES ('1b') ON DUPLICATE KEY UPDATE cnt=cnt+1;
SELECT * FROM t1;
c1 cnt
1a 2
DROP TABLE t1;
CREATE TABLE t1 (
a1 decimal(10,0) DEFAULT NULL,
a2 blob,
a3 time DEFAULT NULL,
a4 blob,
a5 char(175) DEFAULT NULL,
a6 timestamp NOT NULL DEFAULT '0000-00-00 00:00:00',
a7 tinyblob,
INDEX idx (a6,a7(239),a5)
) ENGINE=InnoDB;
EXPLAIN SELECT a4 FROM t1 WHERE
a6=NULL AND
a4='UNcT5pIde4I6c2SheTo4gt92OV1jgJCVkXmzyf325R1DwLURkbYHwhydANIZMbKTgdcR5xS';
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE NULL NULL NULL NULL NULL NULL NULL Impossible WHERE noticed after reading const tables
EXPLAIN SELECT t1.a4 FROM t1, t1 t WHERE
t.a6=t.a6 AND t1.a6=NULL AND
t1.a4='UNcT5pIde4I6c2SheTo4gt92OV1jgJCVkXmzyf325R1DwLURkbYHwhydANIZMbKTgdcR5xS';
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE NULL NULL NULL NULL NULL NULL NULL Impossible WHERE noticed after reading const tables
DROP TABLE t1;
End of 4.1 tests
create table t1m (a int) engine=myisam;
create table t1i (a int) engine=innodb;
create table t2m (a int) engine=myisam;
create table t2i (a int) engine=innodb;
insert into t2m values (5);
insert into t2i values (5);
select min(a) from t1m;
min(a)
NULL
select min(7) from t1m;
min(7)
NULL
select min(7) from DUAL;
min(7)
7
explain select min(7) from t2m join t1m;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE NULL NULL NULL NULL NULL NULL NULL Select tables optimized away
select min(7) from t2m join t1m;
min(7)
NULL
select max(a) from t1m;
max(a)
NULL
select max(7) from t1m;
max(7)
NULL
select max(7) from DUAL;
max(7)
7
explain select max(7) from t2m join t1m;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE NULL NULL NULL NULL NULL NULL NULL Select tables optimized away
select max(7) from t2m join t1m;
max(7)
NULL
select 1, min(a) from t1m where a=99;
1 min(a)
1 NULL
select 1, min(a) from t1m where 1=99;
1 min(a)
1 NULL
select 1, min(1) from t1m where a=99;
1 min(1)
1 NULL
select 1, min(1) from t1m where 1=99;
1 min(1)
1 NULL
select 1, max(a) from t1m where a=99;
1 max(a)
1 NULL
select 1, max(a) from t1m where 1=99;
1 max(a)
1 NULL
select 1, max(1) from t1m where a=99;
1 max(1)
1 NULL
select 1, max(1) from t1m where 1=99;
1 max(1)
1 NULL
select min(a) from t1i;
min(a)
NULL
select min(7) from t1i;
min(7)
NULL
select min(7) from DUAL;
min(7)
7
explain select min(7) from t2i join t1i;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t2i ALL NULL NULL NULL NULL 1
1 SIMPLE t1i ALL NULL NULL NULL NULL 1
select min(7) from t2i join t1i;
min(7)
NULL
select max(a) from t1i;
max(a)
NULL
select max(7) from t1i;
max(7)
NULL
select max(7) from DUAL;
max(7)
7
explain select max(7) from t2i join t1i;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t2i ALL NULL NULL NULL NULL 1
1 SIMPLE t1i ALL NULL NULL NULL NULL 1
select max(7) from t2i join t1i;
max(7)
NULL
select 1, min(a) from t1i where a=99;
1 min(a)
1 NULL
select 1, min(a) from t1i where 1=99;
1 min(a)
1 NULL
select 1, min(1) from t1i where a=99;
1 min(1)
1 NULL
select 1, min(1) from t1i where 1=99;
1 min(1)
1 NULL
select 1, max(a) from t1i where a=99;
1 max(a)
1 NULL
select 1, max(a) from t1i where 1=99;
1 max(a)
1 NULL
select 1, max(1) from t1i where a=99;
1 max(1)
1 NULL
select 1, max(1) from t1i where 1=99;
1 max(1)
1 NULL
explain select count(*), min(7), max(7) from t1m, t1i;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1m system NULL NULL NULL NULL 0 const row not found
1 SIMPLE t1i ALL NULL NULL NULL NULL 1
select count(*), min(7), max(7) from t1m, t1i;
count(*) min(7) max(7)
0 NULL NULL
explain select count(*), min(7), max(7) from t1m, t2i;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1m system NULL NULL NULL NULL 0 const row not found
1 SIMPLE t2i ALL NULL NULL NULL NULL 1
select count(*), min(7), max(7) from t1m, t2i;
count(*) min(7) max(7)
0 NULL NULL
explain select count(*), min(7), max(7) from t2m, t1i;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t2m system NULL NULL NULL NULL 1
1 SIMPLE t1i ALL NULL NULL NULL NULL 1
select count(*), min(7), max(7) from t2m, t1i;
count(*) min(7) max(7)
0 NULL NULL
drop table t1m, t1i, t2m, t2i;
create table t1 (
a1 char(64), a2 char(64), b char(16), c char(16) not null, d char(16), dummy char(64) default ' '
);
insert into t1 (a1, a2, b, c, d) values
('a','a','a','a111','xy1'),('a','a','a','b111','xy2'),('a','a','a','c111','xy3'),('a','a','a','d111','xy4'),
('a','a','b','e112','xy1'),('a','a','b','f112','xy2'),('a','a','b','g112','xy3'),('a','a','b','h112','xy4'),
('a','b','a','i121','xy1'),('a','b','a','j121','xy2'),('a','b','a','k121','xy3'),('a','b','a','l121','xy4'),
('a','b','b','m122','xy1'),('a','b','b','n122','xy2'),('a','b','b','o122','xy3'),('a','b','b','p122','xy4'),
('b','a','a','a211','xy1'),('b','a','a','b211','xy2'),('b','a','a','c211','xy3'),('b','a','a','d211','xy4'),
('b','a','b','e212','xy1'),('b','a','b','f212','xy2'),('b','a','b','g212','xy3'),('b','a','b','h212','xy4'),
('b','b','a','i221','xy1'),('b','b','a','j221','xy2'),('b','b','a','k221','xy3'),('b','b','a','l221','xy4'),
('b','b','b','m222','xy1'),('b','b','b','n222','xy2'),('b','b','b','o222','xy3'),('b','b','b','p222','xy4'),
('c','a','a','a311','xy1'),('c','a','a','b311','xy2'),('c','a','a','c311','xy3'),('c','a','a','d311','xy4'),
('c','a','b','e312','xy1'),('c','a','b','f312','xy2'),('c','a','b','g312','xy3'),('c','a','b','h312','xy4'),
('c','b','a','i321','xy1'),('c','b','a','j321','xy2'),('c','b','a','k321','xy3'),('c','b','a','l321','xy4'),
('c','b','b','m322','xy1'),('c','b','b','n322','xy2'),('c','b','b','o322','xy3'),('c','b','b','p322','xy4'),
('d','a','a','a411','xy1'),('d','a','a','b411','xy2'),('d','a','a','c411','xy3'),('d','a','a','d411','xy4'),
('d','a','b','e412','xy1'),('d','a','b','f412','xy2'),('d','a','b','g412','xy3'),('d','a','b','h412','xy4'),
('d','b','a','i421','xy1'),('d','b','a','j421','xy2'),('d','b','a','k421','xy3'),('d','b','a','l421','xy4'),
('d','b','b','m422','xy1'),('d','b','b','n422','xy2'),('d','b','b','o422','xy3'),('d','b','b','p422','xy4'),
('a','a','a','a111','xy1'),('a','a','a','b111','xy2'),('a','a','a','c111','xy3'),('a','a','a','d111','xy4'),
('a','a','b','e112','xy1'),('a','a','b','f112','xy2'),('a','a','b','g112','xy3'),('a','a','b','h112','xy4'),
('a','b','a','i121','xy1'),('a','b','a','j121','xy2'),('a','b','a','k121','xy3'),('a','b','a','l121','xy4'),
('a','b','b','m122','xy1'),('a','b','b','n122','xy2'),('a','b','b','o122','xy3'),('a','b','b','p122','xy4'),
('b','a','a','a211','xy1'),('b','a','a','b211','xy2'),('b','a','a','c211','xy3'),('b','a','a','d211','xy4'),
('b','a','b','e212','xy1'),('b','a','b','f212','xy2'),('b','a','b','g212','xy3'),('b','a','b','h212','xy4'),
('b','b','a','i221','xy1'),('b','b','a','j221','xy2'),('b','b','a','k221','xy3'),('b','b','a','l221','xy4'),
('b','b','b','m222','xy1'),('b','b','b','n222','xy2'),('b','b','b','o222','xy3'),('b','b','b','p222','xy4'),
('c','a','a','a311','xy1'),('c','a','a','b311','xy2'),('c','a','a','c311','xy3'),('c','a','a','d311','xy4'),
('c','a','b','e312','xy1'),('c','a','b','f312','xy2'),('c','a','b','g312','xy3'),('c','a','b','h312','xy4'),
('c','b','a','i321','xy1'),('c','b','a','j321','xy2'),('c','b','a','k321','xy3'),('c','b','a','l321','xy4'),
('c','b','b','m322','xy1'),('c','b','b','n322','xy2'),('c','b','b','o322','xy3'),('c','b','b','p322','xy4'),
('d','a','a','a411','xy1'),('d','a','a','b411','xy2'),('d','a','a','c411','xy3'),('d','a','a','d411','xy4'),
('d','a','b','e412','xy1'),('d','a','b','f412','xy2'),('d','a','b','g412','xy3'),('d','a','b','h412','xy4'),
('d','b','a','i421','xy1'),('d','b','a','j421','xy2'),('d','b','a','k421','xy3'),('d','b','a','l421','xy4'),
('d','b','b','m422','xy1'),('d','b','b','n422','xy2'),('d','b','b','o422','xy3'),('d','b','b','p422','xy4');
create table t4 (
pk_col int auto_increment primary key, a1 char(64), a2 char(64), b char(16), c char(16) not null, d char(16), dummy char(64) default ' '
) engine=innodb;
insert into t4 (a1, a2, b, c, d, dummy) select * from t1;
create index idx12672_0 on t4 (a1);
create index idx12672_1 on t4 (a1,a2,b,c);
create index idx12672_2 on t4 (a1,a2,b);
analyze table t1;
Table Op Msg_type Msg_text
test.t1 analyze status OK
select distinct a1 from t4 where pk_col not in (1,2,3,4);
a1
a
b
c
d
drop table t1,t4;
DROP TABLE IF EXISTS t2, t1;
CREATE TABLE t1 (i INT NOT NULL PRIMARY KEY) ENGINE= InnoDB;
CREATE TABLE t2 (
i INT NOT NULL,
FOREIGN KEY (i) REFERENCES t1 (i) ON DELETE NO ACTION
) ENGINE= InnoDB;
INSERT INTO t1 VALUES (1);
INSERT INTO t2 VALUES (1);
DELETE IGNORE FROM t1 WHERE i = 1;
Warnings:
Error 1451 Cannot delete or update a parent row: a foreign key constraint fails (`test/t2`, CONSTRAINT `t2_ibfk_1` FOREIGN KEY (`i`) REFERENCES `t1` (`i`) ON DELETE NO ACTION)
SELECT * FROM t1, t2;
i i
1 1
DROP TABLE t2, t1;
End of 4.1 tests.
create table t1 (
a varchar(30), b varchar(30), primary key(a), key(b)
) engine=innodb;
select distinct a from t1;
a
drop table t1;
create table t1(a int, key(a)) engine=innodb;
insert into t1 values(1);
select a, count(a) from t1 group by a with rollup;
a count(a)
1 1
NULL 1
drop table t1;
create table t1 (f1 int, f2 char(1), primary key(f1,f2)) engine=innodb;
insert into t1 values ( 1,"e"),(2,"a"),( 3,"c"),(4,"d");
alter table t1 drop primary key, add primary key (f2, f1);
explain select distinct f1 a, f1 b from t1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index NULL PRIMARY 5 NULL 4 Using index; Using temporary
explain select distinct f1, f2 from t1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range NULL PRIMARY 5 NULL 3 Using index for group-by; Using temporary
drop table t1;
CREATE TABLE t1 (id int(11) NOT NULL PRIMARY KEY, name varchar(20),
INDEX (name)) ENGINE=InnoDB;
CREATE TABLE t2 (id int(11) NOT NULL PRIMARY KEY, fkey int(11),
FOREIGN KEY (fkey) REFERENCES t2(id)) ENGINE=InnoDB;
INSERT INTO t1 VALUES (1,'A1'),(2,'A2'),(3,'B');
INSERT INTO t2 VALUES (1,1),(2,2),(3,2),(4,3),(5,3);
EXPLAIN
SELECT COUNT(*) FROM t2 LEFT JOIN t1 ON t2.fkey = t1.id
WHERE t1.name LIKE 'A%';
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index PRIMARY,name name 23 NULL 3 Using where; Using index
1 SIMPLE t2 ref fkey fkey 5 test.t1.id 1 Using where; Using index
EXPLAIN
SELECT COUNT(*) FROM t2 LEFT JOIN t1 ON t2.fkey = t1.id
WHERE t1.name LIKE 'A%' OR FALSE;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t2 index NULL fkey 5 NULL 5 Using index
1 SIMPLE t1 eq_ref PRIMARY PRIMARY 4 test.t2.fkey 1 Using where
DROP TABLE t1,t2;
create table t1(f1 varchar(800) binary not null, key(f1)) engine = innodb
character set utf8 collate utf8_general_ci;
Warnings:
Warning 1071 Specified key was too long; max key length is 767 bytes
insert into t1 values('aaa');
drop table t1;
CREATE TABLE t1 (a INT PRIMARY KEY, b INT, c FLOAT, KEY b(b)) ENGINE = INNODB;
INSERT INTO t1 VALUES ( 1 , 1 , 1);
INSERT INTO t1 SELECT a + 1 , MOD(a + 1 , 20), 1 FROM t1;
INSERT INTO t1 SELECT a + 2 , MOD(a + 2 , 20), 1 FROM t1;
INSERT INTO t1 SELECT a + 4 , MOD(a + 4 , 20), 1 FROM t1;
INSERT INTO t1 SELECT a + 8 , MOD(a + 8 , 20), 1 FROM t1;
INSERT INTO t1 SELECT a + 16, MOD(a + 16, 20), 1 FROM t1;
INSERT INTO t1 SELECT a + 32, MOD(a + 32, 20), 1 FROM t1;
INSERT INTO t1 SELECT a + 64, MOD(a + 64, 20), 1 FROM t1;
EXPLAIN SELECT b, SUM(c) FROM t1 GROUP BY b;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index NULL b 5 NULL 128
EXPLAIN SELECT SQL_BIG_RESULT b, SUM(c) FROM t1 GROUP BY b;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 128 Using filesort
DROP TABLE t1;
CREATE TABLE t1 (
id int NOT NULL,
name varchar(20) NOT NULL,
dept varchar(20) NOT NULL,
age tinyint(3) unsigned NOT NULL,
PRIMARY KEY (id),
INDEX (name,dept)
) ENGINE=InnoDB;
INSERT INTO t1(id, dept, age, name) VALUES
(3987, 'cs1', 10, 'rs1'), (3988, 'cs2', 20, 'rs1'), (3995, 'cs3', 10, 'rs2'),
(3996, 'cs4', 20, 'rs2'), (4003, 'cs5', 10, 'rs3'), (4004, 'cs6', 20, 'rs3'),
(4011, 'cs7', 10, 'rs4'), (4012, 'cs8', 20, 'rs4'), (4019, 'cs9', 10, 'rs5'),
(4020, 'cs10', 20, 'rs5'),(4027, 'cs11', 10, 'rs6'),(4028, 'cs12', 20, 'rs6');
EXPLAIN SELECT DISTINCT t1.name, t1.dept FROM t1 WHERE t1.name='rs5';
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range name name 44 NULL 2 Using where; Using index for group-by
SELECT DISTINCT t1.name, t1.dept FROM t1 WHERE t1.name='rs5';
name dept
rs5 cs10
rs5 cs9
DELETE FROM t1;
EXPLAIN SELECT DISTINCT t1.name, t1.dept FROM t1 WHERE t1.name='rs5';
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range name name 44 NULL 2 Using where; Using index for group-by
SELECT DISTINCT t1.name, t1.dept FROM t1 WHERE t1.name='rs5';
name dept
DROP TABLE t1;
show variables like 'innodb_rollback_on_timeout';
Variable_name Value
innodb_rollback_on_timeout OFF
create table t1 (a int unsigned not null primary key) engine = innodb;
insert into t1 values (1);
commit;
begin work;
insert into t1 values (2);
select * from t1;
a
1
2
begin work;
insert into t1 values (5);
select * from t1;
a
1
5
insert into t1 values (2);
ERROR HY000: Lock wait timeout exceeded; try restarting transaction
select * from t1;
a
1
5
commit;
select * from t1;
a
1
2
commit;
select * from t1;
a
1
2
5
drop table t1;
set @save_qcache_size=@@global.query_cache_size;
set @save_qcache_type=@@global.query_cache_type;
set global query_cache_size=10*1024*1024;
set global query_cache_type=1;
drop table if exists `test`;
Warnings:
Note 1051 Unknown table 'test'
CREATE TABLE `test` (`test1` varchar(3) NOT NULL,
`test2` varchar(4) NOT NULL,PRIMARY KEY (`test1`))
ENGINE=InnoDB DEFAULT CHARSET=latin1;
INSERT INTO `test` (`test1`, `test2`) VALUES ('tes', '5678');
select * from test;
test1 test2
tes 5678
INSERT INTO `test` (`test1`, `test2`) VALUES ('tes', '1234')
ON DUPLICATE KEY UPDATE `test2` = '1234';
select * from test;
test1 test2
tes 1234
flush tables;
select * from test;
test1 test2
tes 1234
drop table test;
set global query_cache_type=@save_qcache_type;
set global query_cache_size=@save_qcache_size;
create table t1(
id int auto_increment,
c char(1) not null,
counter int not null default 1,
primary key (id),
unique key (c)
) engine=innodb;
insert into t1 (id, c) values
(NULL, 'a'),
(NULL, 'a')
on duplicate key update id = values(id), counter = counter + 1;
select * from t1;
id c counter
2 a 2
insert into t1 (id, c) values
(NULL, 'b')
on duplicate key update id = values(id), counter = counter + 1;
select * from t1;
id c counter
2 a 2
3 b 1
truncate table t1;
insert into t1 (id, c) values (NULL, 'a');
select * from t1;
id c counter
1 a 1
insert into t1 (id, c) values (NULL, 'b'), (NULL, 'b')
on duplicate key update id = values(id), c = values(c), counter = counter + 1;
select * from t1;
id c counter
1 a 1
3 b 2
insert into t1 (id, c) values (NULL, 'a')
on duplicate key update id = values(id), c = values(c), counter = counter + 1;
select * from t1;
id c counter
3 b 2
4 a 2
drop table t1;
CREATE TABLE t1(
id int AUTO_INCREMENT PRIMARY KEY,
stat_id int NOT NULL,
acct_id int DEFAULT NULL,
INDEX idx1 (stat_id, acct_id),
INDEX idx2 (acct_id)
) ENGINE=MyISAM;
CREATE TABLE t2(
id int AUTO_INCREMENT PRIMARY KEY,
stat_id int NOT NULL,
acct_id int DEFAULT NULL,
INDEX idx1 (stat_id, acct_id),
INDEX idx2 (acct_id)
) ENGINE=InnoDB;
INSERT INTO t1(stat_id,acct_id) VALUES
(1,759), (2,831), (3,785), (4,854), (1,921),
(1,553), (2,589), (3,743), (2,827), (2,545),
(4,779), (4,783), (1,597), (1,785), (4,832),
(1,741), (1,833), (3,788), (2,973), (1,907);
INSERT INTO t1(stat_id,acct_id) SELECT stat_id, mod(id+100000, acct_id) FROM t1;
INSERT INTO t1(stat_id,acct_id) SELECT stat_id, mod(id+100000, acct_id) FROM t1;
INSERT INTO t1(stat_id,acct_id) SELECT stat_id, mod(id+100000, acct_id) FROM t1;
INSERT INTO t1(stat_id,acct_id) SELECT stat_id, mod(id+100000, acct_id) FROM t1;
INSERT INTO t1(stat_id,acct_id) SELECT stat_id, mod(id+100000, acct_id) FROM t1;
INSERT INTO t1(stat_id,acct_id) SELECT stat_id, mod(id+100000, acct_id) FROM t1;
INSERT INTO t1(stat_id,acct_id) SELECT stat_id, mod(id+100000, acct_id) FROM t1;
INSERT INTO t1(stat_id,acct_id) SELECT stat_id, mod(id+100000, acct_id) FROM t1;
INSERT INTO t1(stat_id,acct_id) SELECT stat_id, mod(id+100000, acct_id) FROM t1;
INSERT INTO t1(stat_id,acct_id) SELECT stat_id, mod(id+100000, acct_id) FROM t1;
INSERT INTO t1(stat_id,acct_id) SELECT stat_id, mod(id+100000, acct_id) FROM t1;
UPDATE t1 SET acct_id=785
WHERE MOD(stat_id,2)=0 AND MOD(id,stat_id)=MOD(acct_id,stat_id);
OPTIMIZE TABLE t1;
Table Op Msg_type Msg_text
test.t1 optimize status OK
SELECT COUNT(*) FROM t1;
COUNT(*)
40960
SELECT COUNT(*) FROM t1 WHERE acct_id=785;
COUNT(*)
8702
EXPLAIN SELECT COUNT(*) FROM t1 WHERE stat_id IN (1,3) AND acct_id=785;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range idx1,idx2 idx1 9 NULL 2 Using where; Using index
INSERT INTO t2 SELECT * FROM t1;
OPTIMIZE TABLE t2;
Table Op Msg_type Msg_text
test.t2 optimize status OK
EXPLAIN SELECT COUNT(*) FROM t2 WHERE stat_id IN (1,3) AND acct_id=785;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t2 range idx1,idx2 idx1 9 NULL 2 Using where; Using index
DROP TABLE t1,t2;
create table t1(a int) engine=innodb;
alter table t1 comment '123';
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`a` int(11) default NULL
) ENGINE=InnoDB DEFAULT CHARSET=latin1 COMMENT='123'
drop table t1;
CREATE TABLE t1 (a CHAR(2), KEY (a)) ENGINE = InnoDB DEFAULT CHARSET=UTF8;
INSERT INTO t1 VALUES ('uk'),('bg');
SELECT * FROM t1 WHERE a = 'uk';
a
uk
DELETE FROM t1 WHERE a = 'uk';
SELECT * FROM t1 WHERE a = 'uk';
a
UPDATE t1 SET a = 'us' WHERE a = 'uk';
SELECT * FROM t1 WHERE a = 'uk';
a
CREATE TABLE t2 (a CHAR(2), KEY (a)) ENGINE = InnoDB;
INSERT INTO t2 VALUES ('uk'),('bg');
SELECT * FROM t2 WHERE a = 'uk';
a
uk
DELETE FROM t2 WHERE a = 'uk';
SELECT * FROM t2 WHERE a = 'uk';
a
INSERT INTO t2 VALUES ('uk');
UPDATE t2 SET a = 'us' WHERE a = 'uk';
SELECT * FROM t2 WHERE a = 'uk';
a
CREATE TABLE t3 (a CHAR(2), KEY (a)) ENGINE = MyISAM;
INSERT INTO t3 VALUES ('uk'),('bg');
SELECT * FROM t3 WHERE a = 'uk';
a
uk
DELETE FROM t3 WHERE a = 'uk';
SELECT * FROM t3 WHERE a = 'uk';
a
INSERT INTO t3 VALUES ('uk');
UPDATE t3 SET a = 'us' WHERE a = 'uk';
SELECT * FROM t3 WHERE a = 'uk';
a
DROP TABLE t1,t2,t3;
create table t1 (a int) engine=innodb;
select * from t2;
ERROR 42S02: Table 'test.t2' doesn't exist
drop table t1;
drop table t2;
ERROR 42S02: Unknown table 't2'
create table t2 (a int);
drop table t2;
CREATE TABLE t1 (a INT) ENGINE=InnoDB;
CREATE TABLE t2 (a INT) ENGINE=InnoDB;
switch to connection c1
SET AUTOCOMMIT=0;
INSERT INTO t2 VALUES (1);
switch to connection c2
SET AUTOCOMMIT=0;
LOCK TABLES t1 READ, t2 READ;
ERROR HY000: Lock wait timeout exceeded; try restarting transaction
switch to connection c1
COMMIT;
INSERT INTO t1 VALUES (1);
switch to connection default
SET AUTOCOMMIT=default;
DROP TABLE t1,t2;
CREATE TABLE t1 (
id int NOT NULL auto_increment PRIMARY KEY,
b int NOT NULL,
c datetime NOT NULL,
INDEX idx_b(b),
INDEX idx_c(c)
) ENGINE=InnoDB;
CREATE TABLE t2 (
b int NOT NULL auto_increment PRIMARY KEY,
c datetime NOT NULL
) ENGINE= MyISAM;
INSERT INTO t2(c) VALUES ('2007-01-01');
INSERT INTO t2(c) SELECT c FROM t2;
INSERT INTO t2(c) SELECT c FROM t2;
INSERT INTO t2(c) SELECT c FROM t2;
INSERT INTO t2(c) SELECT c FROM t2;
INSERT INTO t2(c) SELECT c FROM t2;
INSERT INTO t2(c) SELECT c FROM t2;
INSERT INTO t2(c) SELECT c FROM t2;
INSERT INTO t2(c) SELECT c FROM t2;
INSERT INTO t2(c) SELECT c FROM t2;
INSERT INTO t2(c) SELECT c FROM t2;
INSERT INTO t1(b,c) SELECT b,c FROM t2;
UPDATE t2 SET c='2007-01-02';
INSERT INTO t1(b,c) SELECT b,c FROM t2;
UPDATE t2 SET c='2007-01-03';
INSERT INTO t1(b,c) SELECT b,c FROM t2;
set @@sort_buffer_size=8192;
SELECT COUNT(*) FROM t1;
COUNT(*)
3072
EXPLAIN
SELECT COUNT(*) FROM t1
WHERE (c >= '2007-01-02' AND c <= '2007-01-03') OR b >= 1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL idx_b,idx_c NULL NULL NULL # Using where
SELECT COUNT(*) FROM t1
WHERE (c >= '2007-01-02' AND c <= '2007-01-03') OR b >= 1;
COUNT(*)
3072
EXPLAIN
SELECT COUNT(*) FROM t1 FORCE INDEX(idx_b, idx_c)
WHERE (c >= '2007-01-02' AND c <= '2007-01-03') OR b >= 1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index_merge idx_b,idx_c idx_c,idx_b 8,4 NULL # Using sort_union(idx_c,idx_b); Using where
SELECT COUNT(*) FROM t1 FORCE INDEX(idx_b, idx_c)
WHERE (c >= '2007-01-02' AND c <= '2007-01-03') OR b >= 1;
COUNT(*)
3072
set @@sort_buffer_size=default;
DROP TABLE t1,t2;
drop table if exists t1;
create table t1 (a int) engine=innodb;
alter table t1 alter a set default 1;
drop table t1;
Bug#24918 drop table and lock / inconsistent between
perm and temp tables
Check transactional tables under LOCK TABLES
drop table if exists t24918, t24918_tmp, t24918_trans, t24918_trans_tmp,
t24918_access;
create table t24918_access (id int);
create table t24918 (id int) engine=myisam;
create temporary table t24918_tmp (id int) engine=myisam;
create table t24918_trans (id int) engine=innodb;
create temporary table t24918_trans_tmp (id int) engine=innodb;
lock table t24918 write, t24918_tmp write, t24918_trans write, t24918_trans_tmp write;
drop table t24918;
select * from t24918_access;
ERROR HY000: Table 't24918_access' was not locked with LOCK TABLES
drop table t24918_trans;
select * from t24918_access;
ERROR HY000: Table 't24918_access' was not locked with LOCK TABLES
drop table t24918_trans_tmp;
select * from t24918_access;
ERROR HY000: Table 't24918_access' was not locked with LOCK TABLES
drop table t24918_tmp;
select * from t24918_access;
ERROR HY000: Table 't24918_access' was not locked with LOCK TABLES
unlock tables;
drop table t24918_access;
CREATE TABLE t1 (a int, b int, PRIMARY KEY (a), KEY bkey (b)) ENGINE=InnoDB;
INSERT INTO t1 VALUES (1,2),(3,2),(2,2),(4,2),(5,2),(6,2),(7,2),(8,2);
INSERT INTO t1 SELECT a + 8, 2 FROM t1;
INSERT INTO t1 SELECT a + 16, 1 FROM t1;
EXPLAIN SELECT * FROM t1 WHERE b=2 ORDER BY a;
id 1
select_type SIMPLE
table t1
type ref
possible_keys bkey
key bkey
key_len 5
ref const
rows 16
Extra Using where; Using index
SELECT * FROM t1 WHERE b=2 ORDER BY a;
a b
1 2
2 2
3 2
4 2
5 2
6 2
7 2
8 2
9 2
10 2
11 2
12 2
13 2
14 2
15 2
16 2
EXPLAIN SELECT * FROM t1 WHERE b BETWEEN 1 AND 2 ORDER BY a;
id 1
select_type SIMPLE
table t1
type range
possible_keys bkey
key bkey
key_len 5
ref NULL
rows 16
Extra Using where; Using index; Using filesort
SELECT * FROM t1 WHERE b BETWEEN 1 AND 2 ORDER BY a;
a b
1 2
2 2
3 2
4 2
5 2
6 2
7 2
8 2
9 2
10 2
11 2
12 2
13 2
14 2
15 2
16 2
17 1
18 1
19 1
20 1
21 1
22 1
23 1
24 1
25 1
26 1
27 1
28 1
29 1
30 1
31 1
32 1
EXPLAIN SELECT * FROM t1 WHERE b BETWEEN 1 AND 2 ORDER BY b,a;
id 1
select_type SIMPLE
table t1
type range
possible_keys bkey
key bkey
key_len 5
ref NULL
rows 16
Extra Using where; Using index
SELECT * FROM t1 WHERE b BETWEEN 1 AND 2 ORDER BY b,a;
a b
17 1
18 1
19 1
20 1
21 1
22 1
23 1
24 1
25 1
26 1
27 1
28 1
29 1
30 1
31 1
32 1
1 2
2 2
3 2
4 2
5 2
6 2
7 2
8 2
9 2
10 2
11 2
12 2
13 2
14 2
15 2
16 2
CREATE TABLE t2 (a int, b int, c int, PRIMARY KEY (a), KEY bkey (b,c))
ENGINE=InnoDB;
INSERT INTO t2 VALUES (1,1,1),(3,1,1),(2,1,1),(4,1,1);
INSERT INTO t2 SELECT a + 4, 1, 1 FROM t2;
INSERT INTO t2 SELECT a + 8, 1, 1 FROM t2;
EXPLAIN SELECT * FROM t2 WHERE b=1 ORDER BY a;
id 1
select_type SIMPLE
table t2
type ref
possible_keys bkey
key bkey
key_len 5
ref const
rows 8
Extra Using where; Using index; Using filesort
SELECT * FROM t2 WHERE b=1 ORDER BY a;
a b c
1 1 1
2 1 1
3 1 1
4 1 1
5 1 1
6 1 1
7 1 1
8 1 1
9 1 1
10 1 1
11 1 1
12 1 1
13 1 1
14 1 1
15 1 1
16 1 1
EXPLAIN SELECT * FROM t2 WHERE b=1 AND c=1 ORDER BY a;
id 1
select_type SIMPLE
table t2
type ref
possible_keys bkey
key bkey
key_len 10
ref const,const
rows 8
Extra Using where; Using index
SELECT * FROM t2 WHERE b=1 AND c=1 ORDER BY a;
a b c
1 1 1
2 1 1
3 1 1
4 1 1
5 1 1
6 1 1
7 1 1
8 1 1
9 1 1
10 1 1
11 1 1
12 1 1
13 1 1
14 1 1
15 1 1
16 1 1
EXPLAIN SELECT * FROM t2 WHERE b=1 AND c=1 ORDER BY b,c,a;
id 1
select_type SIMPLE
table t2
type ref
possible_keys bkey
key bkey
key_len 10
ref const,const
rows 8
Extra Using where; Using index
SELECT * FROM t2 WHERE b=1 AND c=1 ORDER BY b,c,a;
a b c
1 1 1
2 1 1
3 1 1
4 1 1
5 1 1
6 1 1
7 1 1
8 1 1
9 1 1
10 1 1
11 1 1
12 1 1
13 1 1
14 1 1
15 1 1
16 1 1
EXPLAIN SELECT * FROM t2 WHERE b=1 AND c=1 ORDER BY c,a;
id 1
select_type SIMPLE
table t2
type ref
possible_keys bkey
key bkey
key_len 10
ref const,const
rows 8
Extra Using where; Using index
SELECT * FROM t2 WHERE b=1 AND c=1 ORDER BY c,a;
a b c
1 1 1
2 1 1
3 1 1
4 1 1
5 1 1
6 1 1
7 1 1
8 1 1
9 1 1
10 1 1
11 1 1
12 1 1
13 1 1
14 1 1
15 1 1
16 1 1
DROP TABLE t1,t2;
CREATE TABLE t1 (a INT, PRIMARY KEY (a)) ENGINE=InnoDB;
INSERT INTO t1 VALUES (1),(2),(3),(4),(5),(6),(7),(8);
INSERT INTO t1 SELECT a + 8 FROM t1;
INSERT INTO t1 SELECT a + 16 FROM t1;
CREATE PROCEDURE p1 ()
BEGIN
DECLARE i INT DEFAULT 50;
DECLARE cnt INT;
START TRANSACTION;
ALTER TABLE t1 ENGINE=InnoDB;
COMMIT;
START TRANSACTION;
WHILE (i > 0) DO
SET i = i - 1;
SELECT COUNT(*) INTO cnt FROM t1 LOCK IN SHARE MODE;
END WHILE;
COMMIT;
END;|
CALL p1();
CALL p1();
CALL p1();
DROP PROCEDURE p1;
DROP TABLE t1;
create table t1(a text) engine=innodb default charset=utf8;
insert into t1 values('aaa');
alter table t1 add index(a(1024));
Warnings:
Warning 1071 Specified key was too long; max key length is 767 bytes
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`a` text,
KEY `a` (`a`(255))
) ENGINE=InnoDB DEFAULT CHARSET=utf8
drop table t1;
CREATE TABLE t1 (
a INT,
b INT,
KEY (b)
) ENGINE=InnoDB;
INSERT INTO t1 VALUES (1,10), (2,10), (2,20), (3,30);
START TRANSACTION;
SELECT * FROM t1 WHERE b=20 FOR UPDATE;
a b
2 20
START TRANSACTION;
SELECT * FROM t1 WHERE b=10 ORDER BY A FOR UPDATE;
a b
1 10
2 10
ROLLBACK;
ROLLBACK;
DROP TABLE t1;
CREATE TABLE t1(
a INT,
b INT NOT NULL,
c INT NOT NULL,
d INT,
UNIQUE KEY (c,b)
) engine=innodb;
INSERT INTO t1 VALUES (1,1,1,50), (1,2,3,40), (2,1,3,4);
EXPLAIN SELECT c,b,d FROM t1 GROUP BY c,b,d;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 3 Using filesort
SELECT c,b,d FROM t1 GROUP BY c,b,d;
c b d
1 1 50
3 1 4
3 2 40
EXPLAIN SELECT c,b,d FROM t1 GROUP BY c,b,d ORDER BY NULL;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 3
SELECT c,b,d FROM t1 GROUP BY c,b,d ORDER BY NULL;
c b d
1 1 50
3 1 4
3 2 40
EXPLAIN SELECT c,b,d FROM t1 ORDER BY c,b,d;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 3 Using filesort
SELECT c,b,d FROM t1 ORDER BY c,b,d;
c b d
1 1 50
3 1 4
3 2 40
EXPLAIN SELECT c,b,d FROM t1 GROUP BY c,b;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index NULL c 8 NULL 3
SELECT c,b,d FROM t1 GROUP BY c,b;
c b d
1 1 50
3 1 4
3 2 40
EXPLAIN SELECT c,b FROM t1 GROUP BY c,b;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index NULL c 8 NULL 3 Using index
SELECT c,b FROM t1 GROUP BY c,b;
c b
1 1
3 1
3 2
DROP TABLE t1;
CREATE TABLE t1 (a INT, b INT, PRIMARY KEY (a), INDEX b (b)) ENGINE=InnoDB;
INSERT INTO t1(a,b) VALUES (1,1), (2,2), (3,2);
EXPLAIN SELECT * FROM t1 WHERE b=2 ORDER BY a ASC;
id 1
select_type SIMPLE
table t1
type ref
possible_keys b
key b
key_len 5
ref const
rows 1
Extra Using where; Using index
SELECT * FROM t1 WHERE b=2 ORDER BY a ASC;
a b
2 2
3 2
EXPLAIN SELECT * FROM t1 WHERE b=2 ORDER BY a DESC;
id 1
select_type SIMPLE
table t1
type ref
possible_keys b
key b
key_len 5
ref const
rows 1
Extra Using where; Using index
SELECT * FROM t1 WHERE b=2 ORDER BY a DESC;
a b
3 2
2 2
EXPLAIN SELECT * FROM t1 ORDER BY b ASC, a ASC;
id 1
select_type SIMPLE
table t1
type index
possible_keys NULL
key b
key_len 5
ref NULL
rows 3
Extra Using index
SELECT * FROM t1 ORDER BY b ASC, a ASC;
a b
1 1
2 2
3 2
EXPLAIN SELECT * FROM t1 ORDER BY b DESC, a DESC;
id 1
select_type SIMPLE
table t1
type index
possible_keys NULL
key b
key_len 5
ref NULL
rows 3
Extra Using index
SELECT * FROM t1 ORDER BY b DESC, a DESC;
a b
3 2
2 2
1 1
EXPLAIN SELECT * FROM t1 ORDER BY b ASC, a DESC;
id 1
select_type SIMPLE
table t1
type index
possible_keys NULL
key b
key_len 5
ref NULL
rows 3
Extra Using index; Using filesort
SELECT * FROM t1 ORDER BY b ASC, a DESC;
a b
1 1
3 2
2 2
EXPLAIN SELECT * FROM t1 ORDER BY b DESC, a ASC;
id 1
select_type SIMPLE
table t1
type index
possible_keys NULL
key b
key_len 5
ref NULL
rows 3
Extra Using index; Using filesort
SELECT * FROM t1 ORDER BY b DESC, a ASC;
a b
2 2
3 2
1 1
DROP TABLE t1;
End of 5.0 tests
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