call mtr.add_suppression("Can't find record in .*");
ALTER DATABASE test CHARACTER SET latin1 COLLATE latin1_swedish_ci; SET SESSION DEFAULT_STORAGE_ENGINE = MEMORY;
drop table if exists t1,t2,t3,t4;
drop database if exists mysqltest;
create table t1 (id int unsigned not null auto_increment, code tinyint unsigned not null, name char(20) not null, primary key (id), key (code), unique (name)) engine=MyISAM;
insert into t1 (code, name) values (1, 'Tim'), (1, 'Monty'), (2, 'David'), (2, 'Erik'), (3, 'Sasha'), (3, 'Jeremy'), (4, 'Matt');
select id, code, name from t1 order by id;
id code name 11 Tim 21 Monty 32 David 42 Erik 53 Sasha 63 Jeremy 74 Matt
update ignore t1 set id = 8, name = 'Sinisa' where id < 3;
select id, code, name from t1 order by id;
id code name 21 Monty 32 David 42 Erik 53 Sasha 63 Jeremy 74 Matt 81 Sinisa
update ignore t1 set id = id + 10, name = 'Ralph' where id < 4;
select id, code, name from t1 order by id;
id code name 32 David 42 Erik 53 Sasha 63 Jeremy 74 Matt 81 Sinisa 121 Ralph
drop table t1;
CREATE TABLE t1 (
id int(11) NOT NULL auto_increment,
parent_id int(11) DEFAULT '0'NOT NULL,
level tinyint(4) DEFAULT '0'NOT NULL,
PRIMARY KEY (id),
KEY parent_id (parent_id),
KEY level (level)
) engine=MyISAM;
INSERT INTO t1 VALUES (1,0,0),(3,1,1),(4,1,1),(8,2,2),(9,2,2),(17,3,2),(22,4,2),(24,4,2),(28,5,2),(29,5,2),(30,5,2),(31,6,2),(32,6,2),(33,6,2),(203,7,2),(202,7,2),(20,3,2),(157,0,0),(193,5,2),(40,7,2),(2,1,1),(15,2,2),(6,1,1),(34,6,2),(35,6,2),(16,3,2),(7,1,1),(36,7,2),(18,3,2),(26,5,2),(27,5,2),(183,4,2),(38,7,2),(25,5,2),(37,7,2),(21,4,2),(19,3,2),(5,1,1),(179,5,2);
update t1 set parent_id=parent_id+100;
select * from t1 where parent_id=102;
id parent_id level 81022 91022 151022
update t1 set id=id+1000;
update t1 set id=1024 where id=1009;
Got one of the listed errors
select * from t1;
id parent_id level 10011000 10031011 10041011 10081022 10091022 10171032 10221042 10241042 10281052 10291052 10301052 10311062 10321062 10331062 12031072 12021072 10201032 11571000 11931052 10401072 10021011 10151022 10061011 10341062 10351062 10161032 10071011 10361072 10181032 10261052 10271052 11831042 10381072 10251052 10371072 10211042 10191032 10051011 11791052
update ignore t1 set id=id+1;
select * from t1;
id parent_id level 10011000 10031011 10041011 10081022 10101022 10171032 10231042 10241042 10281052 10291052 10301052 10311062 10321062 10331062 12041072 12031072 10201032 11581000 11941052 10411072 10021011 10151022 10061011 10341062 10351062 10161032 10071011 10361072 10181032 10261052 10271052 11841042 10391072 10251052 10381072 10221042 10191032 10051011 11801052
update ignore t1 set id=1023 where id=1010;
select * from t1 where parent_id=102;
id parent_id level 10081022 10101022 10151022
explain select level from t1 where level=1;
id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 ref level level 1 const # Using index
explain select level,id from t1 where level=1;
id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 ref level level 1 const #
explain select level,id,parent_id from t1 where level=1;
id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 ref level level 1 const #
select level,id from t1 where level=1;
level id 11003 11004 11002 11006 11007 11005
select level,id,parent_id from t1 where level=1;
level id parent_id 11003101 11004101 11002101 11006101 11007101 11005101
optimize table t1;
Table Op Msg_type Msg_text
test.t1 optimize status OK
show keys from t1;
Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment Ignored
t1 0 PRIMARY 1 id A # NULL NULL BTREE NO
t1 1 parent_id 1 parent_id A # NULL NULL BTREE NO
t1 1 level 1 level A # NULL NULL BTREE NO
drop table t1;
CREATE TABLE t1 (
gesuchnr int(11) DEFAULT '0'NOT NULL,
benutzer_id int(11) DEFAULT '0'NOT NULL,
PRIMARY KEY (gesuchnr,benutzer_id)
) engine=MyISAM; replace into t1 (gesuchnr,benutzer_id) values (2,1); replace into t1 (gesuchnr,benutzer_id) values (1,1); replace into t1 (gesuchnr,benutzer_id) values (1,1);
select * from t1;
gesuchnr benutzer_id 11 21
drop table t1;
create table t1 (a int) engine=MyISAM;
insert into t1 values (1), (2);
optimize table t1;
Table Op Msg_type Msg_text
test.t1 optimize status OK
delete from t1 where a = 1;
select * from t1;
a 2
check table t1;
Table Op Msg_type Msg_text
test.t1 check status OK
drop table t1;
create table t1 (a int,b varchar(20)) engine=MyISAM;
insert into t1 values (1,""), (2,"testing");
delete from t1 where a = 1;
select * from t1;
a b 2 testing
create index skr on t1 (a);
insert into t1 values (3,""), (4,"testing");
analyze table t1;
Table Op Msg_type Msg_text
test.t1 analyze status Engine-independent statistics collected
test.t1 analyze status OK
show keys from t1;
Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment Ignored
t1 1 skr 1 a A # NULL NULL YES BTREE NO
drop table t1;
create table t1 (a int,b varchar(20),key(a)) engine=MyISAM;
insert into t1 values (1,""), (2,"testing");
select * from t1 where a = 1;
a b 1
drop table t1;
CREATE TABLE t1 (
user_id int(10) DEFAULT '0'NOT NULL,
name varchar(100),
phone varchar(100),
ref_email varchar(100) DEFAULT ''NOT NULL,
detail varchar(200),
PRIMARY KEY (user_id,ref_email)
)engine=MyISAM;
INSERT INTO t1 VALUES (10292,'sanjeev','29153373','sansh777@hotmail.com','xxx'),(10292,'shirish','2333604','shirish@yahoo.com','ddsds'),(10292,'sonali','323232','sonali@bolly.com','filmstar');
select * from t1 where user_id=10292;
user_id name phone ref_email detail 10292 sanjeev 29153373 sansh777@hotmail.com xxx 10292 shirish 2333604 shirish@yahoo.com ddsds 10292 sonali 323232 sonali@bolly.com filmstar
INSERT INTO t1 VALUES (10291,'sanjeev','29153373','sansh777@hotmail.com','xxx'),(10293,'shirish','2333604','shirish@yahoo.com','ddsds');
select * from t1 where user_id=10292;
user_id name phone ref_email detail 10292 sanjeev 29153373 sansh777@hotmail.com xxx 10292 shirish 2333604 shirish@yahoo.com ddsds 10292 sonali 323232 sonali@bolly.com filmstar
select * from t1 where user_id>=10292;
user_id name phone ref_email detail 10292 sanjeev 29153373 sansh777@hotmail.com xxx 10292 shirish 2333604 shirish@yahoo.com ddsds 10292 sonali 323232 sonali@bolly.com filmstar 10293 shirish 2333604 shirish@yahoo.com ddsds
select * from t1 where user_id>10292;
user_id name phone ref_email detail 10293 shirish 2333604 shirish@yahoo.com ddsds
select * from t1 where user_id<10292;
user_id name phone ref_email detail 10291 sanjeev 29153373 sansh777@hotmail.com xxx
drop table t1;
CREATE TABLE t1 (a int not null, b int not null,c int not null,
key(a),primary key(a,b), unique(c),key(a),unique(b)) ENGINE = MyISAM;
Warnings:
Note 1831 Duplicate index `a_2`. This is deprecated and will be disallowed in a future release
show index from t1;
Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment Ignored
t1 0 PRIMARY 1 a A # NULL NULL BTREE NO
t1 0 PRIMARY 2 b A # NULL NULL BTREE NO
t1 0 c 1 c A # NULL NULL BTREE NO
t1 0 b 1 b A # NULL NULL BTREE NO
t1 1 a 1 a A # NULL NULL BTREE NO
t1 1 a_2 1 a A # NULL NULL BTREE NO
drop table t1;
create table t1 (col1 int not null, col2 char(4) not null, primary key(col1)) ENGINE = MEMORY;
alter table t1 engine=MyISAM;
insert into t1 values ('1','1'),('5','2'),('2','3'),('3','4'),('4','4');
select * from t1;
col1 col2 11 52 23 34 44
update t1 set col2='7' where col1='4';
select * from t1;
col1 col2 11 52 23 34 47
alter table t1 add co3 int not null;
select * from t1;
col1 col2 co3 110 520 230 340 470
update t1 set col2='9' where col1='2';
select * from t1;
col1 col2 co3 110 520 290 340 470
drop table t1;
create table t1 (a int not null , b int, primary key (a)) engine = MyISAM;
create table t2 (a int not null , b int, primary key (a)) engine = MEMORY;
insert into t1 VALUES (1,3) , (2,3), (3,3);
select * from t1;
a b 13 23 33
insert into t2 select * from t1;
select * from t2;
a b 13 23 33
delete from t1 where b = 3;
select * from t1;
a b
insert into t1 select * from t2;
select * from t1;
a b 33 23 13
select * from t2;
a b 13 23 33
drop table t1,t2;
CREATE TABLE t1 (
id int(11) NOT NULL auto_increment,
ggid varchar(32) binary DEFAULT ''NOT NULL,
email varchar(64) DEFAULT ''NOT NULL,
passwd varchar(32) binary DEFAULT ''NOT NULL,
PRIMARY KEY (id),
UNIQUE ggid (ggid)
) ENGINE=MyISAM;
insert into t1 (ggid,passwd) values ('test1','xxx');
insert into t1 (ggid,passwd) values ('test2','yyy');
insert into t1 (ggid,passwd) values ('test2','this will fail'); ERROR23000: Duplicate entry 'test2' for key 'ggid'
insert into t1 (ggid,id) values ('this will fail',1); ERROR23000: Duplicate entry '1' for key 'PRIMARY'
select * from t1 where ggid='test1';
id ggid email passwd 1 test1 xxx
select * from t1 where passwd='xxx';
id ggid email passwd 1 test1 xxx
select * from t1 where id=2;
id ggid email passwd 2 test2 yyy replace into t1 (ggid,id) values ('this will work',1); replace into t1 (ggid,passwd) values ('test2','this will work');
update t1 set id=100,ggid='test2' where id=1; ERROR23000: Duplicate entry 'test2' for key 'ggid'
select * from t1;
id ggid email passwd 1 this will work 3 test2 this will work
select * from t1 where id=1;
id ggid email passwd 1 this will work
select * from t1 where id=999;
id ggid email passwd
drop table t1;
CREATE TABLE t1 (
user_name varchar(12),
password text,
subscribed char(1),
user_id int(11) DEFAULT '0'NOT NULL,
quota bigint(20),
weight double,
access_date date,
access_time time,
approved datetime,
dummy_primary_key int(11) NOT NULL auto_increment,
PRIMARY KEY (dummy_primary_key)
) ENGINE=MyISAM;
INSERT INTO t1 VALUES ('user_0','somepassword','N',0,0,0,'2000-09-07','23:06:59','2000-09-07 23:06:59',1);
INSERT INTO t1 VALUES ('user_1','somepassword','Y',1,1,1,'2000-09-07','23:06:59','2000-09-07 23:06:59',2);
INSERT INTO t1 VALUES ('user_2','somepassword','N',2,2,1.4142135623731,'2000-09-07','23:06:59','2000-09-07 23:06:59',3);
INSERT INTO t1 VALUES ('user_3','somepassword','Y',3,3,1.7320508075689,'2000-09-07','23:06:59','2000-09-07 23:06:59',4);
INSERT INTO t1 VALUES ('user_4','somepassword','N',4,4,2,'2000-09-07','23:06:59','2000-09-07 23:06:59',5);
select user_name, password , subscribed, user_id, quota, weight, access_date, access_time, approved, dummy_primary_key from t1 order by user_name;
user_name password subscribed user_id quota weight access_date access_time approved dummy_primary_key
user_0 somepassword N 0002000-09-0723:06:592000-09-0723:06:591
user_1 somepassword Y 1112000-09-0723:06:592000-09-0723:06:592
user_2 somepassword N 221.41421356237312000-09-0723:06:592000-09-0723:06:593
user_3 somepassword Y 331.73205080756892000-09-0723:06:592000-09-0723:06:594
user_4 somepassword N 4422000-09-0723:06:592000-09-0723:06:595
drop table t1;
CREATE TABLE t1 (
id int(11) NOT NULL auto_increment,
parent_id int(11) DEFAULT '0'NOT NULL,
level tinyint(4) DEFAULT '0'NOT NULL,
KEY (id),
KEY parent_id (parent_id),
KEY level (level)
) engine=MyISAM;
INSERT INTO t1 VALUES (1,0,0),(3,1,1),(4,1,1),(8,2,2),(9,2,2),(17,3,2),(22,4,2),(24,4,2),(28,5,2),(29,5,2),(30,5,2),(31,6,2),(32,6,2),(33,6,2),(203,7,2),(202,7,2),(20,3,2),(157,0,0),(193,5,2),(40,7,2),(2,1,1),(15,2,2),(6,1,1),(34,6,2),(35,6,2),(16,3,2),(7,1,1),(36,7,2),(18,3,2),(26,5,2),(27,5,2),(183,4,2),(38,7,2),(25,5,2),(37,7,2),(21,4,2),(19,3,2),(5,1,1);
INSERT INTO t1 values (179,5,2);
update t1 set parent_id=parent_id+100;
select * from t1 where parent_id=102;
id parent_id level 81022 91022 151022
update t1 set id=id+1000;
update t1 set id=1024 where id=1009;
select * from t1;
id parent_id level 10011000 10031011 10041011 10081022 10241022 10171032 10221042 10241042 10281052 10291052 10301052 10311062 10321062 10331062 12031072 12021072 10201032 11571000 11931052 10401072 10021011 10151022 10061011 10341062 10351062 10161032 10071011 10361072 10181032 10261052 10271052 11831042 10381072 10251052 10371072 10211042 10191032 10051011 11791052
update ignore t1 set id=id+1;
select * from t1;
id parent_id level 10021000 10041011 10051011 10091022 10251022 10181032 10231042 10251042 10291052 10301052 10311052 10321062 10331062 10341062 12041072 12031072 10211032 11581000 11941052 10411072 10031011 10161022 10071011 10351062 10361062 10171032 10081011 10371072 10191032 10271052 10281052 11841042 10391072 10261052 10381072 10221042 10201032 10061011 11801052
update ignore t1 set id=1023 where id=1010;
select * from t1 where parent_id=102;
id parent_id level 10091022 10251022 10161022
explain select level from t1 where level=1;
id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 ref level level 1 const # Using index
select level,id from t1 where level=1;
level id 11004 11005 11003 11007 11008 11006
select level,id,parent_id from t1 where level=1;
level id parent_id 11004101 11005101 11003101 11007101 11008101 11006101
select level,id from t1 where level=1 order by id;
level id 11003 11004 11005 11006 11007 11008
delete from t1 where level=1;
select * from t1;
id parent_id level 10021000 10091022 10251022 10181032 10231042 10251042 10291052 10301052 10311052 10321062 10331062 10341062 12041072 12031072 10211032 11581000 11941052 10411072 10161022 10351062 10361062 10171032 10371072 10191032 10271052 10281052 11841042 10391072 10261052 10381072 10221042 10201032 11801052
drop table t1;
CREATE TABLE t1 (
sca_code char(6) NOT NULL,
cat_code char(6) NOT NULL,
sca_desc varchar(50),
lan_code char(2) NOT NULL,
sca_pic varchar(100),
sca_sdesc varchar(50),
sca_sch_desc varchar(16),
PRIMARY KEY (sca_code, cat_code, lan_code),
INDEX sca_pic (sca_pic)
) engine = MyISAM ;
INSERT INTO t1 ( sca_code, cat_code, sca_desc, lan_code, sca_pic, sca_sdesc, sca_sch_desc) VALUES ( 'PD', 'J', 'PENDANT', 'EN', NULL, NULL, 'PENDANT'),( 'RI', 'J', 'RING', 'EN', NULL, NULL, 'RING'),( 'QQ', 'N', 'RING', 'EN', 'not null', NULL, 'RING');
select count(*) from t1 where sca_code = 'PD';
count(*) 1
select count(*) from t1 where sca_code <= 'PD';
count(*) 1
select count(*) from t1 where sca_pic is null;
count(*) 2
alter table t1 drop index sca_pic, add index sca_pic (cat_code, sca_pic);
select count(*) from t1 where sca_code='PD'and sca_pic is null;
count(*) 1
select count(*) from t1 where cat_code='E';
count(*) 0
alter table t1 drop index sca_pic, add index (sca_pic, cat_code);
select count(*) from t1 where sca_code='PD'and sca_pic is null;
count(*) 1
select count(*) from t1 where sca_pic >= 'n';
count(*) 1
select sca_pic from t1 where sca_pic is null;
sca_pic
NULL
NULL
update t1 set sca_pic="test" where sca_pic is null;
delete from t1 where sca_code='pd';
drop table t1; set @a:=now();
CREATE TABLE t1 (a int not null, b timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP, primary key (a)) engine=MyISAM;
insert into t1 (a) values(1),(2),(3);
select t1.a from t1 natural join t1 as t2 where t1.b >= @a order by t1.a;
a 1 2 3
select a from t1 natural join t1 as t2 where b >= @a order by a;
a 1 2 3
update t1 set a=5 where a=1;
select a from t1;
a 2 3 5
drop table t1;
create table t1 (a varchar(100) not null, primary key(a), b int not null) engine=MyISAM;
insert into t1 values("hello",1),("world",2);
select * from t1 order by b desc;
a b
world 2
hello 1
optimize table t1;
Table Op Msg_type Msg_text
test.t1 optimize status OK
show keys from t1;
Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment Ignored
t1 0 PRIMARY 1 a A # NULL NULL BTREE NO
drop table t1;
create table t1 (i int, j int ) ENGINE=MyISAM;
insert into t1 values (1,2);
select * from t1 where i=1and j=2;
i j 12
create index ax1 on t1 (i,j);
select * from t1 where i=1and j=2;
i j 12
drop table t1;
CREATE TABLE t1 (
a int3 unsigned NOT NULL,
b int1 unsigned NOT NULL,
UNIQUE (a, b)
) ENGINE = MyISAM;
INSERT INTO t1 VALUES (1, 1);
SELECT MIN(B),MAX(b) FROM t1 WHERE t1.a = 1; MIN(B) MAX(b) 11
drop table t1;
CREATE TABLE t1 (a int unsigned NOT NULL) engine=MyISAM;
INSERT INTO t1 VALUES (1);
SELECT * FROM t1;
a 1
DROP TABLE t1;
create table t1 (a int primary key,b int, c int, d int, e int, f int, g int, h int, i int, j int, k int, l int, m int, n int, o int, p int, q int, r int, s int, t int, u int, v int, w int, x int, y int, z int, a1 int, a2 int, a3 int, a4 int, a5 int, a6 int, a7 int, a8 int, a9 int, b1 int, b2 int, b3 int, b4 int, b5 int, b6 int) engine = MyISAM;
insert into t1 values (1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1);
explain select * from t1 where a > 0and a < 50;
id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 system PRIMARY NULL NULL NULL #
drop table t1;
create table t1 (id int NOT NULL,id2 int NOT NULL,id3 int NOT NULL,dummy1 char(30),primary key (id,id2),index index_id3 (id3)) engine=MyISAM;
insert into t1 values (0,0,0,'ABCDEFGHIJ'),(2,2,2,'BCDEFGHIJK'),(1,1,1,'CDEFGHIJKL');
LOCK TABLES t1 WRITE;
insert into t1 values (99,1,2,'D'),(1,1,2,'D'); ERROR23000: Duplicate entry '1-1' for key 'PRIMARY'
select id from t1;
id 0 1 2 99
select id from t1;
id 0 1 2 99
UNLOCK TABLES;
DROP TABLE t1;
create table t1 (id int NOT NULL,id2 int NOT NULL,id3 int NOT NULL,dummy1 char(30),primary key (id,id2),index index_id3 (id3)) engine=MyISAM;
insert into t1 values (0,0,0,'ABCDEFGHIJ'),(2,2,2,'BCDEFGHIJK'),(1,1,1,'CDEFGHIJKL');
LOCK TABLES t1 WRITE;
begin;
insert into t1 values (99,1,2,'D'),(1,1,2,'D'); ERROR23000: Duplicate entry '1-1' for key 'PRIMARY'
select id from t1;
id 0 1 2 99
insert ignore into t1 values (100,1,2,'D'),(1,1,99,'D');
Warnings:
Warning 1062 Duplicate entry '1-1' for key 'PRIMARY'
commit;
select id,id3 from t1;
id id3 00 22 11 992 1002
UNLOCK TABLES;
DROP TABLE t1;
create table t1 (a char(20), unique (a(5))) engine=MyISAM;
drop table t1;
create table t1 (a char(20), index (a(5))) engine=MyISAM;
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`a` char(20) DEFAULT NULL,
KEY `a` (`a`(5))
) ENGINE=MyISAM DEFAULT CHARSET=latin1 COLLATE=latin1_swedish_ci
drop table t1;
create temporary table t1 (a int not null auto_increment, primary key(a)) engine=MyISAM;
insert into t1 values (NULL),(NULL),(NULL);
delete from t1 where a=3;
insert into t1 values (NULL);
select * from t1;
a 1 2 4
alter table t1 add b int;
select * from t1;
a b 1 NULL 2 NULL 4 NULL
drop table t1;
create table t1
(
id int auto_increment primary key,
name varchar(32) not null,
value text not null,
uid int not null,
unique key(name,uid)
) engine=MyISAM;
insert into t1 values (1,'one','one value',101),
(2,'two','two value',102),(3,'three','three value',103); set insert_id=5; replace into t1 (value,name,uid) values ('other value','two',102);
delete from t1 where uid=102; set insert_id=5; replace into t1 (value,name,uid) values ('other value','two',102); set insert_id=6; replace into t1 (value,name,uid) values ('other value','two',102);
select * from t1;
id name value uid 1 one one value 101 3 three three value 103 6 two other value 102
drop table t1;
create database mysqltest;
create table mysqltest.t1 (a int not null) engine= MyISAM;
insert into mysqltest.t1 values(1);
create table mysqltest.t2 (a int not null) engine= MEMORY;
insert into mysqltest.t2 values(1);
create table mysqltest.t3 (a int not null) engine= MEMORY;
insert into mysqltest.t3 values(1);
commit;
drop database mysqltest;
show tables from mysqltest; ERROR42000: Unknown database 'mysqltest' set autocommit=0;
create table t1 (a int not null) engine= MyISAM;
insert into t1 values(1),(2);
truncate table t1;
commit;
truncate table t1;
truncate table t1;
select * from t1;
a
insert into t1 values(1),(2);
delete from t1;
select * from t1;
a
commit;
drop table t1; set autocommit=1;
create table t1 (a int not null) engine= MyISAM;
insert into t1 values(1),(2);
truncate table t1;
insert into t1 values(1),(2);
select * from t1;
a 1 2
truncate table t1;
insert into t1 values(1),(2);
delete from t1;
select * from t1;
a
drop table t1;
create table t1 (a int not null, b int not null, c int not null, primary key (a),key(b)) engine=MyISAM;
insert into t1 values (3,3,3),(1,1,1),(2,2,2),(4,4,4);
explain select * from t1 order by a;
id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 ALL NULL NULL NULL NULL # Using filesort
explain select * from t1 order by b;
id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 ALL NULL NULL NULL NULL # Using filesort
explain select * from t1 order by c;
id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 ALL NULL NULL NULL NULL # Using filesort
explain select a from t1 order by a;
id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 index NULL PRIMARY 4 NULL # Using index
explain select b from t1 order by b;
id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 index NULL b 4 NULL # Using index
explain select a,b from t1 order by b;
id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 ALL NULL NULL NULL NULL # Using filesort
explain select a,b from t1;
id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 ALL NULL NULL NULL NULL #
explain select a,b,c from t1;
id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 ALL NULL NULL NULL NULL #
drop table t1;
create table t1 (t int not null default 1, key (t)) engine=MyISAM;
desc t1;
Field Type Null Key Default Extra
t int(11) NO MUL 1
drop table t1;
CREATE TABLE t1 (
number bigint(20) NOT NULL default '0',
cname char(15) NOT NULL default '',
carrier_id smallint(6) NOT NULL default '0',
privacy tinyint(4) NOT NULL default '0',
last_mod_date timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
last_mod_id smallint(6) NOT NULL default '0',
last_app_date timestamp NOT NULL DEFAULT '0000-00-00 00:00:00',
last_app_id smallint(6) default '-1',
version smallint(6) NOT NULL default '0',
assigned_scps int(11) default '0',
status tinyint(4) default '0'
) ENGINE=MyISAM;
INSERT INTO t1 VALUES (4077711111,'SeanWheeler',90,2,20020111112846,500,00000000000000,-1,2,3,1);
INSERT INTO t1 VALUES (9197722223,'berry',90,3,20020111112809,500,20020102114532,501,4,10,0);
INSERT INTO t1 VALUES (650,'San Francisco',0,0,20011227111336,342,00000000000000,-1,1,24,1);
INSERT INTO t1 VALUES (302467,'Sue\'s Subshop',90,3,20020109113241,500,20020102115111,501,7,24,0);
INSERT INTO t1 VALUES (6014911113,'SudzCarwash',520,1,20020102115234,500,20020102115259,501,33,32768,0);
INSERT INTO t1 VALUES (333,'tubs',99,2,20020109113440,501,20020109113440,500,3,10,0);
CREATE TABLE t2 (
number bigint(20) NOT NULL default '0',
cname char(15) NOT NULL default '',
carrier_id smallint(6) NOT NULL default '0',
privacy tinyint(4) NOT NULL default '0',
last_mod_date timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
last_mod_id smallint(6) NOT NULL default '0',
last_app_date timestamp NOT NULL DEFAULT '0000-00-00 00:00:00',
last_app_id smallint(6) default '-1',
version smallint(6) NOT NULL default '0',
assigned_scps int(11) default '0',
status tinyint(4) default '0'
) ENGINE=MyISAM;
INSERT INTO t2 VALUES (4077711111,'SeanWheeler',0,2,20020111112853,500,00000000000000,-1,2,3,1);
INSERT INTO t2 VALUES (9197722223,'berry',90,3,20020111112818,500,20020102114532,501,4,10,0);
INSERT INTO t2 VALUES (650,'San Francisco',90,0,20020109113158,342,00000000000000,-1,1,24,1);
INSERT INTO t2 VALUES (333,'tubs',99,2,20020109113453,501,20020109113453,500,3,10,0);
select * from t1;
number cname carrier_id privacy last_mod_date last_mod_id last_app_date last_app_id version assigned_scps status 4077711111 SeanWheeler 9022002-01-1111:28:465000000-00-0000:00:00 -1231 9197722223 berry 9032002-01-1111:28:095002002-01-0211:45:325014100 650 San Francisco 002001-12-2711:13:363420000-00-0000:00:00 -11241 302467 Sue's Subshop 90 3 2002-01-09 11:32:41 500 2002-01-02 11:51:11 501 7 24 0 6014911113 SudzCarwash 52012002-01-0211:52:345002002-01-0211:52:5950133327680 333 tubs 9922002-01-0911:34:405012002-01-0911:34:405003100
select * from t2;
number cname carrier_id privacy last_mod_date last_mod_id last_app_date last_app_id version assigned_scps status 4077711111 SeanWheeler 022002-01-1111:28:535000000-00-0000:00:00 -1231 9197722223 berry 9032002-01-1111:28:185002002-01-0211:45:325014100 650 San Francisco 9002002-01-0911:31:583420000-00-0000:00:00 -11241 333 tubs 9922002-01-0911:34:535012002-01-0911:34:535003100
delete t1, t2 from t1 left join t2 on t1.number=t2.number where (t1.carrier_id=90and t1.number=t2.number) or (t2.carrier_id=90and t1.number=t2.number) or (t1.carrier_id=90and t2.number is null);
select * from t1;
number cname carrier_id privacy last_mod_date last_mod_id last_app_date last_app_id version assigned_scps status 6014911113 SudzCarwash 52012002-01-0211:52:345002002-01-0211:52:5950133327680 333 tubs 9922002-01-0911:34:405012002-01-0911:34:405003100
select * from t2;
number cname carrier_id privacy last_mod_date last_mod_id last_app_date last_app_id version assigned_scps status 333 tubs 9922002-01-0911:34:535012002-01-0911:34:535003100
select * from t2;
number cname carrier_id privacy last_mod_date last_mod_id last_app_date last_app_id version assigned_scps status 333 tubs 9922002-01-0911:34:535012002-01-0911:34:535003100
drop table t1,t2;
create table t1 (id int unsigned not null auto_increment, code tinyint unsigned not null, name char(20) not null, primary key (id), key (code), unique (name)) engine=MyISAM;
BEGIN; SET SESSION TRANSACTION ISOLATION LEVEL SERIALIZABLE;
SELECT @@transaction_isolation,@@global.transaction_isolation;
@@transaction_isolation @@global.transaction_isolation
SERIALIZABLE REPEATABLE-READ
insert into t1 (code, name) values (1, 'Tim'), (1, 'Monty'), (2, 'David');
select id, code, name from t1 order by id;
id code name 11 Tim 21 Monty 32 David
COMMIT;
BEGIN; SET SESSION TRANSACTION ISOLATION LEVEL REPEATABLE READ;
insert into t1 (code, name) values (2, 'Erik'), (3, 'Sasha');
select id, code, name from t1 order by id;
id code name 11 Tim 21 Monty 32 David 42 Erik 53 Sasha
COMMIT;
BEGIN; SET SESSION TRANSACTION ISOLATION LEVEL READ UNCOMMITTED;
insert into t1 (code, name) values (3, 'Jeremy'), (4, 'Matt');
select id, code, name from t1 order by id;
id code name 11 Tim 21 Monty 32 David 42 Erik 53 Sasha 63 Jeremy 74 Matt
COMMIT;
DROP TABLE t1;
create table t1 (n int(10), d int(10)) engine=MyISAM;
create table t2 (n int(10), d int(10)) engine=MyISAM;
insert into t1 values(1,1),(1,2);
insert into t2 values(1,10),(2,20);
UPDATE t1,t2 SET t1.d=t2.d,t2.d=30 WHERE t1.n=t2.n;
select * from t1;
n d 110 110
select * from t2;
n d 130 220
drop table t1,t2;
create table t1 (a int, b int) engine=MyISAM;
insert into t1 values(20,null);
select t2.b, ifnull(t2.b,"this is null") from t1 as t2 left join t1 as t3 on
t2.b=t3.a;
b ifnull(t2.b,"this is null")
NULL this is null
select t2.b, ifnull(t2.b,"this is null") from t1 as t2 left join t1 as t3 on
t2.b=t3.a order by 1;
b ifnull(t2.b,"this is null")
NULL this is null
insert into t1 values(10,null);
select t2.b, ifnull(t2.b,"this is null") from t1 as t2 left join t1 as t3 on
t2.b=t3.a order by 1;
b ifnull(t2.b,"this is null")
NULL this is null
NULL this is null
drop table t1;
create table t1 (a varchar(10) not null) engine = MEMORY;
create table t2 (b varchar(10) not null unique) engine=MyISAM;
select t1.a from t1,t2 where t1.a=t2.b;
a
drop table t1,t2;
create table t1 (a int not null, b int, primary key (a)) engine = MyISAM;
create table t2 (a int not null, b int, primary key (a)) engine = MyISAM;
insert into t1 values (10, 20);
insert into t2 values (10, 20);
update t1, t2 set t1.b = 150, t2.b = t1.b where t2.a = t1.a and t1.a = 10;
drop table t1,t2;
CREATE TABLE t1 (a int not null primary key, b int not null, unique (b)) engine=MyISAM;
INSERT INTO t1 values (1,1),(2,2),(3,3),(4,4),(5,5),(6,6),(7,7),(8,8),(9,9);
UPDATE t1 set a=a+100 where b between 2and3and a < 1000;
SELECT * from t1;
a b 11 1022 1033 44 55 66 77 88 99
drop table t1;
CREATE TABLE t1 (a int not null primary key, b int not null, key (b)) engine=MyISAM;
CREATE TABLE t2 (a int not null primary key, b int not null, key (b)) engine=MyISAM;
INSERT INTO t1 values (1,1),(2,2),(3,3),(4,4),(5,5),(6,6),(7,7),(8,8),(9,9),(10,10),(11,11),(12,12);
INSERT INTO t2 values (1,1),(2,2),(3,3),(4,4),(5,5),(6,6),(7,7),(8,8),(9,9);
update t1,t2 set t1.a=t1.a+100;
select * from t1;
a b 1011 1022 1033 1044 1055 1066 1077 1088 1099 11010 11111 11212
update t1,t2 set t1.a=t1.a+100 where t1.a=101;
select * from t1;
a b 2011 1022 1033 1044 1055 1066 1077 1088 1099 11010 11111 11212
update t1,t2 set t1.b=t1.b+10 where t1.b=2;
select * from t1;
a b 2011 10212 1033 1044 1055 1066 1077 1088 1099 11010 11111 11212
update t1,t2 set t1.b=t1.b+2,t2.b=t1.b+10 where t1.b between 3and5and t1.a=t2.a+100;
select * from t1;
a b 2011 10212 1035 1046 1057 1066 1077 1088 1099 11010 11111 11212
select * from t2;
a b 11 22 313 414 515 66 77 88 99
drop table t1,t2;
CREATE TABLE t2 ( NEXT_T BIGINT NOT NULL PRIMARY KEY) ENGINE=MEMORY;
CREATE TABLE t1 ( B_ID INTEGER NOT NULL PRIMARY KEY) ENGINE=MyISAM; SET AUTOCOMMIT=0;
INSERT INTO t1 ( B_ID ) VALUES ( 1 );
INSERT INTO t2 ( NEXT_T ) VALUES ( 1 );
ROLLBACK;
Warnings:
Warning 1196 Some non-transactional changed tables couldn't be rolled back
SELECT * FROM t1;
B_ID 1
drop table t1,t2;
create table t1 ( pk int primary key, parent int not null, child int not null, index (parent) ) engine = MyISAM;
insert into t1 values (1,0,4), (2,1,3), (3,2,1), (4,1,2);
select distinct parent,child from t1 order by parent;
parent child 04 12 13 21
drop table t1;
create table t1 (a int not null auto_increment primary key, b int, c int, key(c)) engine=MyISAM;
create table t2 (a int not null auto_increment primary key, b int) ENGINE = MEMORY;
insert into t1 (b) values (null),(null),(null),(null),(null),(null),(null);
insert into t2 (a) select b from t1;
insert into t1 (b) select b from t2;
insert into t2 (a) select b from t1;
insert into t1 (a) select b from t2;
insert into t2 (a) select b from t1;
insert into t1 (a) select b from t2;
insert into t2 (a) select b from t1;
insert into t1 (a) select b from t2;
insert into t2 (a) select b from t1;
insert into t1 (a) select b from t2;
insert into t2 (a) select b from t1;
insert into t1 (a) select b from t2;
insert into t2 (a) select b from t1;
insert into t1 (a) select b from t2;
insert into t2 (a) select b from t1;
insert into t1 (a) select b from t2;
insert into t2 (a) select b from t1;
insert into t1 (a) select b from t2;
select count(*) from t1;
count(*) 29267
explain select * from t1 where c between 1and2500;
id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 range c c 5 NULL # Using index condition
update t1 set c=a;
explain select * from t1 where c between 1and2500;
id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 range c c 5 NULL # Using index condition
drop table t1,t2;
create table t1 (id int primary key auto_increment, fk int, index index_fk (fk)) engine=MyISAM;
insert into t1 (id) values (null),(null),(null),(null),(null);
update t1 set fk=69 where fk is null order by id limit 1;
SELECT * from t1;
id fk 169 2 NULL 3 NULL 4 NULL 5 NULL
drop table t1;
create table t1 (a int not null, b int not null, key (a)) engine=MyISAM;
insert into t1 values (1,1),(1,2),(1,3),(3,1),(3,2),(3,3),(3,1),(3,2),(3,3),(2,1),(2,2),(2,3); SET @tmp=0;
update t1 set b=(@tmp:=@tmp+1) order by a;
update t1 set b=99 where a=1 order by b asc limit 1;
update t1 set b=100 where a=1 order by b desc limit 2;
update t1 set a=a+10+b where a=1 order by b;
select * from t1 order by a,b;
a b 24 25 26 37 38 39 310 311 312 132 111100 111100
drop table t1;
create table t1 ( c char(8) not null ) engine=MyISAM;
insert into t1 values ('0'),('1'),('2'),('3'),('4'),('5'),('6'),('7'),('8'),('9');
insert into t1 values ('A'),('B'),('C'),('D'),('E'),('F');
alter table t1 add b char(8) not null;
alter table t1 add a char(8) not null;
alter table t1 add primary key (a,b,c);
update t1 set a=c, b=c;
create table t2 (c char(8) not null, b char(8) not null, a char(8) not null, primary key(a,b,c)) engine=MyISAM;
insert into t2 select * from t1;
delete t1,t2 from t2,t1 where t1.a<'B'and t2.b=t1.b;
drop table t1,t2; SET AUTOCOMMIT=1;
create table t1 (a integer auto_increment primary key) engine=MyISAM;
insert into t1 (a) values (NULL),(NULL);
truncate table t1;
insert into t1 (a) values (NULL),(NULL);
SELECT * from t1;
a 1 2
drop table t1;
CREATE TABLE t1 (col1 int(1))ENGINE=MyISAM;
CREATE TABLE t2 (col1 int(1),stamp TIMESTAMP,INDEX stamp_idx
(stamp))ENGINE=MyISAM;
insert into t1 values (1),(2),(3);
insert into t2 values (1, 20020204130000),(2, 20020204130000),(4,20020204310000 ),(5,20020204230000);
Warnings:
Warning 1265 Data truncated for column 'stamp' at row 3
SELECT col1 FROM t1 UNION SELECT col1 FROM t2 WHERE stamp < '20020204120000' GROUP BY col1;
col1 1 2 3 4
drop table t1,t2;
CREATE TABLE t1 (
`id` int(10) unsigned NOT NULL auto_increment,
`id_object` int(10) unsigned default '0',
`id_version` int(10) unsigned NOT NULL default '1',
`label` varchar(100) NOT NULL default '',
`description` text,
PRIMARY KEY (`id`),
KEY `id_object` (`id_object`),
KEY `id_version` (`id_version`)
) ENGINE=MyISAM;
INSERT INTO t1 VALUES("6", "3382", "9", "Test", NULL), ("7", "102", "5", "Le Pekin (Test)", NULL),("584", "1794", "4", "Test de resto", NULL),("837", "1822", "6", "Test 3", NULL),("1119", "3524", "1", "Societe Test", NULL),("1122", "3525", "1", "Fournisseur Test", NULL);
CREATE TABLE t2 (
`id` int(10) unsigned NOT NULL auto_increment,
`id_version` int(10) unsigned NOT NULL default '1',
PRIMARY KEY (`id`),
KEY `id_version` (`id_version`)
) ENGINE=MyISAM;
INSERT INTO t2 VALUES("3524", "1"),("3525", "1"),("1794", "4"),("102", "5"),("1822", "6"),("3382", "9");
SELECT t2.id, t1.`label` FROM t2 INNER JOIN
(SELECT t1.id_object as id_object FROM t1 WHERE t1.`label` LIKE '%test%') AS lbl
ON (t2.id = lbl.id_object) INNER JOIN t1 ON (t2.id = t1.id_object);
id label 3382 Test 102 Le Pekin (Test) 1794 Test de resto 1822 Test 3 3524 Societe Test 3525 Fournisseur Test
drop table t1,t2;
create table t1 (a int, b varchar(200), c text not null) checksum=1 engine=MyISAM;
create table t2 (a int, b varchar(200), c text not null) checksum=0 engine=MyISAM;
create table t3 (a int, b varchar(200), c varchar(200) not null) checksum=1 engine=MEMORY;
create table t4 (a int, b varchar(200), c varchar(200) not null) checksum=0 engine=MEMORY;
create table t5 (a int, b varchar(200), c text not null) checksum=1 engine=MyISAM;
create table t6 (a int, b varchar(200), c text not null) checksum=0 engine=MyISAM;
insert t1 values (1, "aaa", "bbb"), (NULL, "", "ccccc"), (0, NULL, "");
insert t2 select * from t1;
insert t3 select * from t1;
insert t4 select * from t1;
insert t5 select * from t1;
insert t6 select * from t1;
checksum table t1, t2, t3, t4, t5, t6, t7 quick;
Table Checksum
test.t1 3442722830
test.t2 NULL
test.t3 NULL
test.t4 NULL
test.t5 3442722830
test.t6 NULL
test.t7 NULL
Warnings: Error1146 Table 'test.t7' doesn't exist
checksum table t1, t2, t3, t4, t5, t6, t7;
Table Checksum
test.t1 3442722830
test.t2 3442722830
test.t3 3442722830
test.t4 3442722830
test.t5 3442722830
test.t6 3442722830
test.t7 NULL
Warnings: Error1146 Table 'test.t7' doesn't exist
checksum table t1, t2, t3, t4, t5, t6, t7 extended;
Table Checksum
test.t1 3442722830
test.t2 3442722830
test.t3 3442722830
test.t4 3442722830
test.t5 3442722830
test.t6 3442722830
test.t7 NULL
Warnings: Error1146 Table 'test.t7' doesn't exist
drop table t1,t2,t3, t4, t5, t6;
create table t1 (id int, name char(10) not null, name2 char(10) not null) engine=MyISAM;
insert into t1 values(1,'first','fff'),(2,'second','sss'),(3,'third','ttt');
select trim(name2) from t1 union all select trim(name) from t1 union all select trim(id) from t1;
trim(name2)
fff
sss
ttt
first
second
third 1 2 3
drop table t1;
create table t1 (a int) engine=MyISAM;
create table t2 like t1;
show create table t2;
Table Create Table
t2 CREATE TABLE `t2` (
`a` int(11) DEFAULT NULL
) ENGINE=MyISAM DEFAULT CHARSET=latin1 COLLATE=latin1_swedish_ci
drop table t1,t2;
flush status;
show status like "binlog_cache_use";
Variable_name Value
Binlog_cache_use 0
show status like "binlog_cache_disk_use";
Variable_name Value
Binlog_cache_disk_use 0
create table t1 (a int) engine=MyISAM;
show status like "binlog_cache_use";
Variable_name Value
Binlog_cache_use 0
show status like "binlog_cache_disk_use";
Variable_name Value
Binlog_cache_disk_use 0
begin;
delete from t1;
commit;
show status like "binlog_cache_use";
Variable_name Value
Binlog_cache_use 0
show status like "binlog_cache_disk_use";
Variable_name Value
Binlog_cache_disk_use 0
drop table t1;
create table t1 (c char(10), index (c,c)) engine=MyISAM; ERROR42S21: Duplicate column name 'c'
create table t1 (c1 char(10), c2 char(10), index (c1,c2,c1)) engine=MyISAM; ERROR42S21: Duplicate column name 'c1'
create table t1 (c1 char(10), c2 char(10), index (c1,c1,c2)) engine=MyISAM; ERROR42S21: Duplicate column name 'c1'
create table t1 (c1 char(10), c2 char(10), index (c2,c1,c1)) engine=MyISAM; ERROR42S21: Duplicate column name 'c1'
create table t1 (c1 char(10), c2 char(10)) engine=MyISAM;
alter table t1 add key (c1,c1); ERROR42S21: Duplicate column name 'c1'
alter table t1 add key (c2,c1,c1); ERROR42S21: Duplicate column name 'c1'
alter table t1 add key (c1,c2,c1); ERROR42S21: Duplicate column name 'c1'
alter table t1 add key (c1,c1,c2); ERROR42S21: Duplicate column name 'c1'
drop table t1;
create table t1(a int(1) , b int(1)) engine=MyISAM;
insert into t1 values ('1111', '3333');
select distinct concat(a, b) from t1;
concat(a, b) 11113333
drop table t1;
create temporary table t1 (a int) engine=MyISAM;
insert into t1 values (4711);
truncate t1;
insert into t1 values (42);
select * from t1;
a 42
drop table t1;
create table t1 (a int) engine=MyISAM;
insert into t1 values (4711);
truncate t1;
insert into t1 values (42);
select * from t1;
a 42
drop table t1;
create table t1 (a int not null, b int not null, c blob not null, d int not null, e int, primary key (a,b,c(255),d)) engine=MyISAM;
insert into t1 values (2,2,"b",2,2),(1,1,"a",1,1),(3,3,"ab",3,3);
select * from t1 order by a,b,c,d;
a b c d e 11 a 11 22 b 22 33 ab 33
explain select * from t1 order by a,b,c,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
drop table t1;
create table t1 (a char(1), b char(1), key(a, b)) engine=MyISAM;
insert into t1 values ('8', '6'), ('4', '7');
select min(a) from t1; min(a) 4
select min(b) from t1 where a='8'; min(b) 6
drop table t1;
create table t1 (x bigint unsigned not null primary key) engine=MyISAM;
insert into t1(x) values (0xfffffffffffffff0),(0xfffffffffffffff1);
select * from t1;
x 18446744073709551600 18446744073709551601
select count(*) from t1 where x>0;
count(*) 2
select count(*) from t1 where x=0;
count(*) 0
select count(*) from t1 where x<0;
count(*) 0
select count(*) from t1 where x < -16;
count(*) 0
select count(*) from t1 where x = -16;
count(*) 0
explain select count(*) from t1 where x > -16;
id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 index PRIMARY PRIMARY 8 NULL 2 Using where; Using index
select count(*) from t1 where x > -16;
count(*) 2
select * from t1 where x > -16;
x 18446744073709551600 18446744073709551601
select count(*) from t1 where x = 18446744073709551601;
count(*) 1
drop table t1; set default_storage_engine=MyISAM;
drop table if exists t1,t2,t3;
--- Testing varchar ---
--- Testing varchar ---
create table t1 (v varchar(10), c char(10), t text);
insert into t1 values('+ ', '+ ', '+ '); set @a=repeat(' ',20);
insert into t1 values (concat('+',@a),concat('+',@a),concat('+',@a));
Warnings:
Note 1265 Data truncated for column 'v' at row 1
select concat('*',v,'*',c,'*',t,'*') from t1;
concat('*',v,'*',c,'*',t,'*')
*+ *+*+ *
*+ *+*+ *
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`v` varchar(10) DEFAULT NULL,
`c` char(10) DEFAULT NULL,
`t` text DEFAULT NULL
) ENGINE=MyISAM DEFAULT CHARSET=latin1 COLLATE=latin1_swedish_ci
create table t2 like t1;
show create table t2;
Table Create Table
t2 CREATE TABLE `t2` (
`v` varchar(10) DEFAULT NULL,
`c` char(10) DEFAULT NULL,
`t` text DEFAULT NULL
) ENGINE=MyISAM DEFAULT CHARSET=latin1 COLLATE=latin1_swedish_ci
create table t3 select * from t1;
show create table t3;
Table Create Table
t3 CREATE TABLE `t3` (
`v` varchar(10) DEFAULT NULL,
`c` char(10) DEFAULT NULL,
`t` text DEFAULT NULL
) ENGINE=MyISAM DEFAULT CHARSET=latin1 COLLATE=latin1_swedish_ci
alter table t1 modify c varchar(10);
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`v` varchar(10) DEFAULT NULL,
`c` varchar(10) DEFAULT NULL,
`t` text DEFAULT NULL
) ENGINE=MyISAM DEFAULT CHARSET=latin1 COLLATE=latin1_swedish_ci
alter table t1 modify v char(10);
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`v` char(10) DEFAULT NULL,
`c` varchar(10) DEFAULT NULL,
`t` text DEFAULT NULL
) ENGINE=MyISAM DEFAULT CHARSET=latin1 COLLATE=latin1_swedish_ci
alter table t1 modify t varchar(10);
Warnings:
Note 1265 Data truncated for column 't' at row 2
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`v` char(10) DEFAULT NULL,
`c` varchar(10) DEFAULT NULL,
`t` varchar(10) DEFAULT NULL
) ENGINE=MyISAM DEFAULT CHARSET=latin1 COLLATE=latin1_swedish_ci
select concat('*',v,'*',c,'*',t,'*') from t1;
concat('*',v,'*',c,'*',t,'*')
*+*+*+ *
*+*+*+ *
drop table t1,t2,t3;
create table t1 (v varchar(10), c char(10), t text, key(v), key(c), key(t(10)));
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`v` varchar(10) DEFAULT NULL,
`c` char(10) DEFAULT NULL,
`t` text DEFAULT NULL,
KEY `v` (`v`),
KEY `c` (`c`),
KEY `t` (`t`(10))
) ENGINE=MyISAM DEFAULT CHARSET=latin1 COLLATE=latin1_swedish_ci
select count(*) from t1;
count(*) 270
insert into t1 values(concat('a',char(1)),concat('a',char(1)),concat('a',char(1)));
select count(*) from t1 where v='a';
count(*) 10
select count(*) from t1 where c='a';
count(*) 10
select count(*) from t1 where t='a';
count(*) 10
select count(*) from t1 where v='a ';
count(*) 10
select count(*) from t1 where c='a ';
count(*) 10
select count(*) from t1 where t='a ';
count(*) 10
select count(*) from t1 where v between 'a'and'a ';
count(*) 10
select count(*) from t1 where v between 'a'and'a 'and v between 'a 'and'b\n';
count(*) 10
select count(*) from t1 where v like 'a%';
count(*) 11
select count(*) from t1 where c like 'a%';
count(*) 11
select count(*) from t1 where t like 'a%';
count(*) 11
select count(*) from t1 where v like 'a %';
count(*) 9
explain select count(*) from t1 where v='a ';
id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 ref v v 13 const # Using where; Using index
explain select count(*) from t1 where c='a ';
id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 ref c c 11 const # Using where; Using index
explain select count(*) from t1 where t='a ';
id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 ref t t 13 const # Using where
explain select count(*) from t1 where v like 'a%';
id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 range v v 13 NULL # Using where; Using index
explain select count(*) from t1 where v between 'a'and'a ';
id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 ref v v 13 const # Using where; Using index
explain select count(*) from t1 where v between 'a'and'a 'and v between 'a 'and'b\n';
id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 ref v v 13 const # Using where; Using index
alter table t1 add unique(v); ERROR23000: Duplicate entry 'a ' for key 'v_2'
alter table t1 add key(v);
Warnings:
Note 1831 Duplicate index `v_2`. This is deprecated and will be disallowed in a future release
select concat('*',v,'*',c,'*',t,'*') as qq from t1 where v='a';
qq
*a*a*a*
*a *a*a *
*a *a*a *
*a *a*a *
*a *a*a *
*a *a*a *
*a *a*a *
*a *a*a *
*a *a*a *
*a *a*a *
explain select * from t1 where v='a';
id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 ref v,v_2 # 13 const # #
select v,count(*) from t1 group by v limit 10;
v count(*)
a 1
a 10
b 10
c 10
d 10
e 10
f 10
g 10
h 10
i 10
select v,count(t) from t1 group by v limit 10;
v count(t)
a 1
a 10
b 10
c 10
d 10
e 10
f 10
g 10
h 10
i 10
select v,count(c) from t1 group by v limit 10;
v count(c)
a 1
a 10
b 10
c 10
d 10
e 10
f 10
g 10
h 10
i 10
select sql_big_result v,count(t) from t1 group by v limit 10;
v count(t)
a 1
a 10
b 10
c 10
d 10
e 10
f 10
g 10
h 10
i 10
select sql_big_result v,count(c) from t1 group by v limit 10;
v count(c)
a 1
a 10
b 10
c 10
d 10
e 10
f 10
g 10
h 10
i 10
select c,count(*) from t1 group by c limit 10;
c count(*)
a 1
a 10
b 10
c 10
d 10
e 10
f 10
g 10
h 10
i 10
select c,count(t) from t1 group by c limit 10;
c count(t)
a 1
a 10
b 10
c 10
d 10
e 10
f 10
g 10
h 10
i 10
select sql_big_result c,count(t) from t1 group by c limit 10;
c count(t)
a 1
a 10
b 10
c 10
d 10
e 10
f 10
g 10
h 10
i 10
select t,count(*) from t1 group by t limit 10;
t count(*)
a 1
a 10
b 10
c 10
d 10
e 10
f 10
g 10
h 10
i 10
select t,count(t) from t1 group by t limit 10;
t count(t)
a 1
a 10
b 10
c 10
d 10
e 10
f 10
g 10
h 10
i 10
select sql_big_result t,count(t) from t1 group by t limit 10;
t count(t)
a 1
a 10
b 10
c 10
d 10
e 10
f 10
g 10
h 10
i 10
alter table t1 modify v varchar(300), drop key v, drop key v_2, add key v (v);
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`v` varchar(300) DEFAULT NULL,
`c` char(10) DEFAULT NULL,
`t` text DEFAULT NULL,
KEY `c` (`c`),
KEY `t` (`t`(10)),
KEY `v` (`v`)
) ENGINE=MyISAM DEFAULT CHARSET=latin1 COLLATE=latin1_swedish_ci
select count(*) from t1 where v='a';
count(*) 10
select count(*) from t1 where v='a ';
count(*) 10
select count(*) from t1 where v between 'a'and'a ';
count(*) 10
select count(*) from t1 where v between 'a'and'a 'and v between 'a 'and'b\n';
count(*) 10
select count(*) from t1 where v like 'a%';
count(*) 11
select count(*) from t1 where v like 'a %';
count(*) 9
explain select count(*) from t1 where v='a ';
id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 ref v v 303 const # Using where; Using index
explain select count(*) from t1 where v like 'a%';
id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 range v v 303 NULL # Using where; Using index
explain select count(*) from t1 where v between 'a'and'a ';
id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 ref v v 303 const # Using where; Using index
explain select count(*) from t1 where v between 'a'and'a 'and v between 'a 'and'b\n';
id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 ref v v 303 const # Using where; Using index
explain select * from t1 where v='a';
id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 ref v v 303 const # #
select v,count(*) from t1 group by v limit 10;
v count(*)
a 1
a 10
b 10
c 10
d 10
e 10
f 10
g 10
h 10
i 10
select v,count(t) from t1 group by v limit 10;
v count(t)
a 1
a 10
b 10
c 10
d 10
e 10
f 10
g 10
h 10
i 10
select sql_big_result v,count(t) from t1 group by v limit 10;
v count(t)
a 1
a 10
b 10
c 10
d 10
e 10
f 10
g 10
h 10
i 10
alter table t1 drop key v, add key v (v(30));
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`v` varchar(300) DEFAULT NULL,
`c` char(10) DEFAULT NULL,
`t` text DEFAULT NULL,
KEY `c` (`c`),
KEY `t` (`t`(10)),
KEY `v` (`v`(30))
) ENGINE=MyISAM DEFAULT CHARSET=latin1 COLLATE=latin1_swedish_ci
select count(*) from t1 where v='a';
count(*) 10
select count(*) from t1 where v='a ';
count(*) 10
select count(*) from t1 where v between 'a'and'a ';
count(*) 10
select count(*) from t1 where v between 'a'and'a 'and v between 'a 'and'b\n';
count(*) 10
select count(*) from t1 where v like 'a%';
count(*) 11
select count(*) from t1 where v like 'a %';
count(*) 9
explain select count(*) from t1 where v='a ';
id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 ref v v 33 const # Using where
explain select count(*) from t1 where v like 'a%';
id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 range v v 33 NULL # Using where
explain select count(*) from t1 where v between 'a'and'a ';
id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 ref v v 33 const # Using where
explain select count(*) from t1 where v between 'a'and'a 'and v between 'a 'and'b\n';
id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 ref v v 33 const # Using where
explain select * from t1 where v='a';
id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 ref v v 33 const # #
select v,count(*) from t1 group by v limit 10;
v count(*)
a 1
a 10
b 10
c 10
d 10
e 10
f 10
g 10
h 10
i 10
select v,count(t) from t1 group by v limit 10;
v count(t)
a 1
a 10
b 10
c 10
d 10
e 10
f 10
g 10
h 10
i 10
select sql_big_result v,count(t) from t1 group by v limit 10;
v count(t)
a 1
a 10
b 10
c 10
d 10
e 10
f 10
g 10
h 10
i 10
alter table t1 modify v varchar(600), drop key v, add key v (v);
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`v` varchar(600) DEFAULT NULL,
`c` char(10) DEFAULT NULL,
`t` text DEFAULT NULL,
KEY `c` (`c`),
KEY `t` (`t`(10)),
KEY `v` (`v`)
) ENGINE=MyISAM DEFAULT CHARSET=latin1 COLLATE=latin1_swedish_ci
select v,count(*) from t1 group by v limit 10;
v count(*)
a 1
a 10
b 10
c 10
d 10
e 10
f 10
g 10
h 10
i 10
select v,count(t) from t1 group by v limit 10;
v count(t)
a 1
a 10
b 10
c 10
d 10
e 10
f 10
g 10
h 10
i 10
select sql_big_result v,count(t) from t1 group by v limit 10;
v count(t)
a 1
a 10
b 10
c 10
d 10
e 10
f 10
g 10
h 10
i 10
drop table t1;
create table t1 (a char(10), unique (a));
insert into t1 values ('a ');
insert into t1 values ('a '); ERROR23000: Duplicate entry 'a' for key 'a'
alter table t1 modify a varchar(10);
insert into t1 values ('a '),('a '),('a '),('a '); ERROR23000: Duplicate entry 'a ' for key 'a'
insert into t1 values ('a '); ERROR23000: Duplicate entry 'a ' for key 'a'
insert into t1 values ('a '); ERROR23000: Duplicate entry 'a ' for key 'a'
insert into t1 values ('a '); ERROR23000: Duplicate entry 'a ' for key 'a'
update t1 set a='a ' where a like 'a%';
select concat(a,'.') from t1;
concat(a,'.')
a .
update t1 set a='abc ' where a like 'a ';
select concat(a,'.') from t1;
concat(a,'.')
a .
update t1 set a='a ' where a like 'a %';
select concat(a,'.') from t1;
concat(a,'.')
a .
update t1 set a='a ' where a like 'a ';
select concat(a,'.') from t1;
concat(a,'.')
a .
drop table t1;
create table t1 (v varchar(10), c char(10), t text, key(v(5)), key(c(5)), key(t(5)));
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`v` varchar(10) DEFAULT NULL,
`c` char(10) DEFAULT NULL,
`t` text DEFAULT NULL,
KEY `v` (`v`(5)),
KEY `c` (`c`(5)),
KEY `t` (`t`(5))
) ENGINE=MyISAM DEFAULT CHARSET=latin1 COLLATE=latin1_swedish_ci
drop table t1;
create table t1 (v char(10) character set utf8);
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`v` char(10) CHARACTER SET utf8mb4 COLLATE utf8mb4_uca1400_ai_ci DEFAULT NULL
) ENGINE=MyISAM DEFAULT CHARSET=latin1 COLLATE=latin1_swedish_ci
drop table t1;
create table t1 (v varchar(10), c char(10)) row_format=fixed;
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`v` varchar(10) DEFAULT NULL,
`c` char(10) DEFAULT NULL
) ENGINE=MyISAM DEFAULT CHARSET=latin1 COLLATE=latin1_swedish_ci ROW_FORMAT=FIXED
insert into t1 values('a','a'),('a ','a ');
select concat('*',v,'*',c,'*') from t1;
concat('*',v,'*',c,'*')
*a*a*
*a *a*
drop table t1;
create table t1 (v varchar(65530), key(v(10)));
insert into t1 values(repeat('a',65530));
select length(v) from t1 where v=repeat('a',65530);
length(v) 65530
drop table t1;
create table t1(a int, b varchar(12), key ba(b, a));
insert into t1 values (1, 'A'), (20, NULL);
explain select * from t1 where a=20and b is null;
id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 ref ba ba 20 const,const 1 Using where; Using index
select * from t1 where a=20and b is null;
a b 20 NULL
drop table t1;
create table t1 (v varchar(65530), key(v));
Warnings:
Note 1071 Specified key was too long; max key length is 1000 bytes
drop table t1; SET STATEMENT sql_mode = 'NO_ENGINE_SUBSTITUTION' FOR
create table t1 (v varchar(65536));
Warnings:
Note 1246 Converting column 'v' from VARCHAR to TEXT
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`v` mediumtext DEFAULT NULL
) ENGINE=MyISAM DEFAULT CHARSET=latin1 COLLATE=latin1_swedish_ci
drop table t1; SET STATEMENT sql_mode = 'NO_ENGINE_SUBSTITUTION' FOR
create table t1 (v varchar(65530) character set utf8);
Warnings:
Note 1246 Converting column 'v' from VARCHAR to TEXT
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`v` mediumtext CHARACTER SET utf8mb4 COLLATE utf8mb4_uca1400_ai_ci DEFAULT NULL
) ENGINE=MyISAM DEFAULT CHARSET=latin1 COLLATE=latin1_swedish_ci
drop table t1; set default_storage_engine=MEMORY;
create table t1 (v varchar(16384)) engine=MyISAM;
drop table t1;
create table t1 (a char(1), b char(1), key(a, b)) engine=MyISAM;
insert into t1 values ('8', '6'), ('4', '7');
select min(a) from t1; min(a) 4
select min(b) from t1 where a='8'; min(b) 6
drop table t1;
CREATE TABLE t1 ( `a` int(11) NOT NULL auto_increment, `b` int(11) default NULL,PRIMARY KEY (`a`),UNIQUE KEY `b` (`b`)) ENGINE=MyISAM;
insert into t1 (b) values (1); replace into t1 (b) values (2), (1), (3);
select * from t1;
a b 31 22 43
truncate table t1;
insert into t1 (b) values (1); replace into t1 (b) values (2); replace into t1 (b) values (1); replace into t1 (b) values (3);
select * from t1;
a b 31 22 43
drop table t1;
create table t1 (rowid int not null auto_increment, val int not null,primary
key (rowid), unique(val)) engine=MyISAM; replace into t1 (val) values ('1'),('2'); replace into t1 (val) values ('1'),('2');
insert into t1 (val) values ('1'),('2'); ERROR23000: Duplicate entry '1' for key 'val'
select * from t1;
rowid val 31 42
drop table t1;
CREATE TABLE t1 (GRADE DECIMAL(4) NOT NULL, PRIMARY KEY (GRADE)) ENGINE=MyISAM;
INSERT INTO t1 (GRADE) VALUES (151),(252),(343);
SELECT GRADE FROM t1 WHERE GRADE > 160AND GRADE < 300;
GRADE 252
SELECT GRADE FROM t1 WHERE GRADE= 151;
GRADE 151
DROP TABLE t1;
create table t1 (f1 varchar(10), f2 varchar(10), primary key (f1,f2)) engine=MyISAM;
create table t2 (f3 varchar(10), f4 varchar(10), key (f4)) engine=MyISAM;
insert into t2 values ('aa','cc');
insert into t1 values ('aa','bb'),('aa','cc');
delete t1 from t1,t2 where f1=f3 and f4='cc';
select * from t1;
f1 f2
drop table t1,t2;
connect a,localhost,root,,;
connect b,localhost,root,,;
connection a;
create table t1(a int not null, b int, c int, d int, primary key(a)) engine=MyISAM;
insert into t1(a) values (1),(2),(3);
commit;
connection b; set autocommit = 0;
update t1 set b = 5 where a = 2;
commit;
connection a;
create trigger t1t before insert on t1 for each row begin set NEW.b = NEW.a * 10 + 5, NEW.c = NEW.a / 10; end | set autocommit = 0;
connection a;
insert into t1(a) values (10),(20),(30),(40),(50),(60),(70),(80),(90),(100),
(11),(21),(31),(41),(51),(61),(71),(81),(91),(101),
(12),(22),(32),(42),(52),(62),(72),(82),(92),(102),
(13),(23),(33),(43),(53),(63),(73),(83),(93),(103),
(14),(24),(34),(44),(54),(64),(74),(84),(94),(104);
connection b;
commit;
connection a;
commit;
drop trigger t1t;
drop table t1;
disconnect a;
disconnect b;
connect a,localhost,root,,;
connect b,localhost,root,,;
connection a;
create table t1(a int not null, b int, c int, d int, primary key(a)) engine=MyISAM;
create table t2(a int not null, b int, c int, d int, primary key(a)) engine=MyISAM;
create table t3(a int not null, b int, c int, d int, primary key(a)) engine=MyISAM;
create table t4(a int not null, b int, c int, d int, primary key(a)) engine=MyISAM;
create table t5(a int not null, b int, c int, d int, primary key(a)) engine=MyISAM;
insert into t1(a) values (1),(2),(3);
insert into t2(a) values (1),(2),(3);
insert into t3(a) values (1),(2),(3);
insert into t4(a) values (1),(2),(3);
insert into t3(a) values (5),(7),(8);
insert into t4(a) values (5),(7),(8);
insert into t5(a) values (1),(2),(3),(4),(5),(6),(7),(8),(9),(10),(11),(12);
create trigger t1t before insert on t1 for each row begin
INSERT INTO t2 SET a = NEW.a;
end |
create trigger t2t before insert on t2 for each row begin
DELETE FROM t3 WHERE a = NEW.a;
end |
create trigger t3t before delete on t3 for each row begin
UPDATE t4 SET b = b + 1 WHERE a = OLD.a;
end |
create trigger t4t before update on t4 for each row begin
UPDATE t5 SET b = b + 1 where a = NEW.a;
end |
commit; set autocommit = 0;
update t1 set b = b + 5 where a = 1;
update t2 set b = b + 5 where a = 1;
update t3 set b = b + 5 where a = 1;
update t4 set b = b + 5 where a = 1;
insert into t5(a) values(20);
commit;
connection b; set autocommit = 0;
insert into t1(a) values(7);
insert into t2(a) values(8);
delete from t2 where a = 3;
update t4 set b = b + 1 where a = 3;
commit;
drop trigger t1t;
drop trigger t2t;
drop trigger t3t;
drop trigger t4t;
drop table t1, t2, t3, t4, t5;
connection default;
disconnect a;
disconnect b;
create table t1(a date) engine=MyISAM;
create table t2(a date, key(a)) engine=MyISAM;
insert into t1 values('2005-10-01');
insert into t2 values('2005-10-01');
select * from t1, t2
where t2.a between t1.a - interval 2 day and t1.a + interval 2 day;
a a 2005-10-012005-10-01
drop table t1, t2;
create table t1 (id int not null, f_id int not null, f int not null,
primary key(f_id, id)) engine=MyISAM;
create table t2 (id int not null,s_id int not null,s varchar(200),
primary key(id)) engine=MyISAM;
INSERT INTO t1 VALUES (8, 1, 3);
INSERT INTO t1 VALUES (1, 2, 1);
INSERT INTO t2 VALUES (1, 0, '');
INSERT INTO t2 VALUES (8, 1, '');
commit;
DELETE ml.* FROM t1 AS ml LEFT JOIN t2 AS mm ON (mm.id=ml.id)
WHERE mm.id IS NULL;
select ml.* from t1 as ml left join t2 as mm on (mm.id=ml.id)
where mm.id is null lock in share mode;
id f_id f
drop table t1,t2;
connect a,localhost,root,,;
connect b,localhost,root,,;
connection a;
create table t1(a int not null, b int, primary key(a)) engine=MyISAM;
insert into t1 values(1,1),(2,2),(3,1),(4,2),(5,1),(6,2),(7,3);
commit; set autocommit = 0; SET SESSION TRANSACTION ISOLATION LEVEL READ COMMITTED;
update t1 set b = 5 where b = 1;
connection b; set autocommit = 0; SET SESSION TRANSACTION ISOLATION LEVEL READ COMMITTED;
select * from t1 where a = 7and b = 3 for update;
a b 73
connection a;
commit;
connection b;
commit;
drop table t1;
connection default;
disconnect a;
disconnect b;
CREATE TABLE t1 ( a int ) ENGINE=MyISAM;
BEGIN;
INSERT INTO t1 VALUES (1);
OPTIMIZE TABLE t1;
Table Op Msg_type Msg_text
test.t1 optimize status OK
DROP TABLE t1;
ALTER DATABASE test CHARACTER SET utf8mb4 COLLATE utf8mb4_uca1400_ai_ci;
Messung V0.5 in Prozent
¤ Dauer der Verarbeitung: 0.53 Sekunden
(vorverarbeitet am 2026-10-08)
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