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|
drop table if exists 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)) type=innodb;
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
1 1 Tim
2 1 Monty
3 2 David
4 2 Erik
5 3 Sasha
6 3 Jeremy
7 4 Matt
update ignore t1 set id = 8, name = 'Sinisa' where id < 3;
select id, code, name from t1 order by id;
id code name
2 1 Monty
3 2 David
4 2 Erik
5 3 Sasha
6 3 Jeremy
7 4 Matt
8 1 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
3 2 David
4 2 Erik
5 3 Sasha
6 3 Jeremy
7 4 Matt
8 1 Sinisa
12 1 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)
) type=innodb;
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
8 102 2
9 102 2
15 102 2
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
1001 100 0
1002 101 1
1003 101 1
1004 101 1
1005 101 1
1006 101 1
1007 101 1
1008 102 2
1009 102 2
1015 102 2
1016 103 2
1017 103 2
1018 103 2
1019 103 2
1020 103 2
1021 104 2
1022 104 2
1024 104 2
1025 105 2
1026 105 2
1027 105 2
1028 105 2
1029 105 2
1030 105 2
1031 106 2
1032 106 2
1033 106 2
1034 106 2
1035 106 2
1036 107 2
1037 107 2
1038 107 2
1040 107 2
1157 100 0
1179 105 2
1183 104 2
1193 105 2
1202 107 2
1203 107 2
update ignore t1 set id=id+1;
select * from t1;
id parent_id level
1001 100 0
1002 101 1
1003 101 1
1004 101 1
1005 101 1
1006 101 1
1007 101 1
1008 102 2
1010 102 2
1015 102 2
1016 103 2
1017 103 2
1018 103 2
1019 103 2
1020 103 2
1021 104 2
1023 104 2
1024 104 2
1025 105 2
1026 105 2
1027 105 2
1028 105 2
1029 105 2
1030 105 2
1031 106 2
1032 106 2
1033 106 2
1034 106 2
1035 106 2
1036 107 2
1037 107 2
1039 107 2
1041 107 2
1158 100 0
1180 105 2
1184 104 2
1194 105 2
1202 107 2
1204 107 2
update ignore t1 set id=1023 where id=1010;
select * from t1 where parent_id=102;
id parent_id level
1008 102 2
1010 102 2
1015 102 2
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 12 Using where; 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 12 Using where; Using index
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 12 Using where
select level,id from t1 where level=1;
level id
1 1002
1 1003
1 1004
1 1005
1 1006
1 1007
select level,id,parent_id from t1 where level=1;
level id parent_id
1 1002 101
1 1003 101
1 1004 101
1 1005 101
1 1006 101
1 1007 101
optimize table t1;
Table Op Msg_type Msg_text
test.t1 optimize error The handler for the table doesn't support optimize
show keys from t1;
Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment
t1 0 PRIMARY 1 id A 87 NULL NULL BTREE
t1 1 parent_id 1 parent_id A 43 NULL NULL BTREE
t1 1 level 1 level A 6 NULL NULL BTREE
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)
) type=innodb;
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
1 1
2 1
drop table t1;
create table t1 (a int) type=innodb;
insert into t1 values (1), (2);
optimize table t1;
Table Op Msg_type Msg_text
test.t1 optimize error The handler for the table doesn't support optimize
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)) type=innodb;
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 error The handler for the table doesn't support analyze
show keys from t1;
Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment
t1 1 skr 1 a A 3 NULL NULL YES BTREE
drop table t1;
create table t1 (a int,b varchar(20),key(a)) type=innodb;
insert into t1 values (1,""), (2,"testing");
select * from t1 where a = 1;
a b
1
drop table t1;
create table t1 (n int not null primary key) type=innodb;
set autocommit=0;
insert into t1 values (4);
rollback;
select n, "after rollback" from t1;
n after rollback
insert into t1 values (4);
commit;
select n, "after commit" from t1;
n after commit
4 after commit
commit;
insert into t1 values (5);
insert into t1 values (4);
Duplicate entry '4' for key 1
commit;
select n, "after commit" from t1;
n after commit
4 after commit
5 after commit
set autocommit=1;
insert into t1 values (6);
insert into t1 values (4);
Duplicate entry '4' for key 1
select n from t1;
n
4
5
6
rollback;
drop table t1;
create table t1 ( id int NOT NULL PRIMARY KEY, nom varchar(64)) type=innodb;
begin;
insert into t1 values(1,'hamdouni');
select id as afterbegin_id,nom as afterbegin_nom from t1;
afterbegin_id afterbegin_nom
1 hamdouni
rollback;
select id as afterrollback_id,nom as afterrollback_nom from t1;
afterrollback_id afterrollback_nom
set autocommit=0;
insert into t1 values(2,'mysql');
select id as afterautocommit0_id,nom as afterautocommit0_nom from t1;
afterautocommit0_id afterautocommit0_nom
2 mysql
rollback;
select id as afterrollback_id,nom as afterrollback_nom from t1;
afterrollback_id afterrollback_nom
set autocommit=1;
drop table t1;
CREATE TABLE t1 (id char(8) not null primary key, val int not null) type=innodb;
insert into t1 values ('pippo', 12);
insert into t1 values ('pippo', 12);
Duplicate entry 'pippo' for key 1
delete from t1;
delete from t1 where id = 'pippo';
select * from t1;
id val
insert into t1 values ('pippo', 12);
set autocommit=0;
delete from t1;
rollback;
select * from t1;
id val
pippo 12
delete from t1;
commit;
select * from t1;
id val
drop table t1;
create table t1 (a integer) type=innodb;
begin;
rename table t1 to t2;
create table t1 (b integer) type=innodb;
insert into t1 values (1);
rollback;
drop table t1;
rename table t2 to t1;
drop table t1;
set autocommit=1;
CREATE TABLE t1 (ID INTEGER NOT NULL PRIMARY KEY, NAME VARCHAR(64)) TYPE=innodb;
INSERT INTO t1 VALUES (1, 'Jochen');
select * from t1;
ID NAME
1 Jochen
drop table t1;
CREATE TABLE t1 ( _userid VARCHAR(60) NOT NULL PRIMARY KEY) TYPE=innodb;
set autocommit=0;
INSERT INTO t1 SET _userid='marc@anyware.co.uk';
COMMIT;
SELECT * FROM t1;
_userid
marc@anyware.co.uk
SELECT _userid FROM t1 WHERE _userid='marc@anyware.co.uk';
_userid
marc@anyware.co.uk
drop table t1;
set autocommit=1;
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)
)type=innodb;
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));
show index from t1;
Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment
t1 0 PRIMARY 1 a A NULL NULL NULL BTREE
t1 0 PRIMARY 2 b A 0 NULL NULL BTREE
t1 0 c 1 c A 0 NULL NULL BTREE
t1 0 b 1 b A 0 NULL NULL BTREE
t1 1 a 1 a A NULL NULL NULL BTREE
t1 1 a_2 1 a A NULL NULL NULL BTREE
drop table t1;
create table t1 (col1 int not null, col2 char(4) not null, primary key(col1));
alter table t1 type=innodb;
insert into t1 values ('1','1'),('5','2'),('2','3'),('3','4'),('4','4');
select * from t1;
col1 col2
1 1
2 3
3 4
4 4
5 2
update t1 set col2='7' where col1='4';
select * from t1;
col1 col2
1 1
2 3
3 4
4 7
5 2
alter table t1 add co3 int not null;
select * from t1;
col1 col2 co3
1 1 0
2 3 0
3 4 0
4 7 0
5 2 0
update t1 set col2='9' where col1='2';
select * from t1;
col1 col2 co3
1 1 0
2 9 0
3 4 0
4 7 0
5 2 0
drop table t1;
create table t1 (a int not null , b int, primary key (a)) type = innodb;
create table t2 (a int not null , b int, primary key (a)) type = myisam;
insert into t1 VALUES (1,3) , (2,3), (3,3);
select * from t1;
a b
1 3
2 3
3 3
insert into t2 select * from t1;
select * from t2;
a b
1 3
2 3
3 3
delete from t1 where b = 3;
select * from t1;
a b
insert into t1 select * from t2;
select * from t1;
a b
1 3
2 3
3 3
select * from t2;
a b
1 3
2 3
3 3
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)
) TYPE=innodb;
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');
Duplicate entry 'test2' for key 2
insert into t1 (ggid,id) values ('this will fail',1);
Duplicate entry '1' for key 1
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;
Duplicate entry 'test2' for key 2
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)
) TYPE=innodb;
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 0 0 0 2000-09-07 23:06:59 2000-09-07 23:06:59 1
user_1 somepassword Y 1 1 1 2000-09-07 23:06:59 2000-09-07 23:06:59 2
user_2 somepassword N 2 2 1.4142135623731 2000-09-07 23:06:59 2000-09-07 23:06:59 3
user_3 somepassword Y 3 3 1.7320508075689 2000-09-07 23:06:59 2000-09-07 23:06:59 4
user_4 somepassword N 4 4 2 2000-09-07 23:06:59 2000-09-07 23:06:59 5
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)
) type=innodb;
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
8 102 2
9 102 2
15 102 2
update t1 set id=id+1000;
update t1 set id=1024 where id=1009;
select * from t1;
id parent_id level
1001 100 0
1003 101 1
1004 101 1
1008 102 2
1024 102 2
1017 103 2
1022 104 2
1024 104 2
1028 105 2
1029 105 2
1030 105 2
1031 106 2
1032 106 2
1033 106 2
1203 107 2
1202 107 2
1020 103 2
1157 100 0
1193 105 2
1040 107 2
1002 101 1
1015 102 2
1006 101 1
1034 106 2
1035 106 2
1016 103 2
1007 101 1
1036 107 2
1018 103 2
1026 105 2
1027 105 2
1183 104 2
1038 107 2
1025 105 2
1037 107 2
1021 104 2
1019 103 2
1005 101 1
1179 105 2
update ignore t1 set id=id+1;
select * from t1;
id parent_id level
1002 100 0
1004 101 1
1005 101 1
1009 102 2
1025 102 2
1018 103 2
1023 104 2
1025 104 2
1029 105 2
1030 105 2
1031 105 2
1032 106 2
1033 106 2
1034 106 2
1204 107 2
1203 107 2
1021 103 2
1158 100 0
1194 105 2
1041 107 2
1003 101 1
1016 102 2
1007 101 1
1035 106 2
1036 106 2
1017 103 2
1008 101 1
1037 107 2
1019 103 2
1027 105 2
1028 105 2
1184 104 2
1039 107 2
1026 105 2
1038 107 2
1022 104 2
1020 103 2
1006 101 1
1180 105 2
update ignore t1 set id=1023 where id=1010;
select * from t1 where parent_id=102;
id parent_id level
1009 102 2
1025 102 2
1016 102 2
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 6 Using where; Using index
select level,id from t1 where level=1;
level id
1 1004
1 1005
1 1003
1 1007
1 1008
1 1006
select level,id,parent_id from t1 where level=1;
level id parent_id
1 1004 101
1 1005 101
1 1003 101
1 1007 101
1 1008 101
1 1006 101
select level,id from t1 where level=1 order by id;
level id
1 1003
1 1004
1 1005
1 1006
1 1007
1 1008
delete from t1 where level=1;
select * from t1;
id parent_id level
1002 100 0
1009 102 2
1025 102 2
1018 103 2
1023 104 2
1025 104 2
1029 105 2
1030 105 2
1031 105 2
1032 106 2
1033 106 2
1034 106 2
1204 107 2
1203 107 2
1021 103 2
1158 100 0
1194 105 2
1041 107 2
1016 102 2
1035 106 2
1036 106 2
1017 103 2
1037 107 2
1019 103 2
1027 105 2
1028 105 2
1184 104 2
1039 107 2
1026 105 2
1038 107 2
1022 104 2
1020 103 2
1180 105 2
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)
) type = innodb ;
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, primary key (a)) type=innodb;
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
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) type=innodb;
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 error The handler for the table doesn't support optimize
show keys from t1;
Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment
t1 0 PRIMARY 1 a A 2 NULL NULL BTREE
drop table t1;
create table t1 (i int, j int ) TYPE=innodb;
insert into t1 values (1,2);
select * from t1 where i=1 and j=2;
i j
1 2
create index ax1 on t1 (i,j);
select * from t1 where i=1 and j=2;
i j
1 2
drop table t1;
CREATE TABLE t1 (
a int3 unsigned NOT NULL,
b int1 unsigned NOT NULL,
UNIQUE (a, b)
) TYPE = innodb;
INSERT INTO t1 VALUES (1, 1);
SELECT MIN(B),MAX(b) FROM t1 WHERE t1.a = 1;
MIN(B) MAX(b)
1 1
drop table t1;
CREATE TABLE t1 (a int unsigned NOT NULL) type=innodb;
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) type = innodb;
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 > 0 and a < 50;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range PRIMARY PRIMARY 4 NULL 1 Using where
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)) type=innodb;
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');
Duplicate entry '1-1' for key 1
select id from t1;
id
0
1
2
select id from t1;
id
0
1
2
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)) type=innodb;
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');
Duplicate entry '1-1' for key 1
select id from t1;
id
0
1
2
insert ignore into t1 values (100,1,2,'D'),(1,1,99,'D');
commit;
select id,id3 from t1;
id id3
0 0
1 1
2 2
100 2
UNLOCK TABLES;
DROP TABLE t1;
create table t1 (a char(20), unique (a(5))) type=innodb;
Incorrect sub part key. The used key part isn't a string, the used length is longer than the key part or the table handler doesn't support unique sub keys
create table t1 (a char(20), index (a(5))) type=innodb;
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`a` char(20) character set latin1 default NULL,
KEY `a` (`a`)
) TYPE=InnoDB CHARSET=latin1
drop table t1;
create temporary table t1 (a int not null auto_increment, primary key(a)) type=innodb;
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)
) type=innodb;
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) type= innodb;
insert into mysqltest.t1 values(1);
create table mysqltest.t2 (a int not null) type= myisam;
insert into mysqltest.t2 values(1);
create table mysqltest.t3 (a int not null) type= heap;
insert into mysqltest.t3 values(1);
commit;
drop database mysqltest;
show tables from mysqltest;
Got one of the listed errors
set autocommit=0;
create table t1 (a int not null) type= innodb;
insert into t1 values(1),(2);
truncate table t1;
Can't execute the given command because you have active locked tables or an active transaction
commit;
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) type= innodb;
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)) type=innodb;
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 index NULL PRIMARY 4 NULL 4
explain select * 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 4
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 4 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 4 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 4 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 index NULL b 4 NULL 4 Using index
explain select a,b from t1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index NULL b 4 NULL 4 Using index
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 4
drop table t1;
create table t1 (t int not null default 1, key (t)) type=innodb;
desc t1;
Field Type Null Key Default Extra
t int(11) 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(14) NOT NULL,
last_mod_id smallint(6) NOT NULL default '0',
last_app_date timestamp(14) NOT NULL,
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'
) TYPE=InnoDB;
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(14) NOT NULL,
last_mod_id smallint(6) NOT NULL default '0',
last_app_date timestamp(14) NOT NULL,
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'
) TYPE=InnoDB;
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 90 2 2002-01-11 11:28:46 500 0000-00-00 00:00:00 -1 2 3 1
9197722223 berry 90 3 2002-01-11 11:28:09 500 2002-01-02 11:45:32 501 4 10 0
650 San Francisco 0 0 2001-12-27 11:13:36 342 0000-00-00 00:00:00 -1 1 24 1
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 520 1 2002-01-02 11:52:34 500 2002-01-02 11:52:59 501 33 32768 0
333 tubs 99 2 2002-01-09 11:34:40 501 2002-01-09 11:34:40 500 3 10 0
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 0 2 2002-01-11 11:28:53 500 0000-00-00 00:00:00 -1 2 3 1
9197722223 berry 90 3 2002-01-11 11:28:18 500 2002-01-02 11:45:32 501 4 10 0
650 San Francisco 90 0 2002-01-09 11:31:58 342 0000-00-00 00:00:00 -1 1 24 1
333 tubs 99 2 2002-01-09 11:34:53 501 2002-01-09 11:34:53 500 3 10 0
delete t1, t2 from t1 left join t2 on t1.number=t2.number where (t1.carrier_id=90 and t1.number=t2.number) or (t2.carrier_id=90 and t1.number=t2.number) or (t1.carrier_id=90 and 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 520 1 2002-01-02 11:52:34 500 2002-01-02 11:52:59 501 33 32768 0
333 tubs 99 2 2002-01-09 11:34:40 501 2002-01-09 11:34:40 500 3 10 0
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 99 2 2002-01-09 11:34:53 501 2002-01-09 11:34:53 500 3 10 0
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 99 2 2002-01-09 11:34:53 501 2002-01-09 11:34:53 500 3 10 0
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)) type=innodb;
BEGIN;
SET SESSION TRANSACTION ISOLATION LEVEL SERIALIZABLE;
SELECT @@tx_isolation,@@global.tx_isolation;
@@tx_isolation @@global.tx_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
1 1 Tim
2 1 Monty
3 2 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
1 1 Tim
2 1 Monty
3 2 David
4 2 Erik
5 3 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
1 1 Tim
2 1 Monty
3 2 David
4 2 Erik
5 3 Sasha
6 3 Jeremy
7 4 Matt
COMMIT;
DROP TABLE t1;
drop table if exists t1,t2;
create table t1 (n int(10), d int(10)) type=innodb;
create table t2 (n int(10), d int(10)) type=innodb;
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
1 10
1 10
select * from t2;
n d
1 30
2 20
drop table t1,t2;
create table t1 (a int, b int) type=innodb;
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) type=myisam;
create table t2 (b varchar(10) not null unique) type=innodb;
select t1.a from t1,t2 where t1.a=t2.b;
a
drop table t1,t2;
|