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stop slave;
drop table if exists t1,t2,t3,t4,t5,t6,t7,t8,t9;
reset master;
reset slave;
drop table if exists t1,t2,t3,t4,t5,t6,t7,t8,t9;
start slave;
create table t1 (a int not null auto_increment,b int, primary key (a)) engine=myisam auto_increment=3;
insert into t1 values (NULL,1),(NULL,2),(NULL,3);
select * from t1;
a b
12 1
22 2
32 3
select * from t1;
a b
12 1
22 2
32 3
drop table t1;
create table t1 (a int not null auto_increment,b int, primary key (a)) engine=myisam;
insert into t1 values (1,1),(NULL,2),(3,3),(NULL,4);
delete from t1 where b=4;
insert into t1 values (NULL,5),(NULL,6);
select * from t1;
a b
1 1
2 2
3 3
22 5
32 6
select * from t1;
a b
1 1
2 2
3 3
22 5
32 6
drop table t1;
set @@session.auto_increment_increment=100, @@session.auto_increment_offset=10;
show variables like "%auto_inc%";
Variable_name Value
auto_increment_increment 100
auto_increment_offset 10
create table t1 (a int not null auto_increment, primary key (a)) engine=myisam;
insert into t1 values (NULL),(5),(NULL);
insert into t1 values (250),(NULL);
select * from t1;
a
5
10
110
250
310
insert into t1 values (1000);
set @@insert_id=400;
insert into t1 values(NULL),(NULL);
select * from t1;
a
5
10
110
250
310
400
410
1000
select * from t1;
a
5
10
110
250
310
400
410
1000
drop table t1;
create table t1 (a int not null auto_increment, primary key (a)) engine=innodb;
insert into t1 values (NULL),(5),(NULL);
insert into t1 values (250),(NULL);
select * from t1;
a
5
10
110
250
310
insert into t1 values (1000);
set @@insert_id=400;
insert into t1 values(NULL),(NULL);
select * from t1;
a
5
10
110
250
310
400
410
1000
select * from t1;
a
5
10
110
250
310
400
410
1000
drop table t1;
set @@session.auto_increment_increment=1, @@session.auto_increment_offset=1;
create table t1 (a int not null auto_increment, primary key (a)) engine=myisam;
insert into t1 values (NULL),(5),(NULL),(NULL);
insert into t1 values (500),(NULL),(502),(NULL),(NULL);
select * from t1;
a
1
5
6
7
500
501
502
503
504
set @@insert_id=600;
insert into t1 values(600),(NULL),(NULL);
ERROR 23000: Duplicate entry '600' for key 1
set @@insert_id=600;
insert ignore into t1 values(600),(NULL),(NULL),(610),(NULL);
select * from t1;
a
1
5
6
7
500
501
502
503
504
600
610
611
select * from t1;
a
1
5
6
7
500
501
502
503
504
600
610
611
drop table t1;
set @@session.auto_increment_increment=10, @@session.auto_increment_offset=1;
create table t1 (a int not null auto_increment, primary key (a)) engine=myisam;
insert into t1 values(2),(12),(22),(32),(42);
insert into t1 values (NULL),(NULL);
insert into t1 values (3),(NULL),(NULL);
select * from t1;
a
1
3
11
21
31
select * from t1;
a
1
2
3
11
12
21
22
31
32
42
drop table t1;
create table t1 (a tinyint not null auto_increment primary key) engine=myisam;
insert into t1 values(103);
set auto_increment_increment=11;
set auto_increment_offset=4;
insert into t1 values(null);
insert into t1 values(null);
insert into t1 values(null);
ERROR 23000: Duplicate entry '125' for key 1
select a, mod(a-@@auto_increment_offset,@@auto_increment_increment) from t1 order by a;
a mod(a-@@auto_increment_offset,@@auto_increment_increment)
103 0
114 0
125 0
create table t2 (a tinyint unsigned not null auto_increment primary key) engine=myisam;
set auto_increment_increment=10;
set auto_increment_offset=1;
set insert_id=1000;
insert into t2 values(null);
Warnings:
Warning 1264 Out of range value adjusted for column 'a' at row 1
select a, mod(a-@@auto_increment_offset,@@auto_increment_increment) from t2 order by a;
a mod(a-@@auto_increment_offset,@@auto_increment_increment)
251 0
create table t3 like t1;
set auto_increment_increment=1000;
set auto_increment_offset=700;
insert into t3 values(null);
Warnings:
Warning 1264 Out of range value adjusted for column 'a' at row 1
select * from t3 order by a;
a
127
select * from t1 order by a;
a
103
114
125
select * from t2 order by a;
a
251
select * from t3 order by a;
a
127
drop table t1,t2,t3;
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