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drop table if exists t1;
create table t1 (a int not null auto_increment,b int, primary key (a)) type=myisam auto_increment=3;
insert into t1 values (1,1),(NULL,3),(NULL,4);
delete from t1 where a=4;
insert into t1 values (NULL,5),(NULL,6);
select * from t1;
a b
1 1
3 3
5 5
6 6
delete from t1 where a=6;
replace t1 values (3,1);
ALTER TABLE t1 add c int;
replace t1 values (3,3,3);
insert into t1 values (NULL,7,7);
update t1 set a=8,b=b+1,c=c+1 where a=7;
insert into t1 values (NULL,9,9);
select * from t1;
a b c
1 1 NULL
3 3 3
5 5 NULL
8 8 8
9 9 9
drop table t1;
create table t1 (
skey tinyint unsigned NOT NULL auto_increment PRIMARY KEY,
sval char(20)
);
insert into t1 values (NULL, "hello");
insert into t1 values (NULL, "hey");
select * from t1;
skey sval
1 hello
2 hey
select _rowid,t1._rowid,skey,sval from t1;
_rowid _rowid skey sval
1 1 1 hello
2 2 2 hey
drop table t1;
create table t1 (a char(10) not null, b int not null auto_increment, primary key(a,b));
insert into t1 values ("a",1),("b",2),("a",2),("c",1);
insert into t1 values ("a",NULL),("b",NULL),("c",NULL),("e",NULL);
insert into t1 (a) values ("a"),("b"),("c"),("d");
insert into t1 (a) values ('k'),('d');
insert into t1 (a) values ("a");
insert into t1 values ("d",last_insert_id());
select * from t1;
a b
a 1
a 2
a 3
a 4
a 5
b 2
b 3
b 4
c 1
c 2
c 3
d 1
d 2
d 5
e 1
k 1
drop table t1;
create table t1 (ordid int(8) not null auto_increment, ord varchar(50) not null, primary key (ordid), index(ord,ordid));
insert into t1 (ordid,ord) values (NULL,'sdj'),(NULL,'sdj');
select * from t1;
ordid ord
1 sdj
2 sdj
drop table t1;
create table t1 (ordid int(8) not null auto_increment, ord varchar(50) not null, primary key (ord,ordid));
insert into t1 values (NULL,'sdj'),(NULL,'sdj'),(NULL,"abc"),(NULL,'abc'),(NULL,'zzz'),(NULL,'sdj'),(NULL,'abc');
select * from t1;
ordid ord
1 abc
2 abc
3 abc
1 sdj
2 sdj
3 sdj
1 zzz
drop table t1;
create table t1 (sid char(5), id int(2) NOT NULL auto_increment, key(sid, id));
create table t2 (sid char(20), id int(2));
insert into t2 values ('skr',NULL),('skr',NULL),('test',NULL);
insert into t1 select * from t2;
select * from t1;
sid id
skr 1
skr 2
test 1
drop table t1,t2;
create table t1 (a int not null primary key auto_increment);
insert into t1 values (0);
update t1 set a=0;
select * from t1;
a
0
check table t1;
Table Op Msg_type Msg_text
test.t1 check warning Found row where the auto_increment column has the value 0
test.t1 check status OK
drop table t1;
create table t1 (a int not null auto_increment primary key);
insert into t1 values (NULL);
insert into t1 values (-1);
select last_insert_id();
last_insert_id()
1
insert into t1 values (NULL);
select * from t1;
a
-1
1
2
drop table t1;
create table t1 (a int not null auto_increment primary key) /*!40102 type=heap */;
insert into t1 values (NULL);
insert into t1 values (-1);
select last_insert_id();
last_insert_id()
1
insert into t1 values (NULL);
select * from t1;
a
-1
1
2
drop table t1;
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