drop table if exists t1;
create table t1 (a int not null);
insert into t1 values (1);
insert into t1 values (a+2);
insert into t1 values (a+3);
insert into t1 values (4),(a+5);
select * from t1;
a
1
2
3
4
5
drop table t1;
create table t1 (id int not null auto_increment primary key, username varchar(32) not null, unique (username));
insert into t1 values (0,"mysql");
insert into t1 values (0,"mysql ab");
insert into t1 values (0,"mysql a");
insert into t1 values (0,"r1manic");
insert into t1 values (0,"r1man");
drop table t1;