In article <Pine.LNX.4.33.0403021406090.4475-100000@css120.ihs.com>,
"scott.marlowe" <scott.marlowe@ihs.com> writes:
> On Tue, 2 Mar 2004, [UTF-8] PauloviÄ Michal wrote:
>> how you solve the problem with multilevel autoicrement?
>>
>> In MySQL you create table with col1, col2. Col 2 is AUTOICREMENT and you
>> have to create UNIQUE INDEX (Col1, Col2). If you insert to this table
>> for col1 volume 1, col2 automaticaly increase by one.
>>
>> Example:
>> Insert into table values (1);
>> Insert into table values (1);
>> Insert into table values (2);
>> Insert into table values (1);
>> Insert into table values (2);
> I did this in MySQL and got this:
> create table test (id1 int, id2 int auto_increment, primary key(id2));
> Query OK, 0 rows affected (0.00 sec)
mysql> alter table test add unique index (id1, id2);
> Query OK, 0 rows affected (0.09 sec)
> Records: 0 Duplicates: 0 Warnings: 0
You can't have a multi-level autoincrement if you make the second
level unique. Use the following instead:
create table test (id1 int, id2 int auto_increment, primary key(id1,id2));
Note that this trick works only for the MyISAM and BDB table types,
not for InnoDB.