2010/1/25 Yang Zhang <yanghatespam@stripped>:
> Right, I saw the docs. I'm fine with creating an index on it, but the
> only way I've successfully created a table with auto_increment is by
> making it a primary key. And I still don't understand why this
> requirement is there in the first place.
Non-primary key works for me, as documented:
---------------------------------->8--------------------------------
mysql> create table test_ai (i int PRIMARY KEY, c int auto_increment, index(c));
Query OK, 0 rows affected (0,07 sec)
mysql> desc test_ai;
+-------+---------+------+-----+---------+----------------+
| Field | Type | Null | Key | Default | Extra |
+-------+---------+------+-----+---------+----------------+
| i | int(11) | NO | PRI | NULL | |
| c | int(11) | NO | MUL | NULL | auto_increment |
+-------+---------+------+-----+---------+----------------+
2 rows in set (0,00 sec)
mysql> insert into test_ai (i) values (100), (200);
Query OK, 2 rows affected (0,00 sec)
Records: 2 Duplicates: 0 Warnings: 0
mysql> select * from test_ai;
+-----+---+
| i | c |
+-----+---+
| 100 | 1 |
| 200 | 2 |
+-----+---+
2 rows in set (0,00 sec)
---------------------------------->8--------------------------------
Regards,
--
Jaime Crespo
MySQL & Java Instructor
Warp Networks
<http://warp.es>
