In my opinion, having a database for each site would require a lot of unnecessary work, as you would have to connect to every database in order to handle the sites. Having one database with tables for all the sites would be more productive as you would not have to change the connection info for PHP every time you want to use a different database. I use the PDO mysql adapter, what do you use? -----Original Message----- From: AndrÃs G. MontaÃez [mailto:andresmontanez@xxxxxxxxx] Sent: Wednesday, October 27, 2010 9:19 AM To: Ethan Rosenberg Cc: php-db-lists.php.net Subject: Re: Incrementing Primary Key Hi Ethan, in this case, you should manage the "keys" by your application, and store the used ids in aonther table, similar to a "sequence" in Oracle or Postgresql. Thats so if you want all the records un one table (a field for the letter, and the other for the numeric part). Otherwise, having a table for each site will be enough, as Jimmy suggests. -- AndrÃs G. MontaÃez Zend Certified Engineer Montevideo - Uruguay -- PHP Database Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php -- PHP Database Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php