On Wed, Oct 07, 2009 at 09:19:58PM +0200, Zsolt wrote:
> For a given house I would like to start the numbering of tenants from
> 1. Each house could have tenant_ID=1, obviously in this case the
> house_ID will differ. The combination of tenant_ID and house_ID will
> be the unique identifier of each tenant.
The term for this that tends to float around for this concept (in PG
anyway) is "gap-less sequences": this looks like a reasonable link:
http://www.varlena.com/GeneralBits/130.php
--
Sam http://samason.me.uk/