> >> If a primary key exists for a collection that is known never to change, > >> for example social security number, student registration number, or > >> employee number, then no additional system-assigned UID is required.
In point of fact Social security numbers *can* change. -- greg ---------------------------(end of broadcast)--------------------------- TIP 1: if posting/reading through Usenet, please send an appropriate subscribe-nomail command to [EMAIL PROTECTED] so that your message can get through to the mailing list cleanly