Re: Record number

From: Larry Linson (bouncer_at_localhost.not)
Date: 08/26/04 

Date: Wed, 25 Aug 2004 22:46:19 -0500

"ctdak" wrote

> Thanks for the info. Pardon my ignorance,
> but where is the unique ID of the record
> that you say is a field in the record? I have
> never seen that field.

Generally, some individual field or some combination of fields taken
together uniquely identify each record. That is the "unique id" I was
talking about, not some database-generated property. It is, of course,
possible to create tables that do not have unique records, and thus, no
unique id, but it is rare to see that in a well-designed, normalized,
relational database.

Autonumbers are often used as "surrogate keys" for convenience in creating
joins where it takes a combination of several fields to uniquely identify
the record. Some database designers _always_ use an autonumber surrogate
key, even if the record is uniquely identified by a single field, but that
is an unnecessary complication.

   Larry Linson
   Microsoft Access MVP

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