Re: Question on oid's

On Wed, 2002-04-10 at 18:38, Joseph Molnar wrote:
> I am also new to Postgresql though not ORDBMS systems ... why should you not
> use OIDs as a primary key in Postgresql?

Because they will be different next time you load your data from a dump.

Cheers,
Andrew.
>
> ----- Original Message -----
> From: "Josh Berkus" <josh(at)agliodbs(dot)com>
> To: "Juliet May" <jmay(at)speark(dot)com>; <pgsql-novice(at)postgresql(dot)org>
> Sent: Tuesday, April 09, 2002 11:19 PM
> Subject: Re: [NOVICE] Question on oid's
>
>
> > Juliet,
> >
> > > My first question is about oid's. What are they exactly and when
> > > should/shouldn't I use them. I had trouble finding any information on
> > > them in either the online documentation or the online books. I'm
> > > using pgadmin to develop my database and I noticed that once I select
> > > or don't select oid that I can't change my mind.
> >
> > We need a FAQ on this. Sigh.
> >
> > OIDs are for system use. Occasionally some developers will build
> > transaction tables, to which thousands or millions of records will be
> > written and erased per day. For that case (and that case only) they
> > will build "OID-less tables" in Postgres 7.2.
> >
> > Otherwise, you should build your tables with OIDs, but then ignore the
> > OIDs and not use them as an index. The system helps by "hiding" the
> > OID column from you.

I don't agree with this statement though. I don't personally see much
value in having OID's in my tables in general. Obviously they are
needed for (most) system tables, but why should I bother with them
normally.

What system use is made of OIDs in non-system tables? None?

> > Should you run across documentation suggesting that you use the OID as
> > an index or primary, key, that documentation is outdated.

And was possibly suspect in the first place.

Cheers,
Andrew.

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