Re: [SQL] maximum number of rows in table - what about oid limits? - Mailing list pgsql-general

From Stephan Szabo
Subject Re: [SQL] maximum number of rows in table - what about oid limits?
Date
Msg-id Pine.BSF.4.21.0106061050520.16377-100000@megazone23.bigpanda.com
Whole thread Raw
Responses Re: [SQL] maximum number of rows in table - what about oid limits?  (John Scott <jmscott@yahoo.com>)
List pgsql-general
On 6 Jun 2001, jmscott@REMOVEMEyahoo.com wrote:

> postgresql docs claim an essentially unlimited number of
> rows per table.
>
>    http://postgresql.crimelabs.net/users-lounge/limitations.html
>
> this doesn't make sense if each row has an oid.
> do more subtle side effects exist if the oid wraps?

In general, unless you're relying on unique oids, you should be fine.
You probably don't want to use oid as a unique key in your tables for that
reason. Of course, sequences aren't sufficient either (also being
int4) but some kind of int8 "sequence" mechanism would do it if you expect
more than the int4 number of rows.

You might have problems with creating system table entries with unique
oids after wraparound, but generally that can be fixed by trying again.
(Some of the system tables have a unique index on oid).


pgsql-general by date:

Previous
From: Doug McNaught
Date:
Subject: Re: "trigger"ing a procedure every X minutes
Next
From: Gilles DAROLD
Date:
Subject: Re: Something odd with Postgresql 6.5