Re: Foreign key constraints

From: Thomas Kyte <tkyte_at_us.oracle.com>
Date: Fri, 18 Jun 1999 13:33:04 GMT
Message-ID: <3771433d.4404403@newshost.us.oracle.com>

A copy of this was sent to Kenneth C Stahl <kstahl_at_lucent.com> (if that email address didn't require changing) On Fri, 18 Jun 1999 08:49:54 -0400, you wrote:

>Question: If a foreign key constraint is created for a column in a
>table, is it required that there be an index on that column? One book I
>read suggested that if there isn't an index for the column then there
>may be locking problems when updates occur.
>
>Ken

It is not required.

For a discussion of why you want to index them and a script to help detect unindexed foreign keys see http://govt.us.oracle.com/~tkyte/

--
See http://govt.us.oracle.com/~tkyte/ for my columns 'Digging-in to Oracle8i'... Current article is "Fine Grained Access Control", added June 8'th

Thomas Kyte                   tkyte_at_us.oracle.com
Oracle Service Industries     Reston, VA   USA

Opinions are mine and do not necessarily reflect those of Oracle Corporation Received on Fri Jun 18 1999 - 08:33:04 CDT