Re: How to associate Foreign Key with an Index?

From: John K. Hinsdale <hin_at_alma.com>
Date: 8 Feb 2007 05:32:13 -0800
Message-ID: <1170941533.142695.105530@p10g2000cwp.googlegroups.com>

On Feb 8, 7:15 am, "sybrandb" <sybra..._at_gmail.com> wrote:

> And FKs do NOT have to be indexed.

A counterexample, i.e., a foreign key that exists without some sort of index enforcing uniqueness of its referenced column(s), would be very helpful. However I'm thinking no such counterexample will be forthcoming, the situation not being allowed in Oracle, if I understand things correctly.

> a FK is NOT
> automatically indexed when you create the FK.

Right (for Oracle at least), and I don't believe anyone is making any such claim.

If there is an example of an "indexless" FK, I'd be interested to see it, as it would help to clarify my understanding of what Oracle requires to enforce FKs.

Thanks,
John Hinsdale Received on Thu Feb 08 2007 - 07:32:13 CST