Re: no dup rows

On Mon, 2004-08-02 at 11:32, Jodi Kanter wrote:

> I have a linking table that has only two fields in it and both are
> foreign keys to other tables. I'd like to ensure that there are never
> any duplicate rows in this table. I was planning on creating a
> multi-column unique index to satisfy this requirement. Is there a more
> appropriate way to accomplish this or am I on the right track?>

Yep, that is the correct way to impose this constraint.

I give constraints meaningful names prefixed by the table name (e.g.,
tablename_seq_already_in_set) so that the cause of an error is more
readily identifiable. This is particularly useful for insertions into
complex tables with multiple constraints.

-Reece
--
Reece Hart, Ph.D. rkh(at)gene(dot)com, http://www.gene.com/
Genentech, Inc. 650-225-6133 (voice), -5389 (fax)
Bioinformatics and Protein Engineering
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