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@gene.com, http://www.gene.com/
Genentech, Inc. 650-225-6133 (voice), -5389 (fax)
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