Go back to that post and click the "response to Celada" link I had. I made it clear that the presense of a unique key is not enough. The duplicates are an issue in that case because the table is not in 3NF. If the table is is 3NF, then that unique constraint across all keys holds.

Cheers,
Ovid

New address of my CGI Course.

In reply to Re^6: (OT) Why SQL Sucks (with a little Perl to fix it) by Ovid
in thread (OT) Why SQL Sucks (with a little Perl to fix it) by Ovid

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