From: Martijn Tonies
Date: November 17 2008 5:56pm
Subject: Re: normalised designs: customer database
List-Archive: http://lists.mysql.com/mysql/215251
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> >> If all you want to do is to restrict a field to certain values, and
> >aren't
> >> concerned with cascading operations, is a set more efficient than a
> >foreign
> >> key?
> >
> >A Set or Enum?
> >
> >I can understand "enum"s, but sets are evil.
> >
> [JS] Why is that? I've been using sets, but I could use enums. Set just
> seemed more appropriate for a small (two or three) number of values.

Besides the fact that they're non-portable, I don't think they can
be properly indexed either, that is, if they contain multiple possible
values of the set.

Martijn Tonies
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