> >The notion of a "variant record" exists in many programming languages.
> >Typically you have a selector to indicate which variant it is. There is
> >nothing at all wrong with using the same sort of construct in a database
> In O-O databases. I think the concept is not defined in relational
> database theory. Are you aware of the rel db rule regarding domains?
> >The only constraint you _really_ need to meet in a database is that
> you let
> >the database product do the things it needs to do so that the queries
> >make are O(log N) when possible. The rest is pure fluff. Beyond that,
> >there is no "should".
> Relational theory says otherwise.
I'm with Peter on this one, in relational theory and data modelling, there's
a lot of very well documented "should" :-)
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