Re: Database normalization

On Tue, Aug 28, 2007 at 12:47:45PM +0100, Sebastian Ritter wrote:
> > The update/message format is exactly the same for both. Should I make two
> > different tables:

> > one table with extra columns : is_client, client_id, service_id, where
> > either client_id or service_id would be null depending on the is_client
> > boolean?

Is the rest of the data the same? If so, then one table is right.
If not, then more than one table. In either case, I really hate the
idea of two columns, one of which is always null. But if you're
going to do that, make sure you add a CHECK constraint where !(col1
IS NULL and col2 IS NULL).

A

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