Re: effective SELECT from child tables

On Sat, Oct 01, 2005 at 04:35:49PM +0200, Martijn van Oosterhout wrote:
> On Sat, Oct 01, 2005 at 10:05:22AM -0400, mark(at)mark(dot)mielke(dot)cc wrote:
> > It has the 'side or additional benefit' being requested here. The ability
> > to filter the child table by some attribute. For example, if the child
> > tables are used for partitioning, and the attribute were to keep a date
> > range, the field restriction optimization could be used to automatically
> > determine the set of tables to use for the date range specified. With
> > such a change, it would even work automatically if the date ranges
> > overlapped for some reason. Selecting a table name by date is hacky. This
> > sort of solution would be a general solution to the problem.
> This is what "Constraint Exclusion" does. It uses CHECK constraints on
> a table to filter out tables that obviously don't apply to a query.

Good point. I'll have to invent another use case. :-)

> It's just the the specific case of "tableoid = XXX" is not supported
> right now.

Yes. This is what I was looking for Simon to admit. :-)

Cheers,
mark

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