Re:

On Sat, 2003-02-08 at 04:48, greg@turnstep.com wrote:
> > Greg Sabino Mullane (in the other thread) suggested the following alternate,
> > but it ran slightly slower on my machine than the original.
> >
> > SELECT id, date, value FROM sample a WHERE date <='2003-01-01' AND oid =
> > (SELECT oid FROM sample WHERE id = a.id AND DATE <='2003-01-01' ORDER BY
> > date DESC LIMIT 1)
> > ORDER BY id;
>
> You should check this again. There is no way that my query is slower, as
> long as you have an index on the "date" column and have run an ANALYZE on
> the "sample" table.

Wouldn't there need to be an index on OID for your query to be fast?

Cheers,
                    Andrew.
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