Re: Air-traffic benchmark

On Thu, Jan 07, 2010 at 01:38:41PM +0100, Lefteris wrote:
> airtraffic=# EXPLAIN ANALYZE SELECT "DayOfWeek", count(*) AS c FROM
> ontime WHERE "Year" BETWEEN 2000 AND 2008 GROUP BY "DayOfWeek" ORDER
> BY c DESC;

Well, this query basically has to be slow. Correct approach to this
problem is to add precalculated aggregates - either with triggers or
with some cronjob.
Afterwards query speed depends only on how good are your aggregates,
and/or how detailed.
Of course calculating them is not free, but is done on write (or
periodically), and not on user-request, which makes user-requests *much*
faster.

depesz

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