Re: [SQL] Very disappointing performance -- All Indexes Ignored.

> > Second, indexes are not of a huge value in this query, because there are
> > no restrictions, i.e. x=3. In most cases, walking the index and then
> > going to the heap table takes longer than just reading the entire table
> > into a hash and doing the join there.
>
> I see, and after doing a more specific query(from_job_id=xxx) the speed
> is much increased... The main thing that disturbed me is the rather large
> time between the query with joins(300 seconds) and with the functions(30s)...
> Shouldn't the functions be far slower?(Seems like they would be less
> efficient)

Well, you are doing the functions only for matched rows, while the other
does full-table joins. Can you easily test the snapshot and let me
know? I have re-done the optimizer for not-yet-released 6.5, and that
may fix the problem. I fixed many optimizer problems, and it may be
choosing a non-optimal join path.

>
> PostgreSQL is also crashing 1-2 times a day on me, although I have a
> handy perl script to keep it alive now <grin>... If PostgreSQL does work for
> my project I'll of course buy CDs/books/whatever to support the project.
> Despite the 2 problems I'm having I am very impressed with the project.

That is strange. Don't here that much.

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