Re: [HACKERS] JDBC pg_description update needed for CVS tip

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От Rene Pijlman
Тема Re: [HACKERS] JDBC pg_description update needed for CVS tip
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Msg-id 1gpmpt8k3smepmrscaj8afoskacq6r51ri@4ax.com
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Ответ на Re: [HACKERS] JDBC pg_description update needed for CVS  (Jeroen van Vianen <jeroen.van.vianen@satama.com>)
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On Sun, 09 Sep 2001 14:48:41 +0200, you wrote:
>It is of course a performance improvement if it uses only 1 SQL statement
>rather than N+1 with N being the number of columns reported. E.g. if you
>list all columns of all tables in a big database, this would be a huge win.

I think that can only be decided by measurement.

What you're saying is:

    1 * c1 < (N + 1) * c2

but that can only be decided if we know c1 and c2 (meaning: the
execution times of two different queries, including round trip
overhead).

That doesn't mean I'm opposed to the change, on the contrary. As
a rule, I find a complex SQL statement more elegant than the
same 'algorithm' in procedural code. But in this case I wasn't
sure how to construct it.

Regards,
René Pijlman <rene@lab.applinet.nl>

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