Re: SELECT's take a long time compared to other DBMS

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От Christopher Browne
Тема Re: SELECT's take a long time compared to other DBMS
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Msg-id m33cfd6xss.fsf@chvatal.cbbrowne.com
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Ответ на SELECT's take a long time compared to other DBMS  ("Relaxin" <me@yourhouse.com>)
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In the last exciting episode, "Relaxin" <me@yourhouse.com> wrote:
> All queries were ran on the SERVER for all of the databases I tested.

Queries obviously run "on the server."  That's kind of the point of
the database system being a "client/server" system.

The question is what client program(s) you used to process the result
sets.  I'd be surprised to see any client process 100K records in any
meaningful way in much less than 30 seconds.  Rendering that much data
into a console will take some time.  Drawing it into cells on a GUI
window will take a lot more time.

Supposing you were using a graphical client, it would be unsurprising
for it to have submitted something equivalent to "limit 30 rows" (or
whatever you can display on screen), and defer further processing 'til
later. If that were the case, then 26s to process the whole thing
would be a lot more efficient than 5-6s to process a mere 30 rows...

> This is all resulting data for all of the databases that I tested.

You seem to have omitted "all resulting data."
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