What does it mean? Plan stats and double rainbows.

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От Michael Moore
Тема What does it mean? Plan stats and double rainbows.
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Msg-id CACpWLjO4CG7qwcd9thirpSR5+YDHSmeYeSoefPeuXYSdBfCqKg@mail.gmail.com
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Ответы Re: What does it mean? Plan stats and double rainbows.  (Thomas Kellerer <spam_eater@gmx.net>)
Re: What does it mean? Plan stats and double rainbows.  ("David G. Johnston" <david.g.johnston@gmail.com>)
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I'm having a difficult time finding documentation on EXPLAIN PLAN stats. For example, in
'                    ->  Nested Loop Left Join  (cost=0.43..1415.06 rows=2 width=1377) (actual time=0.093..0.093 rows=0 loops=1)'
what does 0.43..1415.06 mean? Is that a range? If so, it seems rather pointless, like saying "somewhere between 0 and infinity".

Also, is there a way to tell the query planner to limit the search for the best plan on a per statement basis. I know that this exists as a config parameter but I think that applies to the entire database. I have a query that takes 9 times more time to plan than it does to execute. 

Tia,
Mike

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