Re: [PERFORM] Big IN() clauses etc : feature proposal - Mailing list pgsql-hackers

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Subject Re: [PERFORM] Big IN() clauses etc : feature proposal
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Msg-id op.s9cobvzhcigqcu@apollo13
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In response to Re: [PERFORM] Big IN() clauses etc : feature proposal  ("Jim C. Nasby" <jnasby@pervasive.com>)
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> Have you tried getting a profile of what exactly PostgreSQL is doing
> that takes so long when creating a temp table?
Nope, I'm not proficient in the use of these tools (I stopped using C  
some time ago).

> BTW, I suspect catalogs might be the answer,
Probably, because :
- Temp tables don't use fsync (I hope)- Catalogs do- fsync=off makes COMMIT fast- fsync=on makes COMMIT slow- fsync=on
andusing ANALYZE makes COMMIT slower (more updates to the  
 
catalogs I guess)

> which is why Oracle has you
> define a temp table once (which does all the work of putting it in the
> catalog) and then you just use it accordingly in each individual
> session.
Interesting (except for the ANALYZE bit...)




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