From: "H.J. Sanders" <hjs@rmax.nl>
To: "Merlin Moncure" <mmoncure@gmail.com>, "Simon Dale" <sdale@rm.com>
Cc: <pgsql-performance@postgresql.org>
Subject: Re: Stored Procedure Performance
Date: Tue, 11 Apr 2006 16:02:51 +0200
Message-ID: <GMEAJIDMNDKCIHMMHDFLEEGMDKAA.hjs@rmax.nl>
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Hello

At my little machine (pentium 4, 2.8 Ghz, 256 Mb RAM, Suse linux 9)
I can process about 100000 records a minute using the next setup:

begin work

begin for
	processing
	if 10.000 records processed:
		commit work
		begin work
	end if
end for

commit work (!)

Regards

Henk Sanders


> -----Oorspronkelijk bericht-----
> Van: pgsql-performance-owner@postgresql.org
> [mailto:pgsql-performance-owner@postgresql.org]Namens Merlin Moncure
> Verzonden: dinsdag 11 april 2006 15:50
> Aan: Simon Dale
> CC: pgsql-performance@postgresql.org
> Onderwerp: Re: [PERFORM] Stored Procedure Performance
> 
> 
> On 4/11/06, Simon Dale <sdale@rm.com> wrote:
> > I'm trying to evaluate PostgreSQL as a database that will have to store a
> > high volume of data and access that data frequently. One of the features on
> > our wish list is to be able to use stored procedures to access the data and
> > I was wondering if it is usual for stored procedures to perform slower on
> > PostgreSQL than raw SQL?
> 
> pl/pgsql procedures are a very thin layer over the query engine. 
> Generally, they run about the same speed as SQL but you are not making
> apples to apples comparison.  One of the few but annoying limitations
> of pl/pgsql procedures is that you can't return a select directly from
> the query engine but have to go through the return/return next
> paradigm which will be slower than raw query for obvious reasons.
> 
> You can however return a refcursor and you may want to look at them in
> situations where you want to return arbitrary sets outside the query
> engine or between pl/pgsql functions.  An example of using refcurors
> in that way is on my blog at
> http://people.planetpostgresql.org/merlin/index.php?/archives/2-Dealing-With-Recursive-Sets-With-PLPGSQL.html
> 
> Generally, in my opinion if you want to really unlock the power of
> postgresql you have to master pl/pgsql.  Go for it...it will work and
> work well.
> 
> merlin
> 
> merlin
> 
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