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Date: Thu, 2 Jun 2011 18:07:30 +0300
From: Pavel Golub <pavel@microolap.com>
Reply-To: Pavel Golub <pavel@gf.microolap.com>
Organization: Microolap
X-Priority: 3 (Normal)
Message-ID: <1003921930.20110602180730@gf.microolap.com>
To: Alvaro Herrera <alvherre@commandprompt.com>
CC: Andrew Chernow <ac@esilo.com>, Pavel Golub <pavel@microolap.com>,
	PostgreSQL Hackers <pgsql-hackers@postgresql.org>,
	pgsql-interfaces <pgsql-interfaces@postgresql.org>
Subject: Re: [HACKERS] PQdeleteTuple function in libpq
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References: <147534417.20110601184310@gf.microolap.com>
	<4DE6A5B7.2070700@esilo.com>
	<707574086.20110602112826@gf.microolap.com>
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Hello, Alvaro.

You wrote:

AH> Excerpts from Andrew Chernow's message of jue jun 02 10:12:40 -0400 2011:

>> > Andrew, why we have PQmakeEmptyPGresult, PQcopyResult,
>> > PQsetResultAttrs, PQsetvalue and PQresultAlloc in this case? Of course
>> > there's no big deal with their absence but let's be consistent.
>> 
>> I'm not entirely sure what you are trying to do, but can't you use 
>> PQmakeEmptyPGresult, PQsetResultAttrs and PQsetvalue to construct a 
>> result that excludes the tuples you don't want followed by a 
>> PQclear(initial_result)?

AH> Seems pretty wasteful if you want to delete a single tuple from a large
AH> result.  I think if you desired to compact the result to free some
AH> memory after deleting a large fraction of the tuples in the result it
AH> could be useful to do that, otherwise just live with the unused holes in
AH> the storage area as suggested by Pavel.

Totally! Thanks Alvaro.




-- 
With best wishes,
 Pavel                          mailto:pavel@gf.microolap.com