Message-ID: <4A8C170C.1050703@portavita.nl>
Date: Wed, 19 Aug 2009 17:15:24 +0200
From: Yeb Havinga <yeb.havinga@portavita.nl>
Reply-To: y.t.havinga@mgrid.net
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To: Craig Ringer <craig@postnewspapers.com.au>
CC: pgsql-sql@postgresql.org
Subject: Re: Multiple simultaneous queries on single connection
References: <4A8951C5.5030107@portavita.nl>
	<4A8B56E2.6050704@postnewspapers.com.au>
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Hello Craig, list
>> Is there a way to have two or more connections see each others
>> uncommitted things?
>
> Not at present.
>
> You should be able to use explicitly declared cursors and FETCH to 
> interleave requests for results from one or more queries in the same 
> transation using the one connection, but only one FETCH may be active 
> at a time.
Thanks for your info. I verified with a pl/pgsql function that from a 
pl/pgsql perspective, this is a good solution. However, our client 
application needs to access the postgres backend with libpq. I'm 
currently looking at PQsendPrepare / PQSendQueryPrepared together with 
what the exec_execute_message does. Each of these has a portal name as 
parameter. It would be nice if PQgetResult could also provide a portal 
name to fetch a result from. The question is how to multiplex data from 
different portals on the tcp/ip connection, or maybe have more than one 
tcp/ip connection per PQconn object when more than one portal is active 
at the same time.

--
Yeb