Subject: Re: Query Fails with error calloc - Cannot alocate memory
From: Neil Conway <neilc@samurai.com>
To: Howard Oblowitz <Howard.Oblowitz@lewisgroup.co.za>
Cc: pgsql-performance@postgresql.org
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Date: Wed, 07 Dec 2005 01:31:37 -0500
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On Mon, 2005-12-05 at 09:42 +0200, Howard Oblowitz wrote:
> I am trying to run a query that selects 26 million rows from a
> table with 68 byte rows.
> 
> When run on the Server via psql the following error occurs:
> 
> calloc : Cannot allocate memory

That's precisely what I'd expect: the backend will process the query and
begin sending back the entire result set to the client. The client will
attempt to allocate a local buffer to hold the entire result set, which
obviously fails in this case.

You probably want to explicitly create and manipulate a cursor via
DECLARE, FETCH, and the like -- Postgres will not attempt to do this
automatically (for good reason).

> Postgres version is 7.3.4

You should consider upgrading, 7.3 is quite old. At the very least, you
should probably be using the most recent 7.3.x release, 7.3.11.

-Neil