Re: Out of memory error on huge resultset

From: Dave Cramer <Dave(at)micro-automation(dot)net>
To: Nick Fankhauser <nickf(at)ontko(dot)com>
Cc: pgsql-jdbc <pgsql-jdbc(at)postgresql(dot)org>
Subject: Re: Out of memory error on huge resultset
Date: 2002-10-10 15:35:48
Message-ID: 1034264150.1796.21.camel@inspiron.cramers
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Nick,

Use a cursor, the current driver doesn't support caching, the backend
gives you everything you ask for, you can't just say you want a limited
set.

So if you use cursors you can fetch a subset

Dave
On Thu, 2002-10-10 at 11:24, Nick Fankhauser wrote:
>
> I'm selecting a huge ResultSet from our database- about one million rows,
> with one of the fields being varchar(500). I get an out of memory error from
> java.
>
> If the whole ResultSet gets stashed in memory, this isn't really surprising,
> but I'm wondering why this happens (if it does), rather than a subset around
> the current record being cached and other rows being retrieved as needed.
>
> If it turns out that there are good reasons for it to all be in memory, then
> my question is whether there is a better approach that people typically use
> in this situation. For now, I'm simply breaking up the select into smaller
> chunks, but that approach won't be satisfactory in the long run.
>
> Thanks
>
> -Nick
>
> --------------------------------------------------------------------------
> Nick Fankhauser nickf(at)ontko(dot)com Phone 1.765.935.4283 Fax 1.765.962.9788
> Ray Ontko & Co. Software Consulting Services http://www.ontko.com/
>
>
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