Re: Out of memory error on huge resultset

No disadvantage, in fact that is what we would like to do.


setFetchSize(size)  turns on cursor support, otherwise fetch normally

Dave

On Fri, 2002-10-11 at 10:30, Aaron Mulder wrote:
>     What would be the disadvantage of making the JDBC driver use a
> cursor under the covers (always)?  Is it significantly slower or more
> resource-intensive than fetching all the data at once?  Certainly it seems
> like it would save memory in some cases.
>
> Aaron
>
> On 10 Oct 2002, Dave Cramer wrote:
> > 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@ontko.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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