Re: java.lang.OutOfMemoryError

Hello Barry,
  What happen if I call two or more statement with setFetchSize, btw.

   1. setFetchSize 10 for query on table a and table b
   2. select * from a
       select 10 rows from a
   3. select * from b
       select 10 rows from b
   4. I want rows 11-20 from a, now
   5. next 10 rows (11-20) from b

etc

in step 2 'execute' for query table a call 'BEGIN; DECLARE CURSOR  ...'
in step 3 'execute' for query table b call again 'BEGIN; ...'
Can I do this without nested transaction (savepoint)
I think that close in ResultSet or Statement must call 'COMMIT' OR 'ROLLBACK', too

Can You set parametar in driver URL (true or false) that use cursor automagic for true ?

regards
Haris Peco

On Tuesday 04 February 2003 16:42, Barry Lind wrote:
> Paul,
>
> A patch was just applied to cvs head to better deal with this.  The new
> behavior is that by default you get the old behavior, but if you call
> setFetchSize() it will turn on using cursors to incrementally fetch the
> result.
>
> thanks,
> --Barry
>
> PS.  I haven't yet got a new build for the web site, but should in a few
> days, so in the meantime, if you want to try this out, you will need to
> build from cvs sources.
>
> Paul Cullum wrote:
> > I'm querying a table that has nearly 3 million records in it and when I
> > call executeQuery() I get an a java.lang.OutOfMemoryError message.  My
> > immediate thought was that it was strange that a safe fetch size wasn't
> > used automatically so I then I decided to explicitly the fetch size by
> > calling the Connection classes setFetchSize() method.  Apparently this
> > is not implemented in the pg73jdbc3.jar driver.   I am surprised that
> > the default fetch size is so great as to cause an OutOfMemoryError. What
> > is the proper method for using JDBC to query result sets which are
> > potentially large?
> >
> > Thanks,
> > Paul
> >
> >
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