Re: JDBC 2 ResultSet and cursors

I am afraid I do not understand your explanation. What do you mean by
"begin/end block"? I am thinking in terms of simple SQL statements like:

begin;
declare myc cursor for select * from mm_history;
fetch forward 2 in myc;
close myc;
rollback; (or if you did some update in the same transaction: commit;)

> -----Original Message-----
> From: Joseph Shraibman [mailto:jks(at)selectacast(dot)net]
> Sent: Tuesday, October 16, 2001 11:54 PM
> To: Kovács Péter
> Cc: pgsql-jdbc(at)postgresql(dot)org
> Subject: Re: JDBC 2 ResultSet and cursors
>
>
> Because the driver would have to dedicate a connection to the
> backend to the resultset to
> make sure nobody else tries to begin/end a block while it is
> trying to use a cursor.
> (that's the simple explanation) Since a connection to the
> backend currently requires a
> fork, it would be a real resource hog.
>
> Kovács Péter wrote:
>
> > Hi,
> >
> > I have a question for which I can think of an answer, but still I am
> > uncertain about it.
> >
> > Why the scrollable result sets are not implemented in the
> current jdbc
> > driver? Is it technically impossible or just no one needed
> this feature yet?
> >
> > The answer is probably that due to the lack of backend
> support for updatable
> > cursors the scrollable result set would not be fully
> functional. (On the
> > face of it, I think that it should be possible to build support for
> > read-only scrollable result set into the jdbc driver.) But
> would a halfway
> > solution not be better than nothing? You need to resort to
> workarounds
> > anyway, if you want to use cursor based data processing
> with PostgreSQL.
> > IMHO, a read-only scrollable result set would definitly be
> an important step
> > toward code portability.
> >
> > Any comments?
> >
> > Does anyone have info on whether there are plans to
> implement support for
> > updatable cursors in the backend? If there are, what are they?
> >
> > Thank you
> >
> > Peter
> >
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>
> --
> Joseph Shraibman
> jks(at)selectacast(dot)net
> Increase signal to noise ratio. http://www.targabot.com
>