Re: Holdable cursors in Oracle?

Holdable cursors may contribute a lot for applications where massive reads are performed followed by successeive store/update operations.

For example - preparing a "cube" for OLAP/ data mining may require massive reads before a single store/update is issued.

While doing this read/update sequence repetaedly - it does make sense to commit the stored/updated data peridically.

But upon commit - cursors would be closed - unless they are holdable. So - without holdable cursors one has to keep track on the cursor position and renew it after every commit.

Yes - data integrity and stability are not maintained - but this is not the issue here.

            Hillel
"Sybrand Bakker" <gooiditweg_at_nospam.demon.nl> wrote in message news:ahgg7von09vo7b1nf0umr8dngj61nu1n8k_at_4ax.com...
> On Wed, 19 Mar 2003 10:09:53 +0000, Billy Verreynne
> <vslabs_at_onwe.co.za> wrote:
>
> >Hillel Eilat wrote:
> >
> >> Some DBMSs support a feature called "Holdable Cursors".
> >>
> >> A holdable cursor is kept open accross transaction boundaries,
> >> as opposed to the 'normal' behavior of most known DBMS's.
> ><snipped>
> >> Is there an equivalent / similar functionaly supported in Oracle?
> >
> >What is the reasoning, functionally and technically, behind such a
concept?
> to avoid parsing
> >How are transactions from different users/sessions handled on this cursor
> >and data integrity guaranteed?
> >
> A cursor exists *within* a session
>
> >And how is this better than treating a table conceptually as a "holdable
> >cursor"?
> >
> >Issues wrt to resource usage are moot IMO. I fail to see how these can
> >dictate a fundemental concept such as holdable cursors.
>
> They aren't. In fact in Pro*C, you can close a cursor and you can
> release it. If you don't release it, and only reevaluate it, you can
> save a parse.
>
>
> >
> >Not all problems are nails. ;-)
>
> Sybrand Bakker, Senior Oracle DBA
>
> To reply remove -verwijderdit from my e-mail address
Received on Thu Mar 20 2003 - 01:28:11 CST