Re: lock Oracle db objects, but only a lock for others?

Bob Kilmer wrote:

> >expect that the entire code base needs to be rewritten
>
> I agree but this is not practicable. Not only that, without learning
> something, we are likely to write something only a little better or merely
> with different foibles. As it is, I hope to make an admittedly bad situation
> less bad. Can any one address my questions directly? Some of the are yes-no
> questions. Surely someone can manage that.
>
> Bob
>
> "Daniel Morgan" <damorgan_at_exesolutions.com> wrote in message
> news:3EA2DF84.6075EA5_at_exesolutions.com...
> > Bob Kilmer wrote:
> >
> > > Jim,
> > > Thanks for your response. I am new to the app and the company. I didn't
> > > invent the locking and unlocking chaos, I am trying to cure it. I do
> read
> > > the docs online and I will look at what you suggest, but it takes a
> while
> > > for it all to sink in and to find just the right answer and not just a
> > > generic lesson in locking database objects.
> > >
> > > Now that I've finished being defensive, let me say the locking that the
> code
> > > uses is a 'select for update', sometimes with and without a nowait,
> between
> > > a begin trans and commit or rollback. But the code places a lock that
> gets
> > > in its own way! So it commits (or rollsback - who knows - On Error
> Goto!) to
> > > release the lock when it passes control to whatever code it thinks might
> > > need access to the data that it would prefer to remain locked. And that
> code
> > > sets a lock again. (Or should. Or maybe not?) And this happens again and
> > > again as the client opens and closes form after form getting or posting
> > > data, locking and unlocking data, starting and ending transactions,
> before
> > > the finally the process is through.
> > >
> > > Besides all that, the app doesn't really lock all the data up for grabs.
> The
> > > app really just locks a mutually agreed upon row in a particular table.
> This
> > > lock then serves as a flag to other instances of the app not to fool
> with
> > > the data. Not that one couldn't fool with the other data that is not
> locked.
> > > So if all the clients are using this as a flag, they may as well use an
> > > explicit flag, i.e., a flag table value, unless the app can set a
> reasonable
> > > lock that won't get in its own way, don't you think?. Intuition tells me
> > > that this lock, unlock, lock unlock madness is bogus, especially when it
> > > encumbers the code so, and isn't really locking all the data that is
> > > exposed.
> > >
> > > Should the client be using db locking at all?
> > >
> > > Can the client set a legitimate lock that won't get in its own way?
> > >
> > > Would it be just as well to set a flag in a table of flags? (That is, in
> > > effect, what is being done now - except it is a table of real data!)
> > >
> > > Is there another option that is cleaner, easier and more professional
> that I
> > > have yet to discover?
> > >
> > > I would prefer to be able to set a lock or a flag exactly once at the
> > > beginning of a client input or edit process, do the input or editing
> > > machinations, then unlock or lower the flag (once) when I am out of
> there.
> > >
> > > Regards,
> > > Bob
> > >
> > > <snipped>
> > >
> >
> > I'm just guessing based on things in your post but what catches my eye are
> > things like:
> >
> > begin trans
> > On Error Goto
> >
> > If things like this have been written expect that the entire code base
> needs to
> > be rewritten.
> >
> > Daniel Morgan
> >
> >

Then hire someone to train your staff.

I can certainly suggest someone that can fly to where-ever you are and do so.

You will learn more and save money with an on-site instructor for one week or two weeks.

If you are interested in pursuing this option one person I can recommend is Jack Cline. You can email him at jcline_at_deltabravo.net.

Daniel Morgan Received on Sun Apr 20 2003 - 13:34:25 CDT