Dear Swapan Das:
On Tuesday, August 21, 2012 10:02:55 PM UTC-7, SWAPAN DAS wrote:
> On Wednesday, August 22, 2012 1:07:18 AM UTC+5:30, dlzc wrote:
>
> > How can you have the data centrally located, yet
> > expect each new client session to form its own
> > indexes? You'd save lots of overhead if you
> > simply had the full set of indexes already formed,
> > and everyone share those.
>
...
> But my this particular Application is created
> later on which have its own set of index files,
> though uses the common dbfs of the other major
> applications. The issue came when sometimes
> the reports from this application doesn't
> reflects the latest changes, and found to have
> discrepancy occasionally.
Yes, this is the "Windows decides what commit really means, and does it when it feels like it" problem. I think it lies in how Windows handled shared files, with a single "user account". Everyone that accesses a file, has the same permissions, and is the exact same user. So Windows then assumes this one-user-with-many-bodys knows what every body wants written to disk, and they have worked it out between themselves.
> And this is because entries/changes are made
> on the other applications, and INDEX FILES of
> this system doesn't gets updated.... So I
> thought to introduce a FORCED INDEXING each
> time (or at-least have the option to have Force
> indexing with Y/n option) to avoid this
> discrepancy.
It would be a pain, but if you close the dbfs and indexes on the "other applications" after changes, then reopen, the indexes will be reliable.
> I can SHIFT this indexing to local drive,
> but doubt if it helps in speed up....as
> accessing dbfs will be always from server
> only, and that part has to be fast.
I'd recommend trying it. At least you would know.
...
> > > [PS:BTW, I do use SET DELETED ON at the top of
>
> > Small penalty,
>
> You may suggest any workaround for this.....
I don't think it is your problem in this case, AND I believe it is much faster to have the "not deleted" flag in the index.
...
> Since this particular said application is
> on-going project; it will be difficult to
> maintain both clipper and [x]harbour
> versions, when I commit programming
> modifications which are unsupported in
> Clipper 5.01.
If you can show the customer how even the WinXP machines are faster with Harbour, they can retire the Win98 machines. But you cannot show this, if you do not migrate en masse. Your efforts here can save you difficulty into the future.
...
> And yes David, thanks a lot for your concern.
> I have found you always been very helpful in
> these our xbase forums. Really appreciate.
> Would again meet here or any other group as
> per the issue.
Thank you. Rare enough I feel I can offer useful advice...
David A. Smith