Hello all.

I have written a piece of software that processes orders for my company,
amongst other things. I use 8 tables.

2 of my tables are Paradox tables, the rest are DBase tables. I am having
trouble with the most important table - a Paradox table which contain
important information regarding order which the company receives and hence
manufactures. The program and tables were functioning perfectly for around
two weeks. All of a sudden I am presented with an error message 'Corrupt
table/index header' when I try to view the table in Database Desktop - and
occasionally it wont let me even view the table.

I first noticed that when I was inserting records into the dataset, its size
was not increasing, simply deleting the first record when inserting a 'last
' record. When I do manage to view the table in Database Desktop, a series
of 'dots' appear in a vertical line instead of field values - amongst other
strange happenings. I am using XP, and the software/tables are not shared
over a network.

Does anyone have any idea why my table should repetitively becoming
corrupt??

Any help would be much appreciated!

John




H.V.C. Supplies (Stourbridge) Ltd.
Tel: 01384 376555
Fax: 01384 392555
www.h-v-c.com
sales (AT) h-v-c (DOT) com

"H.V.C. Supplies (Stourbridge) Ltd." wrote:

you don't say anything about repairing the table, so "repetative" might not
apply.. rebuild the table with the repair tool, pack the table and rebuild the
indexes, and you should be fine..


--
Steven Green - Waldorf Maryland USA

Diamond Software Group
http://www.diamondsg.com/main.htm
Paradox Support & Sales - Corel CTech Paradox
---------------------------------------------------
Diamond Sports Gems
http://www.diamondsg.com/gemsmain.htm
Trading Cards and other Sports Memorabilia
---------------------------------------------------

What do you mean by the repair tool? I have read about the TUtility paradox
repair tool but it doesn't make much sense to me! With regard to packing
the table and rebuilding the indexes, can these be done through code in my
program?

And how do I know when to repair, pack and rebuild the table? Should this
be done at regular intervals or only when the table becomes corrupt? - since
it is difficult to know when the table has become corrupt. I only know that
it is corrupt when I try and view it in Database Desktop.

I really want to be able to leave my users operating this software.

Thanks.


"Steven Green" <greens (AT) diamondsg (DOT) com> wrote

"H.V.C. Supplies (Stourbridge) Ltd." wrote:

why doesn't it make sense?.. from your Delphi perspective, there are a number of
3rd party wrappers that make using it easy.. and/or direct BDE API calls
yourself.. also, there is an excellent product called ChimneySweep that doesn't
use Tutility at all.. there's a link to Sundial on my Links page..


yes..


this should never be an issue.. 99% of all "damaged table" issues are just hosed
indexes.. if you follow the common wisdom to disable Windows Oplocks and
Caching, and Local Share in the BDE is TRUE, this should be a very rare
occurance..

*real* table damage is even rarer.. it will usually point to external failures..
bad power supply, failing drives, bad network cards, etc..

if this is more than a once-in-a-blue-moon situation, something is wrong..


--
Steven Green - Waldorf Maryland USA

Diamond Software Group
http://www.diamondsg.com/main.htm
Paradox Support & Sales - Corel CTech Paradox
---------------------------------------------------
Diamond Sports Gems
http://www.diamondsg.com/gemsmain.htm
Trading Cards and other Sports Memorabilia
---------------------------------------------------

On Wed, 13 Apr 2005 09:59:50 +0000 (UTC), H.V.C. Supplies
(Stourbridge) Ltd. wrote:

TUtility may not have the clearest interface in the computer
world -- but it is pretty simple to use. Run it; tell it what
table to rebuild; that's it. Don't bother with the "verify table"
option, as it doesn't catch all problems. Just rebuild.

Chimneysweep is said to do a much better job, and all the
corporate Paradox users swear by it. I've never needed it for my
3 workstation SOHO. Tutility always worked fine. And, as Steven
said, real corruption is very rare and frequently indicates a
problem external to the application (like a failing hard drive,
faulty network, or user hitting the off switch while Paradox is
open).


Jim Hargan

H.V.C. Supplies (Stourbridge) Ltd. wrote:

It sounds like the header of the table is indeed corrupt, but the fact that
the file-size is not increasing makes me worry first about the /filesystem/
on the disk itself. Have you run ScanDisk (or its equivalent) on this
drive lately? {On XP, the disk verification facility is reached from "My
Computer."}

If the tables are not shared, and are on a modern XP and are not, say, being
accessed by a 16-bit version of Paradox, then the fact that you say that
this "suddenly" started happening and that it is "repetitively" happening
is quite suspect. Do you have a virus-scanner running on the computer?
(If it's scanning "every file, every time," it can cause considerable
interference to a database, besides being totally unnecessary.)

_What_ _changed_ ?

Also note: a Paradox file does not always "constantly increase in size" as
a dBase table does. Paradox does recycle space automatically when records
are removed. If the table undergoes a combination of insert and delete
activity in equal number, the fact that the table does not grow in size is
not /a/ /priori/ an indication of a problem. (The other reported symptoms,
of course, are.)

-----------------------
ChimneySweep(R): Fast(!) table maintenance at a click of the mouse!
http://www.sundialservices.com