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 From: Pete Sass
  Where is Pete Sass?
 Marathon, Ontario
 Canada
 Pete Sass
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Subject: Database, Table and CDX Corruption Issues
Thread ID: 107553 Message ID: 107553 # Views: 139 # Ratings: 6
Version: Not Applicable Category: Databases, Tables and SQL Server
Date: Thursday, September 21, 2006 12:31:05 AM         
   


Hi,

This thread is directed to the several threads of late in the forum on corruption issues
with Visual FoxPro backends.

I have submitted this type of thread before, but feel this needs a review again at this time.

In another thread on this same topic here is what I had to say:

1. You need to ensure that your server that houses the VFP backend has UPS.
2. You need to ensure that you have an ON SHUTDOWN procedure in ALL your applications
to properly shutdown the application in the event any user hits the Ctrl+Alt+Delete
keys while the application is still running.
3. You want to ensure in a multi-user network application you use the "FLUSH" command
after all tableupdate()'s if using a Visual Foxpro backend.

ps... even harder to track is the case where you have one flaky ethernet drop, or a
flaky network card in one computer causing the corruption issue. This is why in all my
VFP multi-user programs I have an error trap that with the firing of an error, I dump to
a log file the logged in user ID, the computer name, and the time and date, along with the
error code, and message.

The above items are those stock items you should in fact include in any application regardless
of the development and programming language. If you do not have these basics in your
network application you are running blind as far as problem resolution.

I have to advise you that the VFP database and especially the CDX files are more prone to
corruption issues that most other database backend. If you code properly, have the correct
things in place in your application that I mentioned, you will not experience any difficulty
in using the stock VFP backend.
However, if you have none of the above in place in your VFP application, you will find that
you could experience corruption issues and have no way to identify the problem.

In my case due to these issues in mid to large VFP applications I move into a SQL-Server
backend as far as my database of choice. Now I have a lot more stability, good backup
capabilities, and excellent security features not found in the stock VFP DBC backend.

As well, using SQL-Server I can now code stored procedures that work 100% in the backend
and do not impact front end application logic flow, or slow downs.

Just a bit of info to think about. On the flip side of all of this I have VFP stock
backends with 30-40 plus users with the steps I have advised to you in production, and
rairly run into a corrupted table, CDX, etc. I also have a new 1 GB network backbone, all
new ethernet drops and mainly new computers (within the past 2-years).


SUMMARY
=======
For those of you who are Visual FoxPro developers and use the stock Visual FoxPro database
backend, please read my comments listed above. Visual FoxPro as a backend I am suggesting to
you right up front is more prone to corruption issues than a lot of other backend. I am also
suggesting to "You" the application developer, if you do nothing within your application to
improve things with some very basic logic that I would include in any application regardless of
the development language of choice, you as setting yourself up for problems.

I am well versed on the VFP backend and all it's pros and cons. I am sure other experts
will add to this thread to enforce the type of things I am talking about here.

Pete from the Great White North. (Only in Canada, ay.) Over and Out ...

ENTIRE THREAD

Database, Table and CDX Corruption Issues Posted by Pete Sass @ 9/21/2006 12:31:05 AM
RE: Database, Table and CDX Corruption Issues Posted by Ken Murphy @ 9/21/2006 2:34:37 AM
RE: Database, Table and CDX Corruption Issues Posted by Emerson Reed @ 9/21/2006 4:02:41 PM
RE: Database, Table and CDX Corruption Issues Posted by JLW Wade @ 9/22/2006 10:22:22 PM
RE: Database, Table and CDX Corruption Issues Posted by ed hardy @ 12/5/2006 8:51:45 PM
RE: Database, Table and CDX Corruption Issues Posted by ed hardy @ 12/1/2006 6:41:51 PM
RE: Database, Table and CDX Corruption Issues Posted by Pete Sass @ 12/1/2006 6:51:42 PM
RE: Database, Table and CDX Corruption Issues Posted by Terry Parkinson @ 7/11/2007 4:31:50 PM
RE: Database, Table and CDX Corruption Issues Posted by Ken Murphy @ 7/11/2007 9:50:09 PM
RE: Database, Table and CDX Corruption Issues Posted by Terry Parkinson @ 7/12/2007 5:01:20 PM
RE: Database, Table and CDX Corruption Issues Posted by Riche Evardo @ 7/11/2007 8:14:00 AM
RE: Database, Table and CDX Corruption Issues Posted by TabzSki Cubita @ 10/25/2007 11:27:02 AM
RE: Database, Table and CDX Corruption Issues Posted by Rudy Hendrawan @ 12/6/2007 7:24:49 AM
RE: Database, Table and CDX Corruption Issues Posted by Ken Murphy @ 12/6/2007 12:31:10 PM
RE: Database, Table and CDX Corruption Issues Posted by Andrea Mariottini @ 12/6/2007 3:00:51 PM
RE: Database, Table and CDX Corruption Issues Posted by Stoycho Stoychev @ 1/24/2008 6:11:10 PM
RE: Database, Table and CDX Corruption Issues Posted by suhas hegde @ 12/6/2007 3:02:19 PM
RE: Database, Table and CDX Corruption Issues Posted by Floyd Reeves @ 4/22/2018 2:22:17 AM
RE: Database, Table and CDX Corruption Issues Posted by Tore Bleken @ 4/22/2018 8:06:34 AM