How do you corrupt a CDX?

[GKatReliable]

We have a commercial payroll application written in FPW26a.
I support it, and we have been running it for a decade.
Only recently have I encountered problems with a couple .Dbf's where as soon as the command to USE the file ORDER 1 is invoked, BAM! they get an error Record out of range. I have to rebuild the index tags in the CDX, and that allows our users to proceed.
Since this is a recent problem here, I want to pin down what is causing it, but I can't think of how I could sit down and deliberately corrupt a CDX. There are many, many .Dbf's in this application, so it's not over-use of one key file.
It is either the users working within the application or the add-on programs we wrote, or some other analyst getting in the files outside of the application software.
Again, if I could get an inkling of what it takes to toast a CDX, I could have a better idea of how to pin down the source of this corruption.

Regards,
Glenn Koproske

 

[JRB-Bldr]

There are a variety of ways that a CDX file can get corrupted.

But one of the most encountered reasons is the a shutting down their workstation while an application is still running with the table in USE.

If this is your problem, you might want to put TIMEOUT's into your READS which would shut down things (including closing data tables) "gracefully" when the user was no longer using the application actively.

While this will not absolutely eliminate the problem, it might very likely significantly reduce its rate of occurance.

Other possible reasons could be related to the network problems.

You say "this is a recent problem here".
You might ask yourself, what has changed recently?
The answer could very likely point to the source of this new problem.

You could do a Keyword Search of this forum to see other postings on similar topics and their recommended solutions.

Good Luck,


JRB-Bldr
VisionQuest Consulting
Business Analyst & CIO Consulting Services
CIOServices@yahoo.com

 

[rgbean]

You might get something from reading Craig's article "Avoiding Table and Index Corruption" at

http://www.craigberntson.com/articles.htm.

Rick

 

[repete]

i assume from your post that

use xxx order 1

causes a problem, but that (for example)

use xxx order 2

works ok ?

check out your index tags and you might find an index filter involved that results in no records being available ?? i think from memory that is what i have encountered in the past. then again, my memory is not always something to be heavily relied on.



hope this helps

Pete Bloomfield
Down Under