Welcome To The Home Of The Visual FoxPro Experts  
home. signup. forum. archives. search. google. articles. downloads. faq. members. weblogs. file info. rss.
 From: Ilya Rabyy
  Where is Ilya Rabyy?
 Fountain Valley
 California - United States
 Ilya Rabyy
 To: Yuri Rubinov
  Where is Yuri Rubinov?
 Philadelphia
 Pennsylvania - United States
 Yuri Rubinov
 Tags
Subject: RE: FPT corruption
Thread ID: 78600 Message ID: 78674 # Views: 2 # Ratings: 0
Version: Not Applicable Category: Databases, Tables and SQL Server
Date: Thursday, October 06, 2005 6:59:35 PM         
   



> > > You may review the file structures as they are in VFP help to get more on this.
> >
> >
What section? I haven't seen the description of the DBF's header since the printed Programmer's Guide for FoxPro 2.6.
>
> In VFP9, go to HELP-->Index-->File Structures
> >

Found it, thanks!

> > I never heard about experiments like you did, and I cannot imagine the situation when it is needed.
> > >
> >
It is very simple to imagine, actually: first portion of data (in DBF/CDX/FPT files) is sent to another location (i.e. customer, or another branch) on a CD or DVD and copied over onto an HDD; next time, another CD/DVD with daily (weekly, monthly) data for appending. Operator changes attribute for DBF but forgets (or doesn't know) to do so for CDX and FPT...
>
> So, it is not needed; it was operator mistake.
>
>
Needed it is. As my co-worker says: "You can make it fool-proof, but you can't make it idiot-proof." However, as a Corporate Lead P/A, I must make it as much fool/idiot-proof as humanly (and then some beyond that) possible. I'm not exaggerrating, BTW.
> > >
> > > > 2. Could it be the cause of FPT corruption that DBF is NORMAL and FPT is READONLY?
> > >
> > > Yes, as you can see.

> >
> > Spasibo, Yuri! I'm gonna put it to the test today.
> >


OK, here are the results:

1. If DBF is NORMAL and FPT is READONLY, opening table in exclusive mode results in error message "Memo file is missing or corrupt".

2. If FPT is changed to NORMAL, table opens in exclusive mode without a glitch.

3. Good news: FPT corruption does not happen!

4. Whether CDX is NORMAL or READONLY seems to have no effect.

Summarizing: this is not the cause of corruption!

(So the mystery remains unsolved (:<) Agents Mulder and Scully, Director Kendall, where are you?)

Regards,

Ilya

ENTIRE THREAD

FPT corruption Posted by Ilya Rabyy @ 10/5/2005 11:39:20 PM
RE: FPT corruption Posted by Yuri Rubinov @ 10/6/2005 3:04:56 PM
RE: FPT corruption Posted by Ilya Rabyy @ 10/6/2005 5:41:40 PM
RE: FPT corruption Posted by Yuri Rubinov @ 10/6/2005 5:56:56 PM
RE: FPT corruption Posted by Ilya Rabyy @ 10/6/2005 6:59:35 PM