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Multi-user Paradox System

I have a multi-user paradox system that was written in Delphi 5.  I
sporadically encounter a corrupt database file when I get two users
simultaneous insert a record.  What is the optimum way to set up the BDE, to
set up table components in delphi, proper way to code this so that two
records don't end up getting posted at the same time and corrupting the
table, which seems to be what is happening?

Also, is there any real difference in using a table.Insert or a table.Append
in my indexed paradox tables?

Any help or advice would be appreciated.

 

Re:Multi-user Paradox System


Quote
Chris M wrote:

> I have a multi-user paradox system that was written in Delphi 5.  I
> sporadically encounter a corrupt database file when I get two users
> simultaneous insert a record.  What is the optimum way to set up the BDE, to
> set up table components in delphi,

There's only two or three things that must be set correctly, and 97% of
the corruption problems will be solved.

1. Set BDE setting LocalShare = True on all the workstations. This will
   flush all the BDE memory cache contents to hard disk a.s.a.p.

2. Ensure that all the workstations are pointing, and accessing single
   PDOXUSRS.NET file on the shared network drive.

   -Try first deleting all the PDOXUSRS.NET and PDOXUSRS.LCK files everywhere
    you find them.
   -Then start your app on two or more workstations. Now, use Windows Find
    to seek the PDOXUSRS.NET files on all the workstations and servers.
    There should not be more than exactly one instance of it, on the shared
    network drive.

If you are useing TQueries, the third important thing to do is to check
that every user has their own BDE Private Directory set.
The BDE should be pointing the Private Directory setting to a location
of every user's own hard disk, not to the networked drive.

Markku Nevalainen

Re:Multi-user Paradox System


Quote
"Markku Nevalainen" <m...@iki.fi> wrote in message

news:3C11F97A.7573@iki.fi...

Quote
> There's only two or three things that must be set correctly, and 97% of
> the corruption problems will be solved.

4. Make sure that OportunisticLocking is turned off on the server and
DiscardCacheOnOpen is enabled on the workstations.

5. Make sure that IPX/SPX is not installed as a protocol on any of the
involved machines if the server o/s is a flavor of Windows.

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