Hi

I'm using Delphi7+dbIsam 4.21 ( not c.s. mode )

My clients have a problem...

electric power fall.

Every time database corrupt ! Every Time ! Every Time.


Are there any hint for to diminish this problems ?


Windows XP , Harddisk write cash disabled ?  dbisam property ?


tnx.

> Are there any hint for to diminish this problems ?
c/s mode + UPS on server.
OR
non c/s mode + UPS on every computer.

There's no other way, IMO.

Michael

Antony,

<< I'm using Delphi7+dbIsam 4.21 ( not c.s. mode )

My clients have a problem...

electric power fall.

Every time database corrupt ! Every Time ! Every Time.

Are there any hint for to diminish this problems ? >>

Call the TDBISAMTable and/or TDBISAMQuery FlushBuffers method after any Post
or Delete operation.  That will ensure that the data is flushed to the hard
drive via the OS after any modifications and should cut down on incidences
of corruption.

--
Tim Young
Elevate Software
www.elevatesoft.com

Tim Young [Elevate Software] wrote:
> Call the TDBISAMTable and/or TDBISAMQuery FlushBuffers method after
> any Post or Delete operation.  That will ensure that the data is
> flushed to the hard drive via the OS after any modifications and
> should cut down on incidences of corruption.

And make sure you client uses the NTFS file system instead of FAT.
Journaled file systems are much more robust against file corruptions.

Jan Derk

> Call the TDBISAMTable and/or TDBISAMQuery FlushBuffers method after any
Post
> or Delete operation.  That will ensure that the data is flushed to the
hard
> drive via the OS after any modifications and should cut down on incidences
> of corruption.

Is there a global method , only one for all my application ( for all
TDBISAMTable  ) ?

Antony Miller wrote:

> Hi
>
> I'm using Delphi7+dbIsam 4.21 ( not c.s. mode )
>
> My clients have a problem...
>
> electric power fall.
>
> Every time database corrupt ! Every Time ! Every Time.


you can solve this by Caching the data and closing the database table.
I do this by using ClientDataSets.  I can unplug the server and still
save the work locally. if the client machine goes down I only lose the
work that is open. The database is intact.  This will work for C/S or
non/CS. Other then that you will need to use C/S edition to keep your
database intact if the client goes down.

> you can solve this by Caching the data and closing the database table.
> I do this by using ClientDataSets.  I can unplug the server and still
> save the work locally. if the client machine goes down I only lose the
> work that is open. The database is intact.  This will work for C/S or
> non/CS. Other then that you will need to use C/S edition to keep your
> database intact if the client goes down.

My application is very big..... and complex.


This hint is too expensive and too long like work.

Also make sure to tell your client that their employees should not
start a database operation (Insert, Update, etc.) and then walk away
from their computer, leaving the record "dirty". There's much more of a
chance of corruption if the record is "dirty".

--
Regards,
Jan Ferguson


Antony Miller wrote:

> Hi
>
> I'm using Delphi7+dbIsam 4.21 ( not c.s. mode )
>
> My clients have a problem...
>
> electric power fall.
>
> Every time database corrupt ! Every Time ! Every Time.
>
>
> Are there any hint for to diminish this problems ?
>
>
> Windows XP , Harddisk write cash disabled ?  dbisam property ?
>
>
> tnx.

Antony

Hi Anthony,

I have this same problem with one client (friend), using a custom made
software I built for them. This occurs when they have a edit/insert open,
and the power goes out. One thing I was going to do to get around the
problem (which I haven't done yet... tut tut), was to wrap any inserts /
edits into a transaction.

This way, the table doesn't get accessed with any writing until you commit
the transaction. Instead of getting datacorruption on a power failure every
time, you would only get one if the power went out right in those few
milliseconds when the transaction is posted. (I like those odds much better


However, as already suggested - a UPS (even a cheap one) may be a quick
simple solution.

Cheers

Adam.

"Adam H." <ahairsub4@rREMOVEMEspamSTOPPER.jvxp.com> wrote in message
news:87B1FE9D-8A23-4688-90D9-6833839DEC99@news.elevatesoft.com...
> Hi Anthony,
>
> I have this same problem with one client (friend), using a custom made
> software I built for them. This occurs when they have a edit/insert open,
> and the power goes out. One thing I was going to do to get around the
> problem (which I haven't done yet... tut tut), was to wrap any inserts /
> edits into a transaction.
>
> This way, the table doesn't get accessed with any writing until you commit
> the transaction. Instead of getting datacorruption on a power failure every
> time, you would only get one if the power went out right in those few
> milliseconds when the transaction is posted. (I like those odds much better
>
>
> However, as already suggested - a UPS (even a cheap one) may be a quick
> simple solution.
>
> Cheers
>
> Adam.
>
>

being an Old Main Frame guy I have never understood
this "open record" philosophy, and it has always seemed
a method doomed to result in corruption to me.

Everything I do is transaction based and every site either has
a UPS on the Server or I charge them to repair corrupt data
After the second time paying $300+ to repair corruption
a decent 1000VA UPS for $250 seems real cheap!

gregF