Обсуждение: PostgreSQL data loss

Hi everyone,
  I have a problem with one of my costomers.
I made a program that uses a PostgreSQL (win32) database to save its data.
My customer claims that he lost lots of data reguarding his own clients
and that those data had surely been saved on the database.
My first guess is that he is the one who deleted the data but wants to
blame someone else, obviously I can't prove it.

Could it be possible for PostgreSQL to lose its data? Maybe with a file
corruption? Could it be possible to restore these data?

My program does not modify or delete data since its more like a log that
only adds information. It is obviously possible to delete these logs but
it requires to answer "yes" to 2 different warnings, so the data can't
be deleted accidentally.

I have other customers with even 10 times the amount of data of the one
who claimed the loss but no problems with them.
He obviously made no backups (and claims whe never told him to do them
so we are responsible even for this) though the program has a dedicated
Backup-section.

Any suggestion?

Daniele

In response to BluDes <DESPAMMAMIdarocchi@PERFAVOREtiscali.it>:

> Hi everyone,
>   I have a problem with one of my costomers.
> I made a program that uses a PostgreSQL (win32) database to save its data.
> My customer claims that he lost lots of data reguarding his own clients
> and that those data had surely been saved on the database.
> My first guess is that he is the one who deleted the data but wants to
> blame someone else, obviously I can't prove it.

No, you can't.  You're contract should contain language regarding you
not being responsible for data loss, to protect you from jerks like this.

> Could it be possible for PostgreSQL to lose its data? Maybe with a file
> corruption? Could it be possible to restore these data?

It's possible for any program to lose data, if the hardware fails, if the
user tries to edit files that they shouldn't.  If the user has admin
access to the PostgreSQL box, they can cause data loss.

> My program does not modify or delete data since its more like a log that
> only adds information. It is obviously possible to delete these logs but
> it requires to answer "yes" to 2 different warnings, so the data can't
> be deleted accidentally.

I've actually seen people accidentally hit "yes" twice when they didn't
want to.  Tell him to lay off the coffee.

> I have other customers with even 10 times the amount of data of the one
> who claimed the loss but no problems with them.
> He obviously made no backups (and claims we never told him to do them
> so we are responsible even for this) though the program has a dedicated
> Backup-section.
>
> Any suggestion?

Yes.  Call your lawyer first and see what the laws in your area say
regarding this.  Then talk to your lawyer about making sure your
boilerplate contract covers this kind of thing and protects you from
future incidents.  Take your lawyers advice on how to handle it.

In any event, refuse to ever do any business with him again.  In my
experience, these kinds of customers aren't worth the pennies they pay
you.  Also, refuse to give in.  If you give him anything for free, he'll
never leave you alone.  I have personal experience with these types.

I am not a lawyer ... I just play one on the Internet.

--
Bill Moran
Collaborative Fusion Inc.

On Fri, 2007-01-26 at 15:06, Bill Moran wrote:
> In response to BluDes <DESPAMMAMIdarocchi@PERFAVOREtiscali.it>:

> >
> > Any suggestion?
>

> In any event, refuse to ever do any business with him again.  In my
> experience, these kinds of customers aren't worth the pennies they pay
> you.  Also, refuse to give in.  If you give him anything for free, he'll
> never leave you alone.  I have personal experience with these types.

What Bill said, ++

Scott Marlowe wrote:
> On Fri, 2007-01-26 at 15:06, Bill Moran wrote:
>> In response to BluDes <DESPAMMAMIdarocchi@PERFAVOREtiscali.it>:
>
>>> Any suggestion?
>
>> In any event, refuse to ever do any business with him again.  In my
>> experience, these kinds of customers aren't worth the pennies they pay
>> you.  Also, refuse to give in.  If you give him anything for free, he'll
>> never leave you alone.  I have personal experience with these types.
>
> What Bill said, ++
'
To follow this up from a PostgreSQL company :).

Be plaintative. Tell him that any loss of data should have been covered
by backups and that such losses of data typically happen either by user
error or hardware failure.

For customer service reasons, offer him 1 hour of diagnostics for free
(assuming this is a good customer). Then you can tell him what your
findings are.

If the customer is difficult after this offering I would suggest firing
the customer.

Sincerely,

Joshua D. Drake
Command Prompt, Inc.



--

      === The PostgreSQL Company: Command Prompt, Inc. ===
Sales/Support: +1.503.667.4564 || 24x7/Emergency: +1.800.492.2240
Providing the most comprehensive  PostgreSQL solutions since 1997
             http://www.commandprompt.com/

Donate to the PostgreSQL Project: http://www.postgresql.org/about/donate
PostgreSQL Replication: http://www.commandprompt.com/products/

On 1/26/07, BluDes <DESPAMMAMIdarocchi@perfavoretiscali.it> wrote:
> Hi everyone,
>   I have a problem with one of my costomers.
> I made a program that uses a PostgreSQL (win32) database to save its data.
> My customer claims that he lost lots of data reguarding his own clients
> and that those data had surely been saved on the database.
> My first guess is that he is the one who deleted the data but wants to
> blame someone else, obviously I can't prove it.

I've been working with PostgreSQL since early 7.1 on dozens of
projects and I've had maybe two or three cases of data corruption that
were not explained by hardware failure or something like that (and
even these cases were debatable since I was not in direct control of
the server).  Both of those cases had side effects...the corruption
busted something else which sent immediate red flags that something
was wrong.

I think your customer is CYA.

merlin

On 26 Gen, 22:44, j...@commandprompt.com ("Joshua D. Drake") wrote:
> Scott Marlowe wrote:
> > On Fri, 2007-01-26 at 15:06, Bill Moran wrote:
> >> In response to BluDes <DESPAMMAMIdaroc...@PERFAVOREtiscali.it>:
>
> >>> Any suggestion?
>
> >> In any event, refuse to ever do any business with him again.  In my
> >> experience, these kinds of customers aren't worth the pennies they pay
> >> you.  Also, refuse to give in.  If you give him anything for free, he'll
> >> never leave you alone.  I have personal experience with these types.
>
> > What Bill said, ++'
> To follow this up from a PostgreSQL company :).
>
> Be plaintative. Tell him that any loss of data should have been covered
> by backups and that such losses of data typically happen either by user
> error or hardware failure.

Thankyou all for the support.
I received a private e-mail with some suggestions on how to recover
data and I'll try that, at least to prove we have absolutely nothing to
do with that.

This situation really pissed me off, this program was release one year
ago and no-one ever complained about data loss, not even our clients
who accepted to test our beta versions.

Thanks again,
Daniele

In addition to the other good suggestions, modify you program to record a
plain old text log of dangerous actions confirmed by users. These kinds of
people usually shut up pretty quickly when you tell them the date, time, IP
address of the machine, and login name of the user who did it.

--
Scott Ribe
scott_ribe@killerbytes.com
http://www.killerbytes.com/
(303) 722-0567 voice