Determining whether a Database is corrupt

[Bungle]

Hi There,

Does anybody know where i might be able to locate a tool/application that
can determine whether a Database is corrupt??

Also, can a bad network connection cause a corruption to a database?

Thanks in advance for any help,

Bungle

[sfdskf';]

Whenever I have a database that can't be repaired using the built in
"compact and repair" menu option, I consider the database corrupt.

Have you tied "compact and repair"?

You might also try creating a blank database and importing the tables
from the corrupt database into the new database (File/Get External
Data/Import).

There are companies who specialize in the recovery of data from
corrupted databases.

I know of one who guarantees 2 hour service, although I have not yet had
the opportunity to try their services.

Yes...a bad network connection might corrupt your database.

Cheers!
Mike

Bungle wrote:

Hi There,

Does anybody know where i might be able to locate a tool/application that
can determine whether a Database is corrupt??

Also, can a bad network connection cause a corruption to a database?

Thanks in advance for any help,

Bungle

[Terrell Miller]

sfdskf'; wrote:

You might also try creating a blank database and importing the tables
from the corrupt database into the new database (File/Get External
Data/Import).

There are companies who specialize in the recovery of data from
corrupted databases.

ironic, since in all likelihood they do *precisely* what you mention,
i.e. they just import all the objects from teh corrupt .mdb and then
rename the copy, ship it off to the gullible client, and charge them a
very nice fee for about seven minutes' work that the client could have
easily done themselves.

:(

--
Terrell Miller
mi******@bellsouth.net

"Every gardener knows nature's random cruelty"
-Paul Simon RE: George Harrison

[Lyle Fairfield]

Terrell Miller wrote:

ironic, since in all likelihood they do *precisely* what you mention,
i.e. they just import all the objects from teh corrupt .mdb and then
rename the copy, ship it off to the gullible client, and charge them a
very nice fee for about seven minutes' work that the client could have
easily done themselves.

Your evidence is ...?

--
--
Lyle

[Tony Toews]

Terrell Miller <mi******@bellsouth.net> wrote:

There are companies who specialize in the recovery of data from
corrupted databases.

ironic, since in all likelihood they do *precisely* what you mention,
i.e. they just import all the objects from teh corrupt .mdb and then
rename the copy, ship it off to the gullible client, and charge them a
very nice fee for about seven minutes' work that the client could have
easily done themselves.

:(

Some may do such. Others get much more detailed and have written their own code to
examine the structure of MDBs.

Tony
--
Tony Toews, Microsoft Access MVP
Please respond only in the newsgroups so that others can
read the entire thread of messages.
Microsoft Access Links, Hints, Tips & Accounting Systems at
http://www.granite.ab.ca/accsmstr.htm

[Terrell Miller]

Tony Toews wrote:

There are companies who specialize in the recovery of data from
corrupted databases.

ironic, since in all likelihood they do *precisely* what you mention,
i.e. they just import all the objects from teh corrupt .mdb and then
rename the copy, ship it off to the gullible client, and charge them a
very nice fee for about seven minutes' work that the client could have
easily done themselves.

:(

Some may do such. Others get much more detailed and have written their own code to
examine the structure of MDBs.

I'm sure they do, but what's the point?

When I was a consultant the senior guy on our team came to me one day.
One of his clients had a corrupt .mdb, he'd been going over it for the
last hour, and he wanted my advice on whether we could reset a registry
entry or recopy a dll or such.

When I told him just to open a blank database, import all the objects
from the corrupt file, delete the corrupt one and rename the new
database, he got *pissed*. Consultants don't do things like that, they
look for excuses to waste several (billable) hours coming up with some
overcomplex solution that makes them look clever.

So he diddled around with the broken .mdb for a long time, then finally
gave up and turned it over to me. It took me all of four minutes to do
precisely what I had suggested in the first place.

Meanwhile the client is sitting there with this "are you guys through
*now*?" glare on his face.

--
Terrell Miller
mi******@bellsouth.net

"Every gardener knows nature's random cruelty"
-Paul Simon RE: George Harrison

[Trevor Best]

Terrell Miller wrote:

sfdskf'; wrote:

You might also try creating a blank database and importing the tables
from the corrupt database into the new database (File/Get External
Data/Import).

There are companies who specialize in the recovery of data from
corrupted databases.

ironic, since in all likelihood they do *precisely* what you mention,
i.e. they just import all the objects from teh corrupt .mdb and then
rename the copy, ship it off to the gullible client, and charge them a
very nice fee for about seven minutes' work that the client could have
easily done themselves.

If they know how to do it. Or it was possible to recover it that way.

I like it when I can charge £500 to change 1 line of code, sounds
ludicrous but here's a breakdown:

Change 1 line of code: £1
Knowing exactly which line to change: £499

;-)

--
This sig left intentionally blank

[lylefair]

I have seen several, perhaps 20, corrupted mdb files. I have restored
some. In none of the cases, did a simple import of all the objects into
a new db effect a complete recovery.
In almost all these cases the db has lost contact with a table; the
pointers to the table are gibberish, or point to gibberish. In this
situation one cannot import the table to another db.
I have had some success with creating a new db and table with the same
structure as the corrupted table, and adding more records than the
corrupted table had, (or a few million when I did not have this
information). The I have done a direct hex copy of the pages from the
corrupted file that seemed to contain the corrupted table's data into
the new table's file. Then I have imported the other "good" objects and
run some code on the repaired table to remove junk records, those that
grabbed bytes that were clearly not legitmate. This seemed to work a
couple of times, but it was not fool-proof and it was very
time-consuming.
At that point I realized that I had never had one of these currupted
dbs myself, being compulsive about backups, and that as it seemed Peter
Miller already had the knowledge I was seeking, I could sleep soundly
at night knowing I could pay his company what seems to me to be a
ridiculously low fee to recover any corrupted mdb I might have.

As you seem to have a magic touch for recovering mdbs perhaps you could
start a recovery business at say 75% of Peter's prices. I dare say if
you were willing to post a performance bond of $500 USD as well you
would get quite a lot of business.

[Tony Toews]

Terrell Miller <mi******@bellsouth.net> wrote:

Some may do such. Others get much more detailed and have written their own code to
examine the structure of MDBs.

I'm sure they do, but what's the point?

When I was a consultant the senior guy on our team came to me one day.
One of his clients had a corrupt .mdb, he'd been going over it for the
last hour, and he wanted my advice on whether we could reset a registry
entry or recopy a dll or such.

When I told him just to open a blank database, import all the objects
from the corrupt file, delete the corrupt one and rename the new
database, he got *pissed*. Consultants don't do things like that, they
look for excuses to waste several (billable) hours coming up with some
overcomplex solution that makes them look clever.

So he diddled around with the broken .mdb for a long time, then finally
gave up and turned it over to me. It took me all of four minutes to do
precisely what I had suggested in the first place.

Meanwhile the client is sitting there with this "are you guys through
*now*?" glare on his face.

<shrug> So that's one data point on the graph. Doesn't count for much.

Tony
--
Tony Toews, Microsoft Access MVP
Please respond only in the newsgroups so that others can
read the entire thread of messages.
Microsoft Access Links, Hints, Tips & Accounting Systems at
http://www.granite.ab.ca/accsmstr.htm

[Terrell Miller]

ly******@yahoo.ca wrote:

I have seen several, perhaps 20, corrupted mdb files. I have restored
some. In none of the cases, did a simple import of all the objects into
a new db effect a complete recovery.
In almost all these cases the db has lost contact with a table; the
pointers to the table are gibberish, or point to gibberish. In this
situation one cannot import the table to another db.
That's why I always push for at least a file-server solution instead of
a single database, actually. Back-ends on a server that's backed up
daily are a lot less corruptible, and a lot easier to recover than
native tables IME.
As you seem to have a magic touch for recovering mdbs perhaps you could
start a recovery business at say 75% of Peter's prices. I dare say if
you were willing to post a performance bond of $500 USD as well you
would get quite a lot of business.

nah, I like app development too much to turn into a utility guy. There
are a lot of people who make good livings writing utilities and classes
and such, more power to them as long as they are actually adding value.
--
Terrell Miller
mi******@bellsouth.net

"Every gardener knows nature's random cruelty"
-Paul Simon RE: George Harrison