EDBCLIENT: Invalid blob handle in record buffer (DbExpress, D2006)

[w***@gmail.com]

Hi,

My program runs at about 200 sites. At a couple of them, I keep
getting this error "Invalid blob handle in record buffer". This error
occurs just now and then, a couple of times per day, but afterwards,
the contents of TEXT fields may get mixed up with those of other
records. Of course, this causes serious problems.

Setup: Delphi 2006, DbExpress TClientdataset, corelab driver, MS SQL
2005 standard. It's basically one table with about 8 TEXT fields of
100 fields total, 2000 records. Changing to varchar(max) does not
help, I presume the problem is on the client, not on the server.

About 10 simulteanous users.

--> I can not reproduce this in a controlled situation.
--> I do not know when EXACTLY the error occurs, e.g. what the user is
doing and which method of the clientdataset is begin invoked. It's a
large system. I'm trying to find out by adding extra logging now.

I'm looking for pointers in the right direction or anyone who has
experienced the same problem. I've found some results on Google but
they're all about a known (Nested dataset) bug in D7 which should be
solved.

Thanks for any reaction.

Willem.

[Willem]

I would also be happy with just an explanation what this error means
and which unit or DLL raises this exception.

Strange how the exact same message can be found in one of the old BDE
units, but nowhere else.

Its type is EDBCLIENT, but I can't find where it is raised in that
unit.

Or does it come from Midas.dll / Midaslib?

Willem.

Post by w***@gmail.com
Hi,
My program runs at about 200 sites. At a couple of them, I keep
getting this error "Invalid blob handle in record buffer". This error
occurs just now and then, a couple of times per day, but afterwards,
the contents of TEXT fields may get mixed up with those of other
records. Of course, this causes serious problems.
Setup: Delphi 2006, DbExpress TClientdataset, corelab driver, MS SQL
2005 standard. It's basically one table with about 8 TEXT fields of
100 fields total, 2000 records. Changing to varchar(max) does not
help, I presume the problem is on the client, not on the server.
About 10 simulteanous users.
--> I can not reproduce this in a controlled situation.
--> I do not know when EXACTLY the error occurs, e.g. what the user is
doing and which method of the clientdataset is begin invoked. It's a
large system. I'm trying to find out by adding extra logging now.
I'm looking for pointers in the right direction or anyone who has
experienced the same problem. I've found some results on Google but
they're all about a known (Nested dataset) bug in D7 which should be
solved.
Thanks for any reaction.
Willem.

[Willem]

My extra debugging showed that the dataset state is dsEdit when the
error occurs.

It would be nice if anyone could tell me when this error is raised.


Willem.

Post by Willem
I would also be happy with just an explanation what this error means
and which unit or DLL raises this exception.
Strange how the exact same message can be found in one of the old BDE
units, but nowhere else.
Its type is EDBCLIENT, but I can't find where it is raised in that
unit.
Or does it come from Midas.dll / Midaslib?
Willem.

Post by w***@gmail.com
Hi,
My program runs at about 200 sites. At a couple of them, I keep
getting this error "Invalid blob handle in record buffer". This error
occurs just now and then, a couple of times per day, but afterwards,
the contents of TEXT fields may get mixed up with those of other
records. Of course, this causes serious problems.
Setup: Delphi 2006, DbExpress TClientdataset, corelab driver, MS SQL
2005 standard. It's basically one table with about 8 TEXT fields of
100 fields total, 2000 records. Changing to varchar(max) does not
help, I presume the problem is on the client, not on the server.
About 10 simulteanous users.
--> I can not reproduce this in a controlled situation.
--> I do not know when EXACTLY the error occurs, e.g. what the user is
doing and which method of the clientdataset is begin invoked. It's a
large system. I'm trying to find out by adding extra logging now.
I'm looking for pointers in the right direction or anyone who has
experienced the same problem. I've found some results on Google but
they're all about a known (Nested dataset) bug in D7 which should be
solved.
Thanks for any reaction.
Willem.- Hide quoted text -

- Show quoted text -