Trapping duplicate record exceptions

  • Thread starter Thread starter John Dann
  • Start date Start date
J

John Dann

Is there a specific way in ado.net of trapping an attempted (Access)
database update by da.update that would otherwise result in a record
with a duplicated primary key? The exception generated seems to be
OleDbException which isn't a very specific exception to trap, since it
could presumably be generated for other reasons than a duplicate key.

JGD
 
Hi John,

You should check out OleDbException ErrorCode property and Errors
collection - they'll tell you what is the problem. In case you are wondering
why there is a collection of errors - it is because there can be several
errors reported at once.
 
Hi John,

You should check out OleDbException ErrorCode property and Errors
collection - they'll tell you what is the problem. In case you are wondering
why there is a collection of errors - it is because there can be several
errors reported at once.
Click to expand...

Thanks, but it does sound like my only way of specifically catching
Duplicate error exceptions is to catch the condition:

exception.errocode = -2147467249

which seems a little inelegant albeit the only viable approach.

My other observation is that this error condition rejects the updating
of a database by a dataset irrespective of however many rows the
dataset may contain. So an attempt to update a database with a large
multi-row dataset containing just one potentially duplicate value
rejects the whole dataset, I guess the only workaround is to perform
any update just one row at a time. Or have I misunderstood how this
should work?

JGD
 
Hi John,


John Dann said:
Thanks, but it does sound like my only way of specifically catching
Duplicate error exceptions is to catch the condition:

exception.errocode = -2147467249
Click to expand...

Yes, the error is database specific.
which seems a little inelegant albeit the only viable approach.

My other observation is that this error condition rejects the updating
of a database by a dataset irrespective of however many rows the
dataset may contain. So an attempt to update a database with a large
multi-row dataset containing just one potentially duplicate value
rejects the whole dataset, I guess the only workaround is to perform
any update just one row at a time. Or have I misunderstood how this
should work?
Click to expand...

Normally you want all records either to succeed or to fail, so you put the
Update into a transaction and there is no problem.
However, if you want to continue update even if there are errors, you should
implement RowUpdated event and set e.Status accordingle (perhaps to
UpdateStatus.SkipCurrentRow).
 
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