Re: Record locking issue using ODBC from .NET

Please try the 8.2.0100 which would be released soon.
If you are in a hurry, please install the 8.2.0002 version at
http://pgfoundry.org/projects/psqlodbc/ .

regars,
Hiroshi Inoue

> anomatos@freemail.gr wrote:
> Hello there,
>
> I'm using version 8.01.02.00 of the PostgreSQL driver, any ideas?
>
>

> > Hi Antonis,
> > Which version of driver are you using ?
> >
> > regards,
> > Hiroshi Inoue
> >

> > > anomatos@freemail.gr wrote:
> > >
> > > I want to have exclusive read access to a table row, so that if a client
> > > has access to that row, any other client should either wait or get an
> > > error of the type "could not obtain lock on row in relation 'customers'",
> > > depending on the semantics used in the query string(nowait)
> > >
> > > Both clients execute:
> > >
> > > ...
> > > OdbcTransaction ^ transaction = connection->BeginTransaction();
> > > String ^ query = "select * from customers where id = 3 for update nowait";
> > > OdbcCommand ^ cmd = (gcnew OdbcCommand(query, connection, transaction));
> > > reader = cmd->ExecuteReader();
> > > ...
> > >
> > > After the first client locks the record and before he ends the transaction,
> > > the second tries to acquire the lock. As expected an exception is raised,
> > > BUT:
> > >
> > > One would expect that this exception is of type OdbcException explaining that
> > > "the lock cannot be aquired". Instead of this I get a
> > > System::InvalidOperationException which disables my connection for some
> > > reason. However the above exception hosts an inner exception of the desired
> > > type(OdbcException).
> > >
> > > Does anybody have any idea why I get this type of behaviour, why is my
> > > connection closed?
> > >
> > > Thanks a lot in advance, Antonis