Hi - the underlying procedure does contain DML and using the native driver allows this but using the Oracle driver does not. I will continue using the native driver, I just wanted to ensure that there was no possibility of using the Oracle driver. many thanks
The Oracle ODBC driver permits full insert/update/delete/select transactions. On the "Oracle ODBC Driver Configuration" page (accessed via the Windows control panel > ODBC Data Source Administrator) there is a checkbox for "read only". Make sure it is not set.