If the operation was selected to resolve a deadlock, the
Dbc.del method will fail and
throw a DbDeadlockException exception.
The Dbc.del method may fail and throw an exception for errors specified for other Berkeley DB and C library or system methods.
If a catastrophic error has occurred, the Dbc.del method may fail and throw
a DbRunRecoveryException, in which case all subsequent Berkeley DB calls
will fail in the same way.