Query interface for JDOQL queries
Clone the state of the query for the given PersistenceManager
Add the fetch group to the set of active fetch groups.
Set the maximum fetch depth when fetching.
A value of 0 has no meaning and will throw a JDOUserException.
A value of -1 means that no limit is placed on fetching.
A positive integer will result in that number of references from the
initial object to be fetched.