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Hibernate version: 2.17

Mapping documents:

Code between sessionFactory.openSession() and session.close():

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Debug level Hibernate log excerpt:

I have a class

public class TimeAttendance implements Serializable {
private Long timeAttendanceId;
private Employee employee;
private ApprovalStatus approvalStatus;
private Date startTime;
private Date endTime;
...
}

Employee and ApprovalStatus are also classes implementing Serializable.

I want to retrieve TimeAttendance(s) for a particular employee.

public List getTimeAttendances( Long employeeId ) {
List timeAttendances = new ArrayList();

// hibernate query
String hQuery = "from TimeSheet ts " +
"where ts.employee.employeeId = :eid ";

try {
Session session = HibernateHelper.getSession();

Query query = session.createQuery( hQuery );

query.setLong( "eid", employeeId.longValue() );

timeAttendances = query.list();

} catch (InfrastructureException ie) {
System.out.println("TimeAttendanceDAOHibernate.java: ie.getMessage()= " + ie.getMessage());
return timeSheets;
} catch (HibernateException he) {
System.out.println("TimeAttendanceDAOHibernate.java: he.getMessage()= " + he.getMessage());
return timeSheets;
}

return timeSheets;
}


after calling this function as "getTimeAttendances( new Long("77") )",
i expect Hibernate to execute 1 SELECT statement:
select * from time_attendance where employee_id = 77

Hibernate does it but then it start executing select statement for each of the member of the TimeAttendance class which in itself is a class. this is very inefficient as for TimeAttendance class, 8 of its members are also classes.

is there any way to control it? thanks

You can try to set the variable max_fetch_depth = (1 or 2) on your hibernate.cfg.xml file:

<property name="max_fetch_depth">1</property>

Also, on your mapping file, put the value outer-join=true on the associated entity that you would like to see loaded by an outer join.

<many-to-one class="ApprovalStatus" outer-join=true