Hi

I am experiencing a problem with Hibernate whereby a call to the DAO method I have inserted below returns duplicate results. The query should return five unique results, however, the returned list contains five references to the same object. We are currently using Hibernate 3.0.5. The same error occurs when I do a HQL query. Does anyone perhaps know what I am doing wrong? Any help would be appreciated!

I have inserted a copy of the Hibernate mapping file we use below the method.

public List findAfterDate(Date d, String[] batchNumbers){
Session session = HibernateUtil.currentSession();

try {
Criteria criteria = session.createCriteria(EctBatchHistory.class);
criteria.add(Expression.ge("timedate", d));
criteria.add(Expression.ne("description", "Batch(es) successfully created."));
criteria.add(Restrictions.in("batch", batchNumbers));
criteria.addOrder(Order.asc("timedate"));
List results = criteria.list();
return results;
} catch(Exception e){
e.printStackTrace();
return new ArrayList();
}
finally {
HibernateUtil.closeSession();
}
}


<!DOCTYPE hibernate-mapping PUBLIC
"-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">
<hibernate-mapping>
<class name="com.EctBatchHistory" table="hist" schema="dbo" lazy="false">
<id name="timedate" column="timedate" type="date" >
<generator class="assigned"/>
</id>
<property name="resellerId" column="reseller_id" type="integer" />
<property name="description" column="description" type="string" />
<property name="batch" column="batch_id" type="string" />
</class>
</hibernate-mapping>

Thanks!

Hi
This happens with in case you have 1-M or M-M and you are using fetching techniques.
The strategy is to convert all the results set - into Set ( containing unique results ) and then convert back to list.

Khurram Samad

Hi Khurram

Thanks for the reply. We have used that solution for another problem where we had a 1-1 and a 1-M relationship that returned duplicates.

With the current problem we do not have any 1-1, 1-M or M-M relationships defined in the mapping file, yet it still returns duplicates.

Thanks

look at your id and think it through what type="date" means for a id column that most likely contain timestamps ;)