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Retrieve joined element using criteria api [message #1219789] Thu, 05 December 2013 19:27 Go to next message
Emanuele Gesuato is currently offline Emanuele Gesuato
Messages: 11
Registered: December 2012
Junior Member
I'm trying to 'translate' the following jpql query using criteria builder.

select p.name, a from Person p left outer join p.address a


in the select clause I want to include the joined entity address.

Using criteria builder api I did this:
	    Person p = new Person();
	    p.setName("person");
	    em.persist(p);

	    CriteriaBuilder cb = em.getCriteriaBuilder();
	    CriteriaQuery<Object[]> cq = cb.createQuery(Object[].class);
	    Root<Person> root = cq.from(Person.class);
	    Join<Person, Address> join = root.join("address", JoinType.LEFT);
	    
	    cq.multiselect(
	      		root.get("name"),
	    		  join
	     		 );
	    
	    
	     TypedQuery<Object[]> q = em.createQuery(cq);
	    
	      List resultList = q.getResultList();


The persisted person doesn't have an address but a left join should return the person and 'null' as address. The jpql query works as expected but using the critera api I got a strange error because eclipse link tries to create the Address entity and complains about the nullability of the primary key.

Am I missing something ?

In attachment you could find a zip with the project with a runnable Main class (jar are not included because it would exceed file size).


This is the error:

[EL Warning]: 2013-12-05 19:56:54.391--UnitOfWork(5232909)--Exception [EclipseLink-6044] (Eclipse Persistence Services - 2.5.1.v20130918-f2b9fc5): org.eclipse.persistence.exceptions.QueryException
Exception Description: The primary key read from the row [DatabaseRecord(
	ADDRESS.ID => null
	ADDRESS.STREET => null)] during the execution of the query was detected to be null.  Primary keys must not contain null.
Query: ReportQuery(referenceClass=Person sql="SELECT t0.NAME, t1.ID, t1.STREET FROM PERSON t0 LEFT OUTER JOIN ADDRESS t1 ON (t1.ID = t0.ADDRESS_ID)")
Exception in thread "main" javax.persistence.PersistenceException: Exception [EclipseLink-6044] (Eclipse Persistence Services - 2.5.1.v20130918-f2b9fc5): org.eclipse.persistence.exceptions.QueryException
Exception Description: The primary key read from the row [DatabaseRecord(
	ADDRESS.ID => null
	ADDRESS.STREET => null)] during the execution of the query was detected to be null.  Primary keys must not contain null.
Query: ReportQuery(referenceClass=Person sql="SELECT t0.NAME, t1.ID, t1.STREET FROM PERSON t0 LEFT OUTER JOIN ADDRESS t1 ON (t1.ID = t0.ADDRESS_ID)")
	at org.eclipse.persistence.internal.jpa.QueryImpl.getResultList(QueryImpl.java:480)
	at it.egesuato.model.Main.main(Main.java:41)
Caused by: Exception [EclipseLink-6044] (Eclipse Persistence Services - 2.5.1.v20130918-f2b9fc5): org.eclipse.persistence.exceptions.QueryException
Exception Description: The primary key read from the row [DatabaseRecord(
	ADDRESS.ID => null
	ADDRESS.STREET => null)] during the execution of the query was detected to be null.  Primary keys must not contain null.
Query: ReportQuery(referenceClass=Person sql="SELECT t0.NAME, t1.ID, t1.STREET FROM PERSON t0 LEFT OUTER JOIN ADDRESS t1 ON (t1.ID = t0.ADDRESS_ID)")
	at org.eclipse.persistence.exceptions.QueryException.nullPrimaryKeyInBuildingObject(QueryException.java:921)
	at org.eclipse.persistence.internal.descriptors.ObjectBuilder.buildObject(ObjectBuilder.java:715)
	at org.eclipse.persistence.internal.descriptors.ObjectBuilder.buildObject(ObjectBuilder.java:688)
	at org.eclipse.persistence.queries.ReportQueryResult.processItem(ReportQueryResult.java:218)
	at org.eclipse.persistence.queries.ReportQueryResult.buildResult(ReportQueryResult.java:144)
	at org.eclipse.persistence.queries.ReportQueryResult.<init>(ReportQueryResult.java:79)
	at org.eclipse.persistence.queries.ReportQuery.buildObject(ReportQuery.java:594)
	at org.eclipse.persistence.queries.ReportQuery.buildObjects(ReportQuery.java:645)
	at org.eclipse.persistence.queries.ReportQuery.executeDatabaseQuery(ReportQuery.java:848)
	at org.eclipse.persistence.queries.DatabaseQuery.execute(DatabaseQuery.java:899)
	at org.eclipse.persistence.queries.ObjectLevelReadQuery.execute(ObjectLevelReadQuery.java:1127)
	at org.eclipse.persistence.queries.ReadAllQuery.execute(ReadAllQuery.java:403)
	at org.eclipse.persistence.queries.ObjectLevelReadQuery.executeInUnitOfWork(ObjectLevelReadQuery.java:1215)
	at org.eclipse.persistence.internal.sessions.UnitOfWorkImpl.internalExecuteQuery(UnitOfWorkImpl.java:2896)
	at org.eclipse.persistence.internal.sessions.AbstractSession.executeQuery(AbstractSession.java:1793)
	at org.eclipse.persistence.internal.sessions.AbstractSession.executeQuery(AbstractSession.java:1775)
	at org.eclipse.persistence.internal.sessions.AbstractSession.executeQuery(AbstractSession.java:1740)
	at org.eclipse.persistence.internal.jpa.QueryImpl.executeReadQuery(QueryImpl.java:258)
	at org.eclipse.persistence.internal.jpa.QueryImpl.getResultList(QueryImpl.java:469)
	... 1 more

  • Attachment: myjpa.zip
    (Size: 2.99KB, Downloaded 21 times)
Re: Retrieve joined element using criteria api [message #1219881 is a reply to message #1219789] Fri, 06 December 2013 14:09 Go to previous message
Amita Mehta is currently offline Amita Mehta
Messages: 7
Registered: May 2013
Junior Member
We are having this same problem.
We are migrating from TopLink to eclipseLink and not using any JPA but just the Expresiion queries and see the "null primary key" error all over our project. The same code worked with TopLink 10.1.3.5
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