I have the following set-up
@Entity
@Table(name = "FOO")
@Inheritance(strategy = InheritanceType.JOINED)
@DiscriminatorColumn(name = "FOO_TYPE", discriminatorType = DiscriminatorType.STRING, length = 20)
@DiscriminatorValue("FOO")
public class Foo implements Serializable {
private static final long serialVersionUID = 1L;
@Id
@Column(name = "ID")
@GeneratedValue(strategy = GenerationType.IDENTITY)
private Long id;
@Column(name = "foo_column")
private String fooColumn;
... getters and setters ...
}
@Entity
@Table(name = "BAR")
@PrimaryKeyJoinColumn(name = "BAR_ID", referencedColumnName = "ID")
@DiscriminatorValue("Bar")
public class Bar extends Foo {
@Column(name = "bar_column")
private String barColumn;
... getters and setters ...
}
When I execute the following query in Hibernate 3.6 as JPA provider, everything works as expected(well... as I expect at least), and the result list is populated with all kinds of objects which extend the Foo class:
List<Foo> fooList = em.createQuery("SELECT foo FROM Foo foo WHERE 1=1 AND foo.fooColumn = 'foo' and foo.barColumn = 'bar'");
Notice that I am filtering by barField on the Foo object - and Hibernate is able to sort this out by filtering and populating the appropriate object.
However, when executing the same query using EclipseLink, I recieve the following error:
...
Caused by: Exception [EclipseLink-0] (Eclipse Persistence Services - 2.5.0.v20130507-3faac2b): org.eclipse.persistence.exceptions.JPQLException
Exception Description: Problem compiling [SELECT foo FROM Foo foo WHERE 1=1 AND foo.fooColumn = 'foo' and foo.barColumn = 'bar']
[66, 79] The state field path 'foo.barColumn' cannot be resolved to a valid type.
...
Note: I have read the documentation of EclipseLink and I added a @DiscriminatorColumn and @DiscriminatorValue to the tables specifically.
Then I changed the query to the following - using the TREAT function:
List<Foo> fooList = em.createQuery("SELECT foo FROM Foo foo WHERE 1=1 AND foo.fooColumn = 'foo' and treat(foo as Bar).barColumn = 'bar'");
which now works (under JPA 2.1).
Is it possible to achieve this filtering on child entity without resorting to JPA 2.1 functionality?
