@NamedNativeQuery with @SqlResultSetMapping for non-entity

Question

I have been using this post as an example. I have a complex join query (simplified here). It returns a subset of values from two tables (and a derived column using CASE). I don\

Answer 1

The @SqlResultSetMapping and @NamedNativeQuery annotations need to be on an @Entity, not on the non-entity POJO.

If the entity is Foo, then add the annotations as follows:

@SqlResultSetMapping(
           name="myMapping",
           classes={
              @ConstructorResult(
                   targetClass=CarLimitDelta.class,
                     columns={
                        @ColumnResult(name="caseCol"),
                        @ColumnResult(name="colA"),
                        @ColumnResult(name="colB"),
                        }
              )
           }
)
@NamedNativeQuery(name="Foo.getCarLimitDelta", 
        resultSetMapping="myMapping", 
        query="...")
@Entity
public class Foo {
  ...
}

Note that the @NamedNativeQuery name is prefixed with the entity name, e.g. Foo.getCarLimitDelta.

Then add the method to the Foo repository:

@Repository
public interface FooRepository extends CrudRepository<Foo, String> {
    List<CarLimitDelta> getCarLimitDelta();
}

Note that the method name, getCarLimitDelta, matches the @NamedNativeQuery name, minus the prefix.