When I have a Map inside a TestEntity (mapped either with @OneToMany or @ElementCollection), OpenJPA 2 always performs N + 1 selects when I do the simple query "SELECT z FROM TestEntity z".
A solution to this would of course be great, but I would also be very happy if an OpenJPA developer could quickly try this out and confirm to me whether or not this is indeed an issue with OpenJPA or that it is simply expected behavior. Regards, Henno Vermeulen (p.s. I have tried many settings and the problem occurs no matter what I try. See https://issues.apache.org/jira/browse/OPENJPA-1920 and my unanswered post "preventing N+1 select performance problem on maps").
