Hiho

Example: (pseudocode)
class A {String base};
class B extends A {String addon};
Mapped via joined-subclass

Following HQL works:
"select a, a.base, a.addon from A a"

My Problem is, that im not interested into receving all instances of A. I just want a distinct of base + addon.

So i tried something like that:
"select distinct a.base, a.addon from A a"

Hibernate throws no exception, so he thinks that he is able to handle my hql. But my database is not able to work with the resulting SQL, because hib generates faulty wheres (they refer to lacking table aliases).

Is it necessary to include "a" in my resultquery?

Hibernate version: 3.0.5

thx for your Feedback
Bernhard Neuhauser

What about "from B as b" ? That would give you an object, B, that has two strings "base" and "addon".

I know ;o)

But i still want to understand the logic behind hibernate to be able to write more complex queries.

Example:
"select distinct x.a.base, x.a.addon from X x"

My X is a left outer join on another object so it looks more like:
"select distinct x.a.base, x.a.addon from Y y left outer join y.blub.x as x where .. "

So i dont know, how to say ".a" should be from Type B. It seems like hibernate is able to resolve this condition per magic, but only when a will be added to the result.

cybi

I can't see anyway you'd be able to do "select distinct x.a.base, x.a.addon from X x" if X's property is an reference to an A Object. Even if the returned object is the subclass B, the reference is an A and you'd have to cast it before you used properties from a B.