As far as i can see, HQL works with mapped associations. I want to be able to set criteria on a subclass for an association (where only the superclass is mapped to the class i want to return)

Say I have the following structure :


ClassA
PropertyA

ClassA2 (Inherited from ClassA)
PropertyB

ClassA3(Also inherited from ClassA)
PropertyC


ClassB (has a mapped association to class A)

I want to do something like this :
select ClassB classB from classB where classB.ClassA2.PropertyB = ' '
Notice i only want to fetch ClassA2 objects with the PropertyB criteria.

but how can i specify criteria for the subclass? The class 'ClassA2' is not mapped to ClassB, only ClassA is so only set criteria using 'PropertyA'

If i do this :

'select ClassA from ClassA classA where ClassA.PropertyA = 'something', it will return the correct subclass (either ClassA, A2, or A3)'

it returns me classA, what i want is Class B

Any Ideas? Ive had a look around and cannot seem to find any similar problems.

Update : I can do this with subselects, as i thought originally, but speed is a concern, and true enough it is slow.

e.g.

Select classB from ClassB classB where ClassB.ClassA in (select classA2 from ClassA2 classA2 where ClassA2.PropertyB = "something")

Is there any other way?

Hi.

Did you ever find out a solution for this ?

I have the same problem and solved it by doing a specific join on the subclass:

select classB from ClassB classB, classB.ClassA classA, ClassA2 classA2 where classA.id = classA2.id and classA2.PropertyB = ' '

It works - but I don't find it very pretty.

Regards
Carsten