Hi,

a common situation: I have an entities Person and Payment, and I need to show the user a table with all persons and their total payments. In SQL it is SELECT p.*, sum(pay.value) FROM Person p, Payment pay WHERE ... So far, I am aware of several solutions by Hibernate, but I do not know, which one is the best. I need it especially for the criteria query (to be able to sort or filter persons by the total payments.)

Solutions:

1. DV view or @Subselect - I must define more entities for the same table, it might be tedious and cause more coding errors, when some columns are changed. The @MappedSuperclass may help with the coding. But still it is not optimal.

2. @Formula: cons: it is evaluated even when I do not need it.

3. LAZY @Formula using build time instrumentation or Pawel Kepka's trick: http://justonjava.blogspot.com/2010/09/lazy-one-to-one-and-one-to-many.html: Cons: if there are more @Formula fields and just one is hit (needed), all of them are loaded.

4. @MappedSuperclass and @Formula: like solution 1., just instead of DB view, one entity has @formula, the other one doesn't.

5. @Transient property and ResultTransformer: cons: tedious coding, refactoring more difficult.

What's the recommended solution for such situation?
Thanks
Andy