So I’ve just woken up to how hard it really is to do something like join fetch an @Any mapping.

I got some distance with this by mapping the association @Any(fetch=LAZY), and then using a query like this:

select n, p from N n join P p on n.thing.id = p.id

And then as long as I remember to force-initialize n.thing before the tx ends, it essentially works.

There’s three things wrong with this:

1. it’s pretty verbose,
2. I have to explicitly force-initialize the proxies, and
3. if I switch to @Any(fetch=EAGER)(which is the default, ugh) then I start getting n+1 selects.

So, damn, it would sure be nice to be able to write things like:

select n, t from N n join n.thing t

select n from N n join fetch n.thing

select n, p from N n join treat(n.thing as P) p

select n from N n join fetch treat(n.thing as P)

But I would say the highest priority would be to simply fix the problem that fetch=EAGER automatically results in extra unnecessary selects.