Hi,

When the query cache is enabled, are hibernate queries involvin new'd typesafe objects cached?

i.e. if i have a query like so


select new domain.TopCustomer( member.name, member.purchasePower ) from domain.Member member where member.purchaseHorizon = 3 and member.purchasePower > 2

and i have the query cache enabled and the query set to cacheable, would new'ly created TopCustomer objects also be cached?

The query cache doesn't cache objects, only row ids. And as there are no row ids resulting from your query, nothing will get cached.

slight correction: the query cache only caches the ids relating to entity returns.

This is not an entity return, but a scalar return. The results here will in fact be cached.

Cunning. I think I can make use of this new tidbit to optimize quite a few small-entity queries I have. If I "select new MappedClass(param1, param2...)", does Hibernate get excessively smart and realize that MappedClass is an entity? Because if Hibernate doesn't, and the objects (that are entities) are cached in their entirety, certain report-style queries returning small entities ("type" objects, mostly) can be cached quite efficiently using this technique..

No, only the scalar values are cached (i.e. the simple properties) and the object "wrapper" rebuilt when pulled from the cache.