On Tue, Apr 24, 2018 at 8:45 AM Gail Badner <gbadner(a)redhat.com> wrote:
Yes, that should work with CriteriaQuery as well. It's a
reasonable
workaround.
If JPA doesn't support this now, is it something that should be supported
in the future?
The problem with defining support for this in the spec is that it is
relying on Hibernate's "SQL function registry" and its `SQLFunction`
contract. I seriously doubt we'd get all the EG members to agree to some
standardization of anything like a `SQLFunction` contract.
I think proposing to add additional functions to the spec as "built-in" is
probably more likely. I can especially see EXTRACT being likely. Maybe
DATEDIFF. Oracle for sure does not support DATEDIFF, but it does support
the EXTRACT-from-INTERVAL approach. Anyone know offhand other databases
which to not define DATEIDFF?
I personally think having DATEDIFF defined as "built-in" is the best option
as the provider can always map that to EXTRACT-from-INTERVAL for Oracle,
etal - its much harder to do that by mapping EXTRACT-from-INTERVAL to
DATEDIFF.