java - UNION to JPA Query

Question

Is it possible to query "UNION" in JPA and even "Criteria Builder"?

I'm looking for examples, but so far i got no result.

Does anyone have any examples of how to use it?

Or would that be with native sql?

question from:https://stackoverflow.com/questions/18958614/union-to-jpa-query

Answer 1

Depending on the case, one could use sub queries, something like:

select e
from Entity e
where e.id in
(
  select e.id
  from Entity2 e2
       join e2.entity e
  where e2.someProperty = 'value'
)
      or e.id in
(
  select e.id
  from Entity3 e3
       join e3.entity e
  where e3.someProperty = 'value2'
)