QueryDSL 4 select + where + exists

Question

Just started using queryDSL at my job. So far I think the syntax is very intuitive.

I need to convert a very simple SQL query to queryDSL, but I don't know what do do with the EXISTS clause.

SELECT * FROM XRDocument document
 WHERE status = 0
   AND EXISTS
     (
       select * FROM XEntity X WHERE X.pid in (11,22,33)
     )
  AND NOT EXISTS
     (
      select * FROM XEntity X WHERE X.pid in (44,55,66)
     )

I have all my Q classes ready. So far this is all I have (pseudo code):

JPAQuery query = new JPAQuery(em);
query.from(xDocument).where(xDocument.status.eq(0))

I read the documentation but there's no ".exists()" method. I also tried using the JDOExpressions class but I couldn't come up with a solution.

Can anybody point me to the right direction?

Answer 1

You could do something like

JPAQuery query = new JPAQuery(em)
    .select(xDocument)
    .from(xDocument)
    .where(xDocument.status.eq(0)
        .and(JPAExpressions.selectOne()
            .from(xEntity)
            .where(xEntity.pid.in(11,22,33)
            .exists())
        .and(JPAExpressions.selectOne()
            .from(xEntity)
            .where(xEntity.pid.in(44,55,66)
            .notExists()));