Support Subquery Exists

Currently kotlin-jdsl does not support the CriteriaBuilder.exists method. An implementation of this method is required.

A function like below code should be implemented in jdsl.

think about what kind of appearance is suitable for jdsl.

– korean 현재 kotlin-jdsl 은 CriteriaBuilder.exists 메소드를 지원하지 않습니다. 이 메소드의 구현이 필요합니다.

아래 코드와 같은 기능이 jdsl에 구현 되어야 합니다.

어떤 모습이 jdsl 에 적합한지 같이 고민해보았으면 합니다.

@shouwn @huisam @pickmoment

CriteriaBuilder builder = entityManager.getCriteriaBuilder();
 
CriteriaQuery<Post> query = builder.createQuery(Post.class);
Root<Post> p = query.from(Post.class);
 
ParameterExpression<Integer> minScore = builder.parameter(Integer.class);
Subquery<Integer> subQuery = query.subquery(Integer.class);
Root<PostComment> pc = subQuery.from(PostComment.class);
subQuery
    .select(builder.literal(1))
    .where(
        builder.equal(pc.get(PostComment_.POST), p),
        builder.gt(pc.get(PostComment_.SCORE), minScore)
    );
 
query.where(builder.exists(subQuery));
 
List<Post> posts = entityManager.createQuery(query)
    .setParameter(minScore, 10)
    .getResultList();

generated SQL

SELECT
    p.id AS id1_0_,
    p.title AS title2_0_
FROM post p
WHERE EXISTS (
    SELECT 1
    FROM post_comment pc
    WHERE
        pc.post_id=p.id AND
        pc.score > ?
)
ORDER BY p.id

[shouwn]

@kihwankim @cj848 2.0.7.RELEASE is released

[shouwn]

@cj848 where(exists(subquery))형태가 딱 좋을 것 같습니다. 👍

— english where(exists(subquery)) is the best form.