I use queryDSL to get users with some additional data from the database:
public List<Tuple> getUsersWithData (final SomeParam someParam) {
QUser user = QUser.user;
QRecord record = QRecord.record;
JPQLQuery = query = new JPAQuery(getEntityManager());
NumberPath<Long> cAlias = Expressions.numberPath(Long.class, "cAlias");
return query.from(user)
.leftJoin(record).on(record.someParam.eq(someParam))
.where(user.active.eq(true))
.groupBy(user)
.orderBy(cAlias.asc())
.list(user, record.countDistinct().as(cAlias));
}
Although it works as desired, it generates two COUNT () values in SQL:
SELECT
t0.ID
t0.NAME
to.ACTIVE
COUNT(DISTINCT (t1.ID))
FROM USERS t0 LEFT OUTER JOIN t1 ON (t1.SOME_PARAM_ID = ?)
WHERE t0.ACTIVE = true
GROUP BY t0.ID, to.NAME, t0.ACTIVE
ORDER BY COUNT(DISTINCT (t1.ID))
I want to know if it is possible to get something like this:
SELECT
t0.ID
t0.NAME
to.ACTIVE
COUNT(DISTINCT (t1.ID)) as cAlias
FROM USERS t0 LEFT OUTER JOIN t1 ON (t1.SOME_PARAM_ID = ?)
WHERE t0.ACTIVE = true
GROUP BY t0.ID, to.NAME, t0.ACTIVE
ORDER BY cAlias
I did not understand this from the documentation, please give me some directions if possible.
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