Ordering a join fetched collection in JPA using JPQL/HQL

Question

Given the below JPQL statement, how do I modify it so that the kittens in the resulting list are ordered by their age property?

SELECT c FROM Cat c          


        

Answer 1

I am retrieving time intervals with corresponding time slots, and able to order the records using the property of the child collection in the JPQL query.

Following works for me.

SELECT DISTINCT i FROM Interval i INNER JOIN FETCH i.slots s WHERE i.schedulerId = :schedulerId ORDER BY s.startDateTime

Answer 2

Hej,

I don't think this is possible when applied using queries. But as far as I remember, you can use this to add default ordering to your collection in the mapping:

@OrderBy("myColumName asc")

Answer 3

In addition to @bigZee77's answer, you could also perhaps change your query and query for the kitten instead of the cat. The resulting list of kittens would be ordered, and every kitten would point to the same cat:

select k from Cat c inner join fetch c.kittens k where c.id = :id order by k.age

If the cat doesn't have any kitten, you would get an empty list, though.

The alternative is of course to provide a Java method which sorts the list of kittens.