Hibernate Criteria and multiple join

Question

is possible with Hibernate criteria do it?

select A.something, B.something, C.something, D.something
    from  A JOIN B on A.id = B.id_fk
          JOIN C ON B.id = C.id_fk
          JOIN D ON C.id = D.id_fk;

http://stackoverflow.com/questions/8726396/hibernate-criteria-join-with-3-tables Above mentioned link can help you. — Ishwar Pohani, Jan 15 '13 at 07:30

score 18 · Accepted Answer · answered Feb 23 '11 at 18:18

18

I have got exactly the same problem, and was able to resolve it like this:

return criteria.createCriteria(A.class)
               .createCriteria("b", "join_between_a_b")
               .createCriteria("c", "join_between_b_c")
               .createCriteria("d", "join_between_c_d")
               .add(Restrictions.eq("some_field_of_D", someValue));

Note: "b", "c" and "d" in code above refer to attribute names in A, B and C classes, correspondingly (class A has attribute b and so on).

For this solution you don't even need to have lazy and fetch parameters to be set in your A.hbm.xml.

answered Feb 23 '11 at 18:18

mindas

26,463
15
97
154

How about for the following SQL: select A.columnA1, B.columnB1, C.columnC1 from A inner join B on A.fk_id = B.id inner join C on C.fk_id = B.id? – maxhuang Jun 27 '14 at 08:14
Please open a separate question for this. – mindas Sep 12 '14 at 16:44

score 3 · Answer 2 · edited Jul 10 '12 at 17:59

3

There are some good examples in the Hibernate Reference material that show to use setFetchMode to fetch associations with an outer join.

An example is:

List books = sess.createCriteria(Book.class)
.setFetchMode("chapters", FetchMode.EAGER)
.setFetchMode("reviews", FetchMode.EAGER)
.list();

There is also information there about different fetching stragies that may be of use to you.

edited Jul 10 '12 at 17:59

Gray

115,027
24
293
354

answered Feb 12 '10 at 16:05

Rachel

3,691
5
32
32

Actually this didn't work for me, I had to do it like in the answer I have posted. It could be because I had an extra criteria on the `D`. – mindas Feb 23 '11 at 18:19
`FetchMode.EAGER` is deprecated nowadays, use `FetchMode.JOIN` instead. – Tim Büthe Aug 13 '19 at 16:23

Péter Török · Answer 3 · 2010-02-13T13:54:58.277

1

Try setting the fetch mode in your criteria, like:

criteria.setFetchMode(..., FetchMode.EAGER)

This creates a join query. You may find more details here.

edited Feb 13 '10 at 13:54

answered Feb 12 '10 at 14:50

Péter Török

114,404
31
268
329

score 0 · Answer 4 · answered Feb 13 '10 at 14:08

Yes, in fact there are several ways of doing this:

When mapping the association, set its lazyness to false and its fetch mode to join. This will affect all criteria queries.
Use setFetchMode as detailed by the other answers.
Use criteria.createAlias (or createCriteria). This also allows you to further restrict the rows you want joined.

Hibernate Criteria and multiple join

4 Answers4

Linked