Hibernate criteria alias generates innej join which eats query results

Question

I have a DAO that searches objects using criteria.list() that searches Accidents. It should return accidents which:

1) Have type A and accidentAttribs (mapped as collection but there is only one element inside) TITLE = Test

2) All other accidents which are not of type A, even if they doesnt have any attribs

Creating this alias:

 criteria.createAlias("accidentAttribsSet", "accidentAttrib");

makes inner join between two tables and accidents without attributes are not returned..

criteria.createAlias("accidentAttribsSet", "accidentAttrib");
                    criteria = criteria.add(Restrictions.or(

                                    Restrictions.not(Restrictions.eq("type", "A")),
                                    Restrictions.and( Restrictions.eq("type", "A"),Restrictions.eq("accidentAttrib.title", "Test") )
                                    )

                    );

I db I have accidents of type B and they dont have any attributes yet and this query doesnt return them.

Answer 1

An inner join means that only accidents with attributes will be in the result set. You should try to use a left join

criteria.createAlias("accidentAttribsSet", "accidentAttrib", JoinType.LEFT.ordinal());