criteria – Page 2 – Tarik Billa

Hibernate Criteria Join with 3 Tables

March 12, 2023 by Tarik

The fetch mode only says that the association must be fetched. If you want to add restrictions on an associated entity, you must create an alias, or a subcriteria. I generally prefer using aliases, but YMMV: Criteria c = session.createCriteria(Dokument.class, “dokument”); c.createAlias(“dokument.role”, “role”); // inner join by default c.createAlias(“role.contact”, “contact”); c.add(Restrictions.eq(“contact.lastName”, “Test”)); return c.list(); This … Read more

JPA2: Case-insensitive like matching anywhere

March 12, 2023 by Tarik

It may seem a little awkward at first, but it is type-safe. Building queries from strings isn’t, so you notice errors at runtime instead of at compile time. You can make the queries more readable by using indentations or taking each step separately, instead of writing an entire WHERE clause in a single line. To … Read more

How to properly express JPQL “join fetch” with “where” clause as JPA 2 CriteriaQuery?

March 10, 2023 by Tarik

In JPQL the same is actually true in the spec. The JPA spec does not allow an alias to be given to a fetch join. The issue is that you can easily shoot yourself in the foot with this by restricting the context of the join fetch. It is safer to join twice. This is … Read more

Hibernate Criteria Restrictions AND / OR combination

February 19, 2023 by Tarik

think works Criteria criteria = getSession().createCriteria(clazz); Criterion rest1= Restrictions.and(Restrictions.eq(A, “X”), Restrictions.in(“B”, Arrays.asList(“X”,Y))); Criterion rest2= Restrictions.and(Restrictions.eq(A, “Y”), Restrictions.eq(B, “Z”)); criteria.add(Restrictions.or(rest1, rest2));

Hibernate criteria: Joining table without a mapped association

February 14, 2023 by Tarik

This is indeed possible with criteria: DetachedCriteria ownerCriteria = DetachedCriteria.forClass(Owner.class); ownerCriteria.setProjection(Property.forName(“id”)); ownerCriteria.add(Restrictions.eq(“ownername”, “bob”)); Criteria criteria = getSession().createCriteria(Pet.class); criteria.add(Property.forName(“ownerId”).in(ownerCriteria)); Update: This actually performs a sub-query instead of a join but it allows you to use Criteria on two entities that do not have a hibernate relationship defined.

How to get distinct results in hibernate with joins and row-based limiting (paging)?

February 13, 2023 by Tarik

You can achieve the desired result by requesting a list of distinct ids instead of a list of distinct hydrated objects. Simply add this to your criteria: criteria.setProjection(Projections.distinct(Projections.property(“id”))); Now you’ll get the correct number of results according to your row-based limiting. The reason this works is because the projection will perform the distinctness check as … Read more

How to get SQL from Hibernate Criteria API (not for logging)

February 8, 2023 by Tarik

Here’s “another” way to get the SQL : CriteriaImpl criteriaImpl = (CriteriaImpl)criteria; SessionImplementor session = criteriaImpl.getSession(); SessionFactoryImplementor factory = session.getFactory(); CriteriaQueryTranslator translator=new CriteriaQueryTranslator(factory,criteriaImpl,criteriaImpl.getEntityOrClassName(),CriteriaQueryTranslator.ROOT_SQL_ALIAS); String[] implementors = factory.getImplementors( criteriaImpl.getEntityOrClassName() ); CriteriaJoinWalker walker = new CriteriaJoinWalker((OuterJoinLoadable)factory.getEntityPersister(implementors[0]), translator, factory, criteriaImpl, criteriaImpl.getEntityOrClassName(), session.getLoadQueryInfluencers() ); String sql=walker.getSQLString();

JPA and Hibernate – Criteria vs. JPQL or HQL

September 29, 2022 by Tarik

I mostly prefer Criteria Queries for dynamic queries. For example it is much easier to add some ordering dynamically or leave some parts (e.g. restrictions) out depending on some parameter. On the other hand I’m using HQL for static and complex queries, because it’s much easier to understand/read HQL. Also, HQL is a bit more … Read more