On Wed, Sep 16, 2015 at 8:38 PM Gail Badner <gbad...@redhat.com> wrote:
> Is the only JPA-compliant way to do a multi-level fetch join to use entity > graphs? > > JPA 2.1 does not support fetch joins using an alias at all. JSR 338, > 4.4.5.3 Fetch Joins says, > > "It is not permitted to specify an identification variable for the objects > referenced by the right side of the FETCH JOIN clause, and hence references > to the implicitly fetched entities or elements cannot appear elsewhere in > the query. " > > (I know that HQL supports using an alias for nested fetch joins. [1][2]) > > Also in JSR 338, 4.4.5.3 Fetch Joins is: > > fetch_join ::= [ LEFT [OUTER] | INNER ] JOIN FETCH > join_association_path_expression > > If I understand correctly, the definition of > join_association_path_expression does not allow for join fetching a nested > association using a path, as in: > > select c from Cat c join fetch c.father join fetch c.father.mother <= not > supported by JPA or HQL > > (There is an open Jira for supporting nested join fetches using HQL: > HHH-8206. [3]) > > Is there a JPA 2.0-compliant way to do this (without entity graphs)? > > Thanks, > Gail > > [1] > > http://docs.jboss.org/hibernate/orm/4.3/manual/en-US/html_single/#queryhql-joins > [2] > > https://docs.jboss.org/hibernate/orm/5.0/userGuide/en-US/html_single/#d5e1869 > [3] https://hibernate.atlassian.net/browse/HHH-8206 > _______________________________________________ > hibernate-dev mailing list > hibernate-dev@lists.jboss.org > https://lists.jboss.org/mailman/listinfo/hibernate-dev > _______________________________________________ hibernate-dev mailing list hibernate-dev@lists.jboss.org https://lists.jboss.org/mailman/listinfo/hibernate-dev
