Many to many relationships aren't natively supported. You have to keep your own set of keys. See http://code.google.com/appengine/docs/java/datastore/relationships.html
Stephen On Jul 31, 10:38 am, Erencie <[email protected]> wrote: > I want to create a many-to-many relationship between Student class and > Course class. The rationale is that one Course contains many Student > objects and one Student object can contain many Course objects as > well. > > @PersistenceCapable(identityType = IdentityType.APPLICATION) > class Student { > ... > > @Persistent > List<Course> courses; > .. > > } > > @PersistenceCapable(identityType = IdentityType.APPLICATION) > class Course { > ... > @Persistent > List<Student> students; > ...} > > Then there is problem when I'm persisting a Student object to the > datastore. I did remember to take care of both sides. > > Can anyone tell me what's going wrong here? -- You received this message because you are subscribed to the Google Groups "Google App Engine for Java" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/google-appengine-java?hl=en.
