Hi, Thanks for your reply. The category is not related to the group - category holds value like Science/Tech/Music while Group stores value like Teens/Kids/Adult. The reason I have these two fields I want to be able to sort the forum according to category and follow by group. So in the forum object I have (field1, ... fieldN, forumcategoryid, forumgroupid) and forumcategory object (forumcategoryid, field1...) and forumgroup object (forumgroupid, field1...). for small app, I think even without mappedBy annonation in relevant class the application will still work. I just have to tie up everything at app level, any advice?
btw, ive gone through the links u given, but there isnt enough app-like example on one-to-many relationship (only the simple guestbook example) On Tue, Aug 9, 2011 at 5:07 PM, Simon Knott <knott.si...@gmail.com> wrote: > Given that the target GAE datastore should be optimised for reads, since > writes are expensive, normalization of data is by no means the way to go. > > Are Categories and Groups joined in any way? i.e. Has a specific Category > got a set of groups, or the other way around? If not, then storing the > group/category as a property within the Forum seems fine to me. > > I would strongly suggest that you read up on the datastore before > proceeding however - the GAE datastore doesn't really consist of tables. I > would read the following docs in their entirety before doing too much more > work: > > - Datastore Overview - > http://code.google.com/appengine/articles/datastore/overview.html > - Java Datastore Docs - > http://code.google.com/appengine/docs/java/datastore/ > - Objectify Docs - These give a good overview of restrictions and best > practices when working with the datastore > http://code.google.com/p/objectify-appengine/wiki/Concepts?tm=6 > > -- > You received this message because you are subscribed to the Google Groups > "Google App Engine for Java" group. > To view this discussion on the web visit > https://groups.google.com/d/msg/google-appengine-java/-/XdtplUMwmLAJ. > > To post to this group, send email to > google-appengine-java@googlegroups.com. > To unsubscribe from this group, send email to > google-appengine-java+unsubscr...@googlegroups.com. > For more options, visit this group at > http://groups.google.com/group/google-appengine-java?hl=en. > -- 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 google-appengine-java@googlegroups.com. To unsubscribe from this group, send email to google-appengine-java+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/google-appengine-java?hl=en.
