depends on the shape of your data. If there are only limited number of books (less than 5000) then you can simply store a key ListProperties, and bulk fetch Book entities at the same time. If it is possible for a user to read more than that, then you shall think about associated entity or relation index entities
unless you are trying to model an owned relationship, don't bother with entity group -- 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.
