We should forget about small efficiencies, say about 97% of the time: premature optimization is the root of all evil.
On Aug 14, 4:21 pm, MK Z <[email protected]> wrote: > 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 <[email protected]> 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 > > [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. -- 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.
