Your first option is what we recommend. App Engine's data model is similar to that of a federated data model based on sharded relational databases. Here's a pretty good session from Google I/O 2009 about migrating to/from RDBMS:
http://code.google.com/events/io/2009/sessions/SofterSideofSchemas.html On Wed, Nov 25, 2009 at 9:40 AM, K.Honsali <[email protected]> wrote: > I would have added > d) use an embedded rdbms, and do own consistency > > If there was a way to control running instances like in EC2.... > > > > On Nov 25, 5:17 pm, "K.Honsali" <[email protected]> wrote: > > Hi all, > > > > If my understanding of previous discussions is correct, we can resume > > from: > > - GAE/J is not relational (not full JDO too), and hence does not > > support sql features such as joins, like, not in ...etc > > - the solution is to de-normalize your tables ... or your mind.. > > > > Now, suppose you have a quite big classic sql-based webapp which is > > multi-layered like a burger, so it is OK to change the Data Access > > Layer without affecting the other components, provided that the DAL > > calls and outputs remain the same. > > If you want to migrate this app to GAE/J, how would you do; knowing > > that beside CRUD queries, you have queries that execute (on the fly w/ > > sql) up to a dozen joins ? > > a ) re-write your DAL in GAE/J's JDO, by denormalizing your tables (& > > your mind) > > b ) write your own sql wrapper, using full JDO and the low level > > datastore (can it be?) > > c ) none of the above > > > > Thanks for your CPU time :) > > -- > > 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]<google-appengine-java%[email protected]> > . > For more options, visit this group at > http://groups.google.com/group/google-appengine-java?hl=en. > > > -- Ikai Lan Developer Programs Engineer, Google App Engine -- 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.
