The datastore is schemaless and typeless. If you read an entity that doesn't have a property (empty value), you'll get back a "null". Note that this will be problematic with primitives, so you'll want to use Integer, Long, etc.
On Thu, May 13, 2010 at 3:50 AM, Michael <[email protected]> wrote: > I am working on an application that uses JPA to store certain classes > to the datastore. I was wondering what happens if I add (or remove) > members to the class in a future version of the application. I would > already have data stored with the old properties in the datastore. I > know that the datastore has no problem with different entities of the > same kind having different properties, but how does JPA handle this. > What happens if I read an entity that doesn't have a property that > corresponds to the new member in the new class? What happens if it > has a property for a member that I removed? Does it work differently > with JDO? > > -- > You received this message because you are subscribed to the Google Groups > "Google App Engine" group. > To post to this group, send email to [email protected]. > To unsubscribe from this group, send email to > [email protected]<google-appengine%[email protected]> > . > For more options, visit this group at > http://groups.google.com/group/google-appengine?hl=en. > > -- Ikai Lan Developer Relations, Google App Engine Twitter: http://twitter.com/ikai Delicious: http://delicious.com/ikailan ---------------- Google App Engine links: Blog: http://googleappengine.blogspot.com Twitter: http://twitter.com/app_engine Reddit: http://www.reddit.com/r/appengine -- You received this message because you are subscribed to the Google Groups "Google App Engine" 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?hl=en.
