Hi, thanks, Long works. and thanks for the info with the search.
so changing the fields of persistent objects later, included big update process. is there no way to change the DB and all its entries directly within the admin console or something like this ? kr Matthias On 26 Apr., 20:19, Timofey Koolin <[email protected]> wrote: > if you want search by value of new property you must resave each > object with new schema. > > On 26 апр, 17:10, Matthias Koch <[email protected]> wrote: > > > > > > > Hi, > > I'm new to appengine. > > and have the first problem hopefully someone can help me. > > > I have just a simple Entiy class like this: > > > @Entity > > public class GuestbookEntry { > > > @Id > > @GeneratedValue(strategy = GenerationType.IDENTITY) > > private Key key; > > private String username; > > private String message; > > ...... > > > } > > > this class will be persisted with jpa. > > > this works fine so far. > > but know I will update this class and add a new field: > > > private long time; > > > when I now start the app and will get the data that is allready stored > > I allways get this error: > > > java.lang.NullPointerException: Datastore entity with kind > > GuestbookEntry and key GuestbookEntry(1) has a null property named > > time. This property is mapped to > > net.umbella.appengine.services.guestbook.model.GuestbookEntry.time, > > which cannot accept null values > > > normaly I would update the db schema by myself, andi can add a default > > value 0 to all existing entry. > > > but how do I solve this problem on appengine ? > > > thanks > > > kindest regards > > Matthias > > > -- > > 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 > > athttp://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 > athttp://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.
