Thanks Nacho. I asked the same question in google appengine chat irc and got the same answer. Will have to use the allocate id feature in low level api.
Len On Oct 21, 7:41 am, Nacho Coloma <icol...@gmail.com> wrote: > Maybe what you are looking for is DatastoreService.allocateIds(). > > On Oct 21, 9:35 am, leszek <leszek.ptokar...@gmail.com> wrote: > > > > > You hit the nail on the head. As far as I know there is nothing like > > "sequence" in Google App Engine. Either you need to have another > > entity with a counter and increase it in transactional way. Or you can > > use memcache. > > >http://code.google.com/intl/pl/appengine/docs/java/javadoc/com/google... > > > There is a method: > > -------- > > java.lang.Long increment(java.lang.Object key, long delta) > > Atomically fetches, increments, and stores a given integral > > value. > > ------- > > > Pay attention to "atomically". May be this can be used for generating > > sequential and avoid bottleneck in the case of datastore entity and > > additional transaction. But because of the risk of memcache expiring > > this method needs some more elaboration.- Hide quoted text - > > - Show quoted text - --~--~---------~--~----~------------~-------~--~----~ 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 -~----------~----~----~----~------~----~------~--~---
