I have 3 models: A customer account, a service, and a model that represents a customer's subscription to the service. The subscription is essentially:
class Subscription(db.Model): customer = db.ReferenceProperty(Customer) service = db.ReferenceProperty(Service) I have a user interface that allows creating or cancelling a customer's subscription. I want to be able to create a subscription only if an existing subscription does not already exist. I thought that a transaction might be the key, but I can't do a query in transaction unless it is by key or an ancestor query. So I am not sure what to do. Any thoughts? Thanks, Carl -- 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.
