http://code.google.com/appengine/docs/datastore/creatinggettinganddeletingdata.html
class editBlog(BaseRequestHandler):
def get(self):
cmd = self.request.get('cmd')
if cmd == 'delete':
q = db.GqlQuery("SELECT * FROM Blog" )
results = q.fetch(100)
# db.delete(results)
for result in results:
result.delete()
self.redirect('/_ah/admin/datastore?kind=Blog')
# self.redirect('/helloworld/')
Deleting an entity does not change any Key values in the datastore that may have referred to the entity. If your application may attempt to de-reference a Key value for a deleted entity, the application should do so using db.get(), then test the return value before accessing properties.
- get(keys)
- Gets the entity or entities for the given key or keys, of any Model.
- Arguments:
-
If one Key is provided, the return value is an instance of the appropriate Model class, or None if no entity exists with the given Key. If a list of Keys is provided, the return value is a corresponding list of model instances, with None values when no entity exists for a corresponding Key. See also Model.get().
-
Deleting an entity that is an ancestor for other entities does not affect the other entities. As long as the application does not depend on the existence of the ancestor to build keys for the descendant entities, the application can still access the descendants.
ループによる登録が思うように動作しない
トランザクションの問題ではないようなのだが。
http://code.google.com/appengine/docs/datastore/transactions.html
