Oh, also db.Query takes a class not a string, should be:
db.Query(Article, projection=('title',)).get()On Tue, Apr 24, 2012 at 9:09 PM, Alfred Fuller <[email protected]> wrote: > ('title') is not a tuple, you need to use ('title',) or ['title'] instead > > >>> print ('title') > title > >>> print ('title',) > ('title',) > >>> > > On Tue, Apr 24, 2012 at 8:58 PM, Sun Jing <[email protected]> wrote: > >> I tried to use projection queries: >> >> class Article(db.Model): >> title = db.StringProperty(required=True) >> # others... >> >> print db.Query('Article', projection=('title')).get() >> >>> Traceback (most recent call last): >>> File >>> "/base/python_runtime/python_lib/versions/1/google/appengine/ext/admin/__init__.py", >>> line 331, in post >>> exec(compiled_code, globals()) >>> File "<string>", line 3, in <module> >>> File >>> "/base/python_runtime/python_lib/versions/1/google/appengine/ext/db/__init__.py", >>> line 2098, in get >>> results = self.run(limit=1, **kwargs) >>> File >>> "/base/python_runtime/python_lib/versions/1/google/appengine/ext/db/__init__.py", >>> line 2061, in run >>> raw_query = self._get_query() >>> File >>> "/base/python_runtime/python_lib/versions/1/google/appengine/ext/db/__init__.py", >>> line 2446, in _get_query >>> kind = self._model_class.kind() >>> AttributeError: 'str' object has no attribute 'kind' >> >> >> print db.GqlQuery("SELECT title FROM Article").get().title >> # this one works >> >> -- >> 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. >> > > -- 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.
