我有
class Question(db.Model):
wording = db.StringProperty(required=True)
class Answer(db.Model):
question = db.ReferenceProperty(Question, required=True)
userId = db.IntegerProperty(required=True)
我想
SELECT * FROM Question WHERE Id NOT IN (
SELECT QuestionId FROM Answer WHERE userId = 1)
如何在 GQL 中做到这一点