OK I misread. Let me see if I understood your problem correctly. 1. All the consultations will be stored in that table. 2. When you have a Consultation object, you need a `consultation_count` property for the number of consultation for that day.
So, this should work now, according to me: def generate_consultation_id(date): return Consultation.query.filter_by(data=data).count() + 1 class Consultation(Base): ... cid = Column(Integer, default=generate_consultation_id) This should work, according to me. The function is called while adding the id to the database. Reference<http://docs.sqlalchemy.org/en/rel_0_8/core/schema.html#sqlalchemy.schema.Column.__init__> -- Dhruv Baldawa (http://www.dhruvb.com) On Wed, Feb 6, 2013 at 11:47 AM, Sriram Karra <karra....@gmail.com> wrote: > On Wed, Feb 6, 2013 at 11:32 AM, Dhruv Baldawa <dhruvbald...@gmail.com > >wrote: > > > I would do a: > > > > class Consultation(Base): > > __tablename__ = 'consultation' > > > > id = Column(Integer, primary_key=True) > > patient_id = Column(Integer, ForeignKey('patient.id')) > > doctor_id = Column(Integer, ForeignKey('doctor.id')) > > date = Column(Date(), default=MyT.today()) > > > > @property > > def consultation_count(self): > > ''' returns the consultation count for current date ''' > > return self.query.filter_by(date=self.date).count() # the syntax > > might not be correct > > > > c = Consultation.query.get(1) > > print c.consultation_count > > > > This way its computed on the fly and you dont need to store it. > > > > If I read your code correctly this would mean: > > (a) the consultation_count property for all the consutlations that happened > on a given day will be the same value > (b) for a given row this value will keep changing as we insert more records > into the table. > > So this will not work, no? > _______________________________________________ > BangPypers mailing list > BangPypers@python.org > http://mail.python.org/mailman/listinfo/bangpypers > _______________________________________________ BangPypers mailing list BangPypers@python.org http://mail.python.org/mailman/listinfo/bangpypers