I am not a python programmer, but how about this logic? add new field called "consultation_count" to the same table
before every insert to the table: Check if the date field on the last record (you might want to add a timestamp field to get the last record easily) = today's date If yes, then it's the same day- take the consultation count from the last record, increment it by one and create the new record. If No, then it's a start of the new day- set the counter to 1 and create the new record. On Tue, Feb 5, 2013 at 9:58 PM, Sriram Karra <karra....@gmail.com> wrote: > I have a Declarative table defined as follows: > > 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()) > > Each row in this table represents a single consultation instance of a > patient seeing a doctor on a given day. > > I would like an additional attribute called "cid" that should be an > auto-incrementing value representing how many-th consultation it was in > that day. Basically it is an auto-incrementing counter, which gets reset to > 0 at the start of a day (hence not unique, whereas the id will be unique). > No row is ever deleted. > > How do I do achieve this with the least amount of additional database > space? It is trivial to have another table with one column for date and > another column for the total consultations thus far. > > Any help? > > -Karra > > P.S. This is for PRS - an open source patient record system for small > clinics I am developing, and available at: https://github.com/skarra/PRS > _______________________________________________ > 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