Search by a property of a reference

Question

I have the following models:

class Station(db.Model):
    code = db.StringProperty(required=True)
    name = db.StringProperty(required=True)

class Schedule(db.Model):
    tripCode = db.StringProperty(required=True)
    station = db.ReferenceProperty(Station, required=True)    
    arrivalTime = db.TimeProperty(required=True)
    departureTime = db.TimeProperty(required=True)

How can I order programatically all the Schedules by Station's name?

Something like Schedule.all().order('station.name')

Answer 1

You will to de-normalize your models or sort the results in memory:

Schedule.all().fetch(100).sort(key=lambda s: s.station.name)

(code not tested)

Answer 2

After use sort i think you need to fetch all entities:

Schedule.all().fetch (100).sort(key=lambda s: s.station.name)

May be you can also use collection name. http://goo.gl/jXEk But i think the jbochi answer is better :)

[x.schedule_set.get () for x in Station.all ().order ('name')]