[sqlalchemy] spanning relationship on 3 tables fails

I have this 4 tables, the base concept is: `sensor data comes from its id_meas / id_cu pair, I can find id_meas directly in data and id_cu in data parent acquisition.` data = Table('data', metadata, Column('id', Integer, primary_key=True), Column('id_acq', Integer,

Re: [sqlalchemy] spanning relationship on 3 tables fails

this is again my error messages not telling the whole story, ill see if i can get the term foreign_keys back in there: mapper(Sensor, sensors, properties={ 'data': relationship(Data, backref='sensor', foreign_keys=[data.c.id_meas],