I am getting this strange error, and I'm saying strange because I made a change to an unrelated table.
I am trying to query my tDevice
table which looks like this:
class TDevice(Base):
__tablename__ = 'tDevice'
ixDevice = Column(Integer, primary_key=True)
ixDeviceType = Column(Integer, ForeignKey('tDeviceType.ixDeviceType'), nullable=False)
ixSubStation = Column(Integer, ForeignKey('tSubStation.ixSubStation'), nullable=False)
ixModel = Column(Integer, ForeignKey('tModel.ixModel'), nullable=True)
ixParentDevice = Column(Integer, ForeignKey('tDevice.ixDevice'), nullable=True)
sDeviceName = Column(Unicode(255), nullable=False)#added
children = relationship('TDevice',
backref=backref('parent', remote_side=[ixDevice]))
device_type = relationship('TDeviceType',
backref=backref('devices'))
model = relationship('TModel',
backref=backref('devices'))
sub_station = relationship('TSubStation',
backref=backref('devices'))
and this is how I query it:
Device = DBSession.query(TDevice).filter(TDevice.ixDevice == device_id).one()
as soon as this line is executed, I get the error:
ArgumentError: relationship 'report_type' expects a class or a mapper argument (received: <class 'sqlalchemy.sql.schema.Table'>)
The only changes I've made is add a report_type relationship in my tReportTable
which now looks like this:
class TReport(Base):
__tablename__ = 'tReport'
ixReport = Column(Integer, primary_key=True)
ixDevice = Column(Integer, ForeignKey('tDevice.ixDevice'), nullable=False)
ixJob = Column(Integer, ForeignKey('tJob.ixJob'), nullable=False)
ixReportType = Column(Integer, ForeignKey('tReportType.ixReportType'), nullable=False) # added
report_type = relationship('tReportType',
uselist=False,
backref=backref('report'))
device = relationship('TDevice',
uselist=False,
backref=backref('report'))
job = relationship('TJob',
uselist=False,
backref=backref('report'))
I'm still new to SqlAlchemy so I can't seem to see how adding that relationship should be causing this error if I am iterating another table
See Question&Answers more detail:
os