- database.machine_table.c.machine_id==database.machine_access_table.c.machine_id, # join field
- database.machine_table.c.name == machine), # filter field
+ database.machine_table.class_mapper(type(self)).mapped_table.c.machine_id==database.machine_access_table.class_mapper(type(self)).mapped_table.c.machine_id, # join field
+ database.machine_table.class_mapper(type(self)).mapped_table.c.name == machine), # filter field