Sorry if I’m missing something basic and/or pretty obvious but I don’t know how
to model collections of different types/classes.
For example, let’s say I have these base types/classes:
class Chicken(Base):
__tablename__ = ‘chicken'
id = Column(Integer, primary_key=True)
name = Column(Unicode(50))
class Cow(Base):
__tablename__ = ‘cow'
id = Column(Integer, primary_key=True)
name = Column(Unicode(50))
The problem is Old McDonald has multiple barns! So we have:
class Barn(Base):
__tablename__ = ‘barn'
id = Column(Integer, primary_key=True)
name = Column(Unicode(50))
How do we keep collections of “chicken”s and “cow”s in “barn”s?
Let’s say he creates a “Barn 1” row in “barn”. 10 rows from “chicken”s and 10
rows from “cow”s need to associate to the “Barn 1” row in “barn”. And then
later another set of chickens and cows will need to be associated with a “Barn
2".
So a “barn” row is our container that holds our collections.
Also, I think what’s causing some confusion is that a “chicken" or “cow" row
can be associated with more than 1 “barn" at a time. They’re picky that way and
like a change of scenery from time to time.
So maybe given the fact that “chicken” or “cow” rows can be associated more
than 1 “barn” at a time, does this mean I’ll need to setup a many-to-many
relation? And make sure I get the “relationship” call configured correctly on
those referring columns?
Thanks for any help or guidance.
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