Inserting new records with one-to-many relationship in sqlalchemy

Question

I\'m following the flask-sqlalchemy tutorial on declaring models regarding one-to-many relationship. The example code is as follows:

class Person(db.Model):
             


        

Answer 1

You dont need to write a constructor, you can either treat the addresses property on a Person instance as a list:

a = Address(email='foo@bar.com')
p = Person(name='foo')
p.addresses.append(a)

Or you can pass a list of addresses to the Person constructor

a = Address(email='foo@bar.com')
p = Person(name='foo', addresses=[a])

In either case you can then access the addresses on your Person instance like so:

db.session.add(p)
db.session.add(a)
db.session.commit()
print p.addresses.count() # 1
print p.addresses[0] # 

print p.addresses.filter_by(email='foo@bar.com').count() # 1