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How to order elements when accesed by many to many relation in pythons SQLAlchemy?

Assuming two models in a many to many relationship:

parent_child = Table('parent_child', metadata,
                         Column('parent_id', Integer, ForeignKey('parent.id')),
                         Column('child_id', Integer, ForeignKey('children.id')))

class Parents(Base):
    __tablename__ = 'parents'
    __table_args__ = {'autoload' : True} # reflecting database

    children = relationship('Child',
                          secondary=parent_chi开发者_StackOverflowld,  # What goes here for sorting?
                          backref='parents')

class Child(Base):
    __tablename__ = 'children'
    __table_args__ = {'autoload' : True} # reflecting database

I know I can do

parent = session.query(Parent).first()

to get the first parent element in the table. Doing

parent.children

returns all children of the given parent. What if I want to sort them let's say by birthdate (assuming the model Child has column birthdate)?


there's an order_by keyword argument available for relationship. here


Also your missing the s in the parent = session.query(Parents).first() and the s in the ForeignKey

children = relationship('Child', secondary=parent_child, order_by='Child.birthdate', backref='parents')
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