fetch relationship rows sqlalchemy code example
Example: sql alchemy query table and include relationship
# joined-load the "orders" collection on "User"
query(User).options(joinedload(User.orders))
# joined-load Order.items and then Item.keywords
query(Order).options(
joinedload(Order.items).joinedload(Item.keywords))
# lazily load Order.items, but when Items are loaded,
# joined-load the keywords collection
query(Order).options(
lazyload(Order.items).joinedload(Item.keywords))