python - SqlAlchemy: Join onto another object -


my little website has table of comments , table of votes. each user of website gets vote once on each comment.

when displaying comments user, select comments table , outerjoin vote if 1 exists current user.

is there way make query vote attached comment through comment.my_vote ?

the way i'm doing now, query returning list each result - [comment, vote] - , i'm passing directly template. i'd prefer if vote child object of comment.

setup model add one-to-one relationship. sample code link verbatim:

class parent(base):     __tablename__ = 'parent'     id = column(integer, primary_key=true)     child = relationship("child", uselist=false, backref="parent",          # lazy='joined', # @note: optional: uncomment have 'child' loaded when parent loaded.     )  class child(base):     __tablename__ = 'child'     id = column(integer, primary_key=true)     parent_id = column(integer, foreignkey('parent.id'))

in case parent comment , child vote.
can query comment, @ same time eagerly loading vote. recomment uncomment commented out line above, query return in 1 sql statement. alternatively can specify loading of vote in query explicitly using joinedload:

res = query(parent).options(joinedload(parent.child))

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