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copied!<p>If I understand the basic premise of the question (admittedly it's a little unclear), it sounds using <a href="http://www.sqlalchemy.org/docs/orm/relationships.html" rel="nofollow">relationships</a> might accomplish this better. From what I'm gathering, a picture has one album, but an album has many pictures? Anyway, that's somewhat irrelevant as the relationship concept is what's important here.</p> <p>You haven't specified how your model is setup, but using <a href="http://www.sqlalchemy.org/docs/orm/extensions/declarative.html" rel="nofollow">declarative</a> syntax you could define the tables like below:</p> <pre><code>class Album(Base): __tablename__ = 'albums' id = Column(Integer, Sequence('album_id_sequence'), primary_key=True) class Picture(Base): __tablename__ = 'pictures' id = Column(Integer, Sequence('picture_id_sequence'), primary_key=True) albumid = Column(Integer, ForeignKey('albums.id')) picture = Column(String(99)) album = relationship('Album', backref=backref('pictures')) </code></pre> <p>Sqlalchemy then takes care of all the hard work for you. Now every 'picture' has an 'album' property, callable via 'picture.album'. In code this looks like:</p> <pre><code>pictures = session.query(Picture).all() for picture in pictures: for album in picture.albums: # do stuff with album </code></pre> <p>And vice-versa, if you have an album, you can get a picture (this is what the backref in the relationship definition does):</p> <pre><code>albums = session.query(Album).all() for album in albums: album.picture # the picture object related to the album </code></pre> <p>I haven't tested the code so chances are there are typos, but hopefully you get the general idea.</p>

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