[sqlalchemy] subquery in select statement

Posted by webjunkie on Stack Overflow See other posts from Stack Overflow or by webjunkie
Published on 2010-12-31T01:48:03Z Indexed on 2010/12/31 1:54 UTC
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sqlalchemy

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pylons

Hi guys, I have two tables (albums,pictures) in a one to many relationship and I want to display each albums details with one picture so I have the following query

select albums.name,(select pictures.path from pictures where pictures.albumid=albums.id limit 1) as picture from albums where ...

Now I'm struggling creating this on Pylons with sqlalchemy I tried to do the following

picture = Session.query(model.Picture)

sub_q = picture.filter_by(albumid = model.Album.id).limit(1).subquery()

album_q = Session.query(model.Album, sub_q)

result = album_q.all()

but it creates the following statement displaying the incorrect picture beacuse the table albums is included in the subquery

select albums.name,(select pictures.path from pictures,albums where pictures.albumid=albums.id) from albums where ...

Am I doing it wrong?, is this even possible in sqlalchemy?.

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