sqlalchemy, select using reverse-inclusive (not in) list of child column values

Question

I have a typical Post / Tags (many tags associated with one post) relationship in flask-sqlalchemy, and I want to select posts which aren\'t tagged with any tag in a list I prov

Answer 1

Pretty straightforward using negated any:

query = session.query(Post).filter(~Post.tags.any(Tag.name.in_(['dont', 'want', 'these'])))