You may be interested in my project "Binate"; I have some incomplete notes at http://canonical.org/~kragen/binary-relations about it, exploring a possible design space in which we might find a more concise and compositional query language. Of course that's not in a host programming language; for that there do exist some things like SQLAlchemy and SQLObject which, as a bonus, can compile the resulting query to SQL. The most popular of these is Django's "ORM", which unfortunately is very limited.