sqlalchemy easy way to insert or update?

Question

I have a sequence of new objects. They all look like similar to this:

Foo(pk_col1=x, pk_col2=y, val=\'bar\')

Some of those are Foo that exist (i.e. only val diff

Answer 1

I think you are after new_obj = session.merge(obj). This will merge an object in a detached state into the session if the primary keys match and will make a new one otherwise. So session.save(new_obj) will work for both insert and update.