I wrote:
> Another model that could be followed is expansion of inheritance-tree
> references, which happens early in the planner.
Actually ... if you intend to allow column storage to work with inherited
tables (and if you don't, you'd better have a darn good reason why not),
I think you probably want to do this join insertion *after* inheritance
expansion, so you can join child column stores only to the appropriate
child heap table, and not to the entire inheritance tree.
regards, tom lane