Yes similar things are done in hobbes, although with array comprehension syntax instead of SQL. Grouping and joins are done with regular functions. I think that this approach scales better than fitting it all into one query syntax (though I don’t feel strongly about the syntax).

Yes you could say it’s row oriented and not column oriented. It’s possible to arrange data in column vectors, and that does get better performance in some situations. I have some ideas to unify the two approaches (so either layout can be decided, ad-hoc), but need a better approach to dependent types.