I don't think that's right; absent data is really common and a desirable feature, and ergonomically handling it warrants built-in support. Outer joins inherent

I don't think that's right; absent data is really common and a desirable feature, and ergonomically handling it warrants built-in support. Outer joins inherently require a concept of absence of data, so you'd need a built-in Optional type which would be nullability in all but name. And you'd want lifting of operators on the inner type to the optional type for ergonomic reasons; doing a pattern match for every selection of bar.* where bar is left-joined would be extremely painful. I think you'd end up where you started on the null front. Sum types generally, for columns etc., maybe (pun not intended), but I'm skeptical about complex types in a relational language - structure ought to be represented as relations where possible so that everything else composes.