`C` has some intriguing aspects to it. `projection` (unlike *) allows access to the contained data structure in queries. Make you wonder why we don't support this by default.

Defining columns inline with inferred types makes up for some of the boiler plate of the additional case class.

Shape mapped case classes basically allow the same like `<>` but also allow nesting.

Maybe we should consider a revised or alternative Table class, which (type-wise) requires something like `projection` by default instead of `*`.