"If we call +1, -1, and √-1 had been called direct, inverse and lateral units, instead of positive, negative, and imaginary (or impossible) units, such an obscurity would have been out of the question."
With SQL you kind of have two options/extremes that are unpleasant in their own way.
You either model things in a very domain specific and classic fashion. Here you get the benefit of being quite declarative and ad-hoc queries are natural. Also your schema is stronger, as in it can catch more misuse by default. But this kind of schema tends to have _logical_ repetition and is so specific that change/evolution is quite painful, because every new addition or use-case needs a migration.
Or you model things very generically, more data driven than schema driven. You lose schema strength and you definitely lose sensible ad-hoc queries. But you gain flexibility and generality and can cover much more ground.
You can kind of get around this dichotomy with views, perhaps triggers and such. In an ideal world you'd want the former to be your views and the latter to be your foundational schema.
But now you get into another problem, which is that homogeneous tables are just _super_ rigid as result sets. There are plenty of very common types you cannot cover. For example tagged unions, or any kind of even shallowly nested result (extremely common use case), or multiple result groups in one query. All of these things usually mean you want multiple queries (read transaction) or you use non-SQL stuff like building JSONs (super awkward).
If you can afford to use something like SQLite, then some of the concerns go away. The DB is right there so it's fine to query it repeatedly in small chunks.
I wonder if we're generally doing it wrong though, especially in web development. Shouldn't the backend code quite literally live on the database? I wish my backend language would be a data base query language first and a general purpose language second, so to speak. Clojure and its datalog flavors come close. But I'm thinking of something even more integrated and purpose built.
--Gauss