[vog]

> I think constraints vs flexibility is always a tradeoff.

Well, that depends on the application. In the applications I have in mind, I have to make tradeoffs in the opposite direction: I know that some more constraints make totally sense. But: Is it worth implementing them, considering how hard it is to express them in the database?

So I have to make tradeoffs between missing constraints and ease/feasibility of implementation. Or checking some constraints only in the application layer, but sometimes it's even more cumbersome there, than with triggers/etc. in the database.