The relational data model is first order or propositional logic, and set theory. It's math & logic. It is intrinsic to computer science, since Codd's foundation

The relational data model is first order or propositional logic, and set theory. It's math & logic. It is intrinsic to computer science, since Codd's foundational papers. SQL itself is full of problems, but the foundations behind it are definitely not; database theory and database internals is one of the deepest domains of computer science, up there with operating systems. And dismissing this knowledge as "trade school course"work is... sad.