Problem domain = Shopping, Banking, Coffee Shop, Factory, Airplane

Dimension = Customers, Accounts, Users, Widgets, Inventory

Higher-Order Logic = combining basic functional building blocks in order to compose more complex functionality. SQL enables direct, declarative access to the whole space of higher-order functions. E.g. You want the list of widgets made 3 quarters ago but scoped to one factory line, and only when a certain rotation of employees was on the factory floor? You got it. That's like 10-15 lines of SQL.