But basically I feel that this schema is rigid, not particularly well normalized, and would do well to have constraints such as this one applied in a business logic layer rather than at this level ...

SQL Server has a long list of roles for server, database, and applications that outline things like permissions, data selection and modification, and disk management. Examine how roles play a part ...

PolyBase, a data virtualization feature for SQL Server, allows users to seamlessly query data from various external sources directly using T-SQL (Transact-SQL) without the need for separate client ...