I'm adding a table and subclass table to my DB. (Subclass table = table where the primary key joins to the primary key of another table, to give extra row information to some subset of the rows ...

Foreign keys enforce table relationships, for example (in the case of school enrollments) forbidding you from adding a non-existent student to a class roster, or from deleting a class roster that ...

Real-world relational databases have tables that contain fields, constraints, and triggers, and tables are related through foreign keys. SQL is used to declare the data to be returned, and a SQL ...