Can you make a relationship between two tables in a Database Management System DBMS?

Answer 1

Yes, a Database Management System's main advantage is that it will enforce relationships between tables in a database preventing you from entering data in one field in another table that does not already exist in another table. So for example if you have a database that tracks online purchase, the DBMS would prevent a product that does not already exist in the Products table from being added to a shopping cart table. Or an employee ID from being added to a timecard table that does not already exist in the employee table. Databases can be setup without enforced relationships, but doing so usually results in orphaned records (for instance, where and employee id exists in the timecard table that does not exist in the employee table.)