Check constraints are supported in all of the major DBMS products, including DB2, Oracle, and SQL Server. But they are too-often ignored and not implemented in production databases. Properly defined, ...

The idea of a three-tier DBMS architecture may sound familiar to application developers, but it's not quite the same thing. We'll explain this distinction below. Physical DBMS schema layer Some ...

Referential integrity (RI) is a method for ensuring the 'correctness' of data within a DBMS. People tend to oversimplify RI, stating that it is merely the identification of relationships between ...