A relational database management system (RDBMS) is a program that lets you create, update, and administer a relational database. An RDBMS takes Structured Query Language (SQL) statements entered by a user or contained in an application program and creates, updates, or provides access to the database.
Relational database example
Here's a simple example of a relational database:
Your company needs a better way of keeping track of customers, products, and orders because your paper-based system just ain't cutting it anymore. One way of setting this up using the relational model is to create three tables: Customers, Products and Orders.
You can see that the Customer table doesn't care about orders or products, this keeps it focused on its objective - customers. Likewise, the Product table cares only about itself. The Order table uses the ' CustomerID ' and the ' ProductID ' to relate a product to a customer based on an order.