Overview of a Database Management System

Overview of a Database Management System

In following figure we see an outline of a complete DBMS. Single boxes represent system components, while double boxes represent in-memory data structures. The solid lines indicate control and data flow, while dashed lines indicate data flow only.

Since the diagram is complicated, we shall consider the details in various stages. First, at the top, we suggest that there are two different sources of commands to the DBMS:

1. Conventional users and application programs that ask for data or alter data.

2. A database administrator: a person or persons responsible for the structure or diagram
   of the database.

Overview of Database Management System