Relational Database Management System
Before you can begin to develop applications that access Ingres databases, you must understand some of the basic concepts and functions of Ingres.
Ingres is called a Relational Database Management System (RDBMS) because of the way it handles information. If you break this term up into its individual parts, it becomes much easier to understand:
• A database is a set of related information that Ingres stores for you in a computer. For example, your company has an inventory database of products and orders and a personnel database with information on its employees.
The basic units of information that a database stores are called data.
• Management means that Ingres takes care of storing your data for you. It lets you put data into your databases—to add new customers, for example—or retrieve data from it—to produce a report of all items sold last month, for example.
• Ingres is a system because you can combine its different components to organize and access your data in the way that works best for you. Ingres has a variety of tools for such functions as creating reports, designing forms to make data entry easier, and retrieving data from a database.
• Finally, Ingres is relational because it stores your data in tables that make it easy for you to see how the various pieces of information relate to each other. These tables are illustrated in the next section.