Why Use a Database?

Database-backed applications use databases in very specific ways. They do all the input, processing, and display in the application. They use the database to store information that must be kept after the application exits and information that must be shared with other applications. In summary, the application does its own:

• Input
• Processing
• Display

and relies on the database for:

• Permanent storage
• Sharing information

For example, once an application commits a query, all users can see its changes. Also, when the application exits, all information remains stored in the database.

Of course, a database is not required to permanently store or share information. Information can be stored permanently in flat files and a shared memory area can be used to share information among applications. However, databases make this much easier, and have features like transactions, indexing, joins, aggregates, and a table structure that makes the job of the application programmer easier.