Information systems keep track of facts about a particular enterprise or business. These facts are used to produce a wide variety of output, providing management with vital data on which to base decisions. Therefore, it is important to implement a design that provides accurate and reliable information.
The design of a database determines the way data is stored and how different types of data relate. Regardless of the size of your database, the design should always be completed before you start building your database.
Although R:BASE is a powerful and easy-to-use tool, R:BASE can't design a database. Designing requires someone with an understanding of both the information that needs to be managed and the principles of database design that are covered in this lesson.
After you determine exactly what information needs to be stored and how it is to be retrieved, you're ready to design your database. The more carefully you design, the more effectively the database will meet your user's needs.
What can happen if a database is poorly designed?
•Data might be unreliable or inaccurate
•Performance might be decreased
•Flexibility might be lost
Any of these problems can cause confusion or even inaccuracy for whomever uses your database. At the least, valuable time will be wasted as you attempt to use a system that is inefficient.
Although there are a number of rules you can follow in designing a database, the design process is only partly scientific; it also involves a degree of creativity that becomes more apparent once you have followed the design process a couple of times. You should follow these rules when at all possible, but not to the point where the database can't deliver the information and functions the user needs.
Begin by sketching a design on paper. There are advantages to creating a paper design first. Mainly, a paper design will help you see potential problems before you begin defining the database.
The first step is to identify the problem. SkyWrite's problem is that the existing manual system cannot keep track of all their customers and provide necessary information in a timely manner. SkyWrite needs a central location where their data can be stored and retrieved quickly.
Some of the facts they need to track are:
•How often a customer uses their services
•Amount of income on a given day
•Seasonal information such as the average number of flights for a given quarter
Automating SkyWrite's information will provide them with the ability to find data in a matter of minutes rather than days.
