Database Reference
In-Depth Information
The Advantage of Learning a Good Design Methodology
You could learn how to design a database properly by trial and error, but it would take you
a very long time and you would probably have to repair many mistakes along the way. The
bestapproachistolearnagooddatabasedesignmethodology,suchastheonein this topic,
and then embark on designing your database.
You'll gain several advantages from learning and using a good design methodology.
•
It gives you the skills you need to design a sound database structure.
A large num-
ber of data processing problems can be attributed to the presence of redundant
data, duplicate data, and invalid data, or the absence of required data. All of these
problems produce erroneous information and make certain queries and reports dif-
ficult to run. You can avoid almost all of these problems by employing a good
design methodology.
•
It provides you with an organized set of techniques that will guide you step-by-step
through the design process.
The organization of the techniques enables you to
make informed decisions on every aspect of your design.
•
It helps you keep your missteps and design reiterations to a minimum.
Of course,
you will naturally make
some
mistakes when you're designing a database, but a
good methodology helps you recognize errors in your design and gives you the
tools to correct them. Additionally, the organization of the techniques within the
methodology keeps you from unnecessarily repeating a given design process.
•
It makes the design process easier and reduces the amount of time you spend
designing the database.
You will inevitably waste valuable time taking an arbitrary
trial-and-error approach to design because it lacks the logic and organization that a
good methodology provides.
•
It will help you understand and use your RDBMS application program more fully
and effectively.
As your knowledge of proper design expands and grows, you'll ac-
tually begin to understand
why
a given RDBMS provides certain tools and
how
you can use them to implement the structure within the RDBMS program.
Regardlessofwhetheryouusethedesignmethodologypresentedinthis topic orsomeoth-
er established methodology, you should choose a design methodology, learn it as well as
you can, and use it faithfully to design your databases.
Objectives of Good Design
There are distinct objectives you must achieve in order to design a good, sound database
structure. You can avoid many of the problems mentioned in the previous section if you
