Database Reference
In-Depth Information
dundant data, you must be sure to make the same modification for each instance of
that value.
•
Impaired data integrity:
Bending or breaking the rules often violates one or more
components of overall data integrity, such as table-level integrity and relationship-
level integrity. It will be your responsibility (or that of your application program)
to compensate for the lack of integrity—in whatever way it manifests itself—as
best as you can.
•
Inaccurate information:
You cannot possibly expect the database to provide
accur-
ate
information if it has any of the aforementioned problems.
Improving Performance by Other Means First
If you still think you want to pursue this course of action in order to improve processing
performance,
do it only as a last resort.
Before you take these measures, however, try to
improve performance by some other means first. Consider these alternatives.
•
Enhance or upgrade the computer hardware.
Cost is not quite the issue it used to
be, so this is still the easiest way to increase processing performance. Items such as
a faster CPU, more memory, faster and more efficient disk drives, and a printer
that better meets your printing requirements will all help to greatly decrease the
time it takes the RDBMS to process a complex query or report.
•
Fine-tune the operating system software.
Make certain that the computer's operat-
ing system is optimized for peak performance. This is especially important for net-
worked computers and server hardware. You can greatly enhance general process-
ing performance by working with the configuration options settings. The types of
modifications you make to the operating system in general will depend on your op-
erating system, so you'll have to refer to your documentation to determine what
types of modifications you can make.
•
Review the database structure.
Make absolutely certain that the database is prop-
erly designed. It makes quite a difference. Poorly designed databases actually
con-
tribute
to poor processing performance.
•
Review the database's implementation.
Examine how the database is currently im-
plemented within the RDBMS. Make certain you've taken full advantage of the
RDBMS's capabilities and defined the database as efficiently and completely as
possible.
•
Review the application program used to work with the database.
Here's another
area you should examine very closely. Is the application program well written?
Does it make the best use of the tools the RDBMS provides? Are the application's
components well defined? In some cases, a report may print more slowly because
