Database Reference
In-Depth Information
This chapter covers a majority of the terms that define the ideas and concepts of the design
process, including definitions and somewhat detailed discussions for each term. (I provide
pertinentdetailsornecessaryfurtherdiscussionforagiventermatthepointwheretheterm
isexpressly usedwithin aspecific technique inthe design process.) There are several other
terms that I introduce and discuss later in the topic because I think you'll more easily un-
derstand them within the context of the specific idea or concept to which they relate.
Note
The glossary contains concise definitions for all of the terms in this chapter and
throughout the topic.
There are four categories of terms defined in this chapter: value-related, structure-related,
relationship-related, and integrity-related.
Value-Related Terms
Data
The values you store in the database are
data.
Data is static in the sense that it remains in
the same state until you modify it by some manual or automated process.
Figure 3.1
shows
some sample data.
Figure 3.1. An example of basic data
This data is meaningless at this point. For example, there is no easy way for you to de-
termine what “92883” represents. Is it a zip code? Is it a part number? Even if you know it
represents a customer identification number, is it one that is associated with George Edle-
man? There's just no way of knowing until you process the data.
Information
Information
is data that you process in a manner that makes it meaningful and useful to
you when you work with it or view it. It is dynamic in the sense that it constantly changes
relative to the data stored in the database, and also in the sense that you can process it and
presentitinanunlimitednumberofways.YoucanshowinformationastheresultofaSQL
SELECT
statement, display it in a form on your computer screen, or print it as a report. The
point to remember is that
you must process your data in some manner so that you can turn
it into meaningful information.
