HP Integrity NonStop J-Series - Manual (Page 231)

Sample Project-Tracking System
Identifying Classes of Data
DEFINING THE DATA REQUIREMENTS OF THE SYSTEM
The next step in developing an application system is to identify
the information needed to carry out each function. To define
these data:
1. Identify classes of data that interest the users of the
application system. These classes of data will correspond to
files accessed by the application system.
2. Identify the data items that belong to each class of data.
These data items will correspond to the fields within the
files.
3. Determine the relationships that exist between classes.
Identifying these relationships will help you later when you
build the tree structures for the applications.
4. List the fields in each file. This step and the following
step will help you when you create record descriptions for
the files.
5. Identify key fields for each file.
6. Normalize the files. Normalized files are simple to
maintain, easy to link within applications, and easy to
obtain reports from when using ENFORM.
7. Use the Data Definition Language (DDL) to create the record
descriptions and data dictionary that describe the files.
Identifying Classes of Data
For the project-tracking system, you can determine two classes of
data that are of interest to users: the projects that
application tracks, and the events associated with each project.
You can identify these classes more precisely by examining the
way that projects are currently tracked within the department,
and through discussion with its employees, you might discover the
following procedure:
1. A project manager fills out a form that describes the
project, listing a project code (a unique number that
identifies each project), a brief description of the project
and its estimated starting and ending dates. The project
manager then files this form for later use.
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