Managing Information Technology

Chapter 8 • Basic Systems Concepts and Tools 333

(A) Sales Summary System

(B) Produce Sales Summary Subsystem

Sales

Summaries

Valid

Customer

Orders

Rejected

Orders

Customer

Orders

Product

List

Sales

History

Valid Customer

Orders Monthly Dollar

Sales Summary

Product Sales

Comparison

Sales

History

Produce

Sales

Summaries

Sorted

orders

by month

Sorted

orders

by month

Sorted

orders

by month &

product

Verify

Customer

Orders

Sort orders

within month

by product

Calculate

total dollar

sales by month

Calculate

total dollar

sales by

product and

compare to

history

Sort orders

by

month

FIGURE 8.4 Sales Summary Reporting System and Subsystem

FilteringDisposing of useless data (or noise)

Coding/decodingTranslating data from one format
into another (e.g., switching between two-part
numbering schemes, one used by marketing and
another used by engineering)

Error detection and correction Checking for

compliance to standards and for consistency;

by isolating this task in interfaces, other compo-

nents can concentrate on their more essential

responsibilities