OVERVIEW OF MAJOR COMPONENTS - Database Design and Development: An Essential Guide for IT Professionals - page 62

Billing Information

Available Fields
Customer Name
Invoice No.
Invoice Date
Billed Amount
Paid Date
Paid Amount

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buttons

Billing
data

DATABASE
ENGINE

REPORT WRITER

DATA
REPOSITORY

QUERY PROCESSOR

Security Module

Structure of
billing data
Security Authori-
zations

I/O Module

Billing Report

DBMS

Customer
Name
ABC Company
Roger Smith
Shaina Benson

Invoice
Number

Invoice
Date

Billed
Amount
1,050.00
975.00
750.00

Paid
Date

Paid
Amount
1,050.00
500.00
750.0

DATA
DICTIONARY

1124
3256
7354

12/5/2002
1/6/2003
2/1/2003

12/31/2002
1/15/2003
2/25/2003

Figure 2-12 Report writer: design and execution.

• Incorporation of report break levels and subtotals
• Usage of subqueries during execution of reports
• Customizing reports with boilerplate graphics and text
• Generation of specialized formats: mailing label, form letter, matrix
• Dynamic reports using dynamic query parameters

Applications Developer

We have discussed the components of query processor, forms generator, and report
writer. The outputs of these components form the basis for developing applications
for the users. An application consists of forms, reports, and underlying queries. The
set of forms and reports provides the users with the capabilities to input, retrieve,
and manipulate data in the database. In a sense, an application is a complete
package to serve the needs of the users for performing their specific day-to-day
tasks. Sales entry, order processing, inventory control, payroll, employee project
assignment, and general ledger are examples of applications built with forms,
reports, and queries.
The applications developer or applications generator component assembles the
outputs of other components to develop coherent systems to support specific func-
tions in the organization. The applications developer components enable the use of
menus, submenus, and navigation among various execution options. Small applica-
tions consist of just a handful of forms and reports. With the powerful applications
developer in modern DBMSs, you can put together a small application easily and