Function Hierarchy Diagrammer, you can identify the usage of entities and attributes by each function. As an example, Figure 20.19 illustrates a simple function hierarchy for the administrative function at Flugle College.

Figure 20.19.
Function hierarchy
created with Function
Hierarchy
Diagrammer.

Database Design and Application Design Wizards

The Database Design Wizard is a tool that generates SQL statements from an entity relationship diagram, thereby implementing the physical database from the logical model that Designer/2000 maintains in its repository. Similarly, the Application Design Wizard will generate a module or menu from a function, implemented in one of the Developer/2000 components—such as Forms or Reports.

Module Structure Diagrammer

The Module Structure Diagrammer is used to create and modify modules and their details. This tool also enables you to describe how modules are related to one another. A module may be one of the following:

• Screen
• Report
• Menu
• PL/SQL subprogram (package, procedure, or function)
• Chart

For example, Figure 20.20 displays a tabbed folder for specifying the Flugle College Course Catalog, which is a report.

Figure 20.20.
Specifying the module
details for a report in
the Module Structure
Diagrammer.

Summary

In this final lesson, the key concepts to remember are the following:

• Database Designer is a database diagramming tool that can help you develop a database design and build it for a variety of databases—for example, Oracle, RDB, DB2, and SQL Server.
• With Database Designer, you graphically describe your database design: tables, columns, constraints, and indexes.
• Database Designer can generate a physical database from the design that you specify.
• Database Designer enables you to document each table and column, thereby capturing a complete database design in one source.
• Database Designer saves a database design in a file with an extension of .ODD.

Q&A

Q Can Database Designer and Designer/2000 exchange information?
A Yes. Of course, Database Designer uses a small subset of the information that Designer/2000 maintains in its repository. As an example, Database Designer lets you specify the display characteristics of a column. It can pass this information to Designer/2000, which will use it in the generation of screens and reports.

Q If I'm developing a small application, do I even need to use a tool like Database Designer or ERwin?
A It really is a good idea to use an ER diagramming tool like Database Designer or ERwin. As you may already know, small projects are typically subject to "scope creep"; that is, the scope of the project is enlarged by many of the participants. Database Designer or ERwin will help you manage a growing number of entities, attributes, and relationships.

Workshop

The purpose of the Workshop is to allow you to test your knowledge of the material discussed in the lesson. See if you can correctly answer the questions in the quiz before you continue with tomorrow's lesson.

Quiz

1. True or false? One drawback to Database Designer is that it supports only Oracle databases.
2. Name three advantages of using Database Designer instead of a text editor to create the DDL statements that implement a database design.