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Oracle Database 10g includes a complete development and deployment environment for developing
applications without the use of any other programming tool. This environment is called HTML-DB,
since both the developer and user interface to its applications is a basic browser.
The first section gives you a basic introduction to the use of this tool. Since HTML-DB is highly
wizard-driven, you can probably learn it best by creating a simple application, which you will do
in this chapter.
What Is HTML-DB?
Architecturally, HTML-DB is a collection of PL/SQL packages that make up the application. The
packages that are the core of HTML-DB provide a declarative HTML development environment
that prompts you for information about the specifics of your target application. Once you have
supplied this information, the PL/SQL packages in HTML-DB generate another set of PL/SQL
packages that can make up the application.
This simplified explanation of the architecture and implementation of HTML-DB skips over a
great deal of the functionality offered by the tool. HTML-DB includes the ability to automatically
create menus and navigational aids to pull together different parts of an application, as well as a
complete HTML-based interface to SQL and database object maintenance for an Oracle database.
In addition, you can use HTML-DB to quick-start application development by easily importing
data from other sources, such as an Excel spreadsheet. You will learn more about these capabilities
as you explore HTML-DB by creating an application in the course of this chapter.
If you are familiar with Oracle technology over the past several years, this description may sound
a bit familiar. Didn’t Oracle have another product that sounded quite a bit like HTML-DB?Well, yes. The product originally known as WebDB was introduced with Oracle8i as part of the database.
This tool used PL/SQL packages to create HTML-based applications. The development tool, like the
deployment environment, was browser-based. WebDB became Oracle Portal, with an emphasis on creating
a common interface to different applications, through portlets, as well as a way to collect information
from different sources. Oracle Portal is now a part of Oracle Application Server.
Some of the key members of the original team that created WebDB are also part of the team that created
HTML-DB. If you detect some similarities, it’s probably more than a coincidence. But the emphasis in
Oracle Portal has moved away from the creation of applications to the creation of unified access to a
variety of different applications and data sources. Portal still has application development capabilities,
but HTML-DB is aimed directly at the need to create HTML-based applications that access Oracle data.
The biggest difference between HTML-DB and Oracle Portal is in the packaging—HTML-DB comes as
a part of Oracle Database 10g and Portal comes with various bundles of Oracle Application Server.
The HTML-DB Environment
Before moving on to installing and using HTML-DB, you can look at the broad areas of functionality
provided by the product by taking a brief tour of the overall HTML-DB environment.
The development interface to HTML-DB is steadily evolving, so, depending on when you read this
chapter, the interface you see might be slightly different from the one shown in this chapter. The basic
usage of the interface, however, is still essentially the same.
Figure 23-1 shows the home page for an HTML-DB developer.
You can see the three broad areas of HTML-DB functionality on this page:
? Application development, which gives you the ability to create modules and assemble them
into flows, or applications
? SQLWorkshop, which acts as a browser-based interface to using all kinds of SQL against
database objects, including SQL to create or modify database objects or system parameters
? Data Workshop, which helps you to load data to your Oracle database and unload data from
your Oracle database in a number of common formats
You will be using some of the capabilities in two of these areas in this chapter when you build a simple
sample application.
Please be aware that the remainder of this chapter takes you on a quick flyover of HTML-DB. This exercise
will give you some idea of the way that HTML-DB works and how you can use some of its capabilities,
so you can decide if this solution might be right for you. But entire books can be written on this
topic—I know, I wrote a couple on its predecessors—so the depth and breadth of the product cannot
be covered completely in a single chapter.SapereOnLine |
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