Day 1
Introducing Visual
InterDev and the World Wide Web
Visual InterDev, the long-awaited Web application development tool from Microsoft,
is finally here. Many developers are applauding its features and the application
development needs that it addresses. Developers now have a tool similar to other
application development tools like Visual Basic and Visual C++ that they can use
to create their Web applications. No more downloading the latest beta copy of a single-focused
tool from the Web. You now have a tool that integrates many of the popular components
and technologies.
During the first day, the context for Visual InterDev will be set, and you'll
be introduce to some of the latest developments concerning the Internet and the WWW.
You will learn about the importance of the Internet. You also will learn about the
rising number of intranets, or private internets, that are growing within many companies.
You will see how the WWW has become ubiquitous and the implications that it has for
individuals and businesses. In discussing the WWW, you will discover the differences
between static and dynamic web pages and what you should focus on for the future.
You will then be introduced to the reasons for having an application development
tool for the Web. Finally, you will get a glimpse of Visual InterDev.
NOTE: In this book, the term Web and WWW are
used synonymously to refer to the commercial collection of Web servers located on
the World Wide Web. The term web is used to refer to pages and sites that are individual
in nature. Most of the time, web refers to pages that you're developing to build
your site.
The Importance of the Internet
You obviously realize the importance of the Internet or you wouldn't be reading
this book. The Internet and the World Wide Web are everywhere. You can't read the
newspaper or watch television without seeing some kind of reference to the Internet.
"Cyberspace" and the "Information Superhighway" have become common
vocabulary for a whole new audience. Virtually every television commercial and print
ad contains a reference like the following:
"For more information, visit us at our Web site at www.whatever.com."
The Internet has come a long way since the old ARPANET days. Originally designed
for research use by the Department of Defense, the Internet has become a haven for
millions of people who have experienced the value of communicating with people around
the world. Internet users have instant access to a plethora of knowledge supported
by this network of networks.
Most people point to 1991 as the beginning of the Internet explosion. In the late
1980s, the academic community began to see the Internet as a valuable tool. Professors
and students at universities around the world began using the Internet as a way to
gain valuable research and knowledge about myriad subjects. Services such as electronic
mail (e-mail), file transfer capability (ftp), and newsgroup discussions all contributed
to the growth of the Internet audience. Then, in 1991, the National Science Foundation
(NSF), which was the major funding group for the Internet, dropped most of its financial
support and allowed commercial traffic onto the Internet. The door was now open for
all types of individuals and businesses to take advantage of this vital communication
network.
We are truly living in the Information Age, and the Internet has become the primary
means for expanding our horizons. The Internet has opened up any number of possibilities
for applications by providing a ready-made network for businesses to use. Growth
in the Internet has also forced us to rethink the way we approach life. A student
in California can communicate with his parents in Florida via e-mail instead of building
up a hefty, long distance telephone bill. In fact, now most families can conduct
conversations over the Internet, thereby skirting the phone companies.
With the growth of the WWW, businesses have been scrambling to gain a presence
on the Internet. In 1995, corporate spending on Internet/intranet systems was $12
billion. This figure is expected to grow to $208 billion by the year 2000. Developers
will play a huge role in helping organizations and businesses understand the importance
of using the Internet from an application and communication standpoint.
The Rise in Intranets
Many companies are realizing the benefits of the Internet from within their companies.
These organizations are creating intranets, which are private, or internal, internets.
These intranets have been established initially as an internal communication tool.
Employees can send e-mail to other employees within the company. Intranets enable
private and sensitive corporate information to be distributed and shared within the
organization. This new medium of communication has become a very cost-effective solution,
especially for geographically dispersed businesses that have employees all over the
world. The time to communicate new policies, procedures, and information is immediately
reduced along with postage and paper costs.
An intranet also can be used for software distribution and for providing access
to vital applications. Companies are now starting to put applications like survey
forms and employee benefit registration forms on their intranets to simplify basic
processes. Businesses also are starting to consider replacing or enhancing their
mission-critical applications (like accounting, sales order entry, oil and gas trading,
and so on) with applications that are secured within an intranet. Intranets are usually
protected and secured by means of a firewall that prevents outside intruders from
accessing the internal network. To the user, there is no difference between accessing
the Internet and the company's intranet. Figure 1.1 depicts a typical configuration
for an intranet.
Figure 1.1.
A high level view of an intranet.
Sun Microsystems is a perfect example of how a company can save real money in
terms of printing, processing, and mailing costs through the use of an intranet.
Sun has used the Internet to communicate basic corporate information, such as organization
charts and geographic office locations. Employees can access monthly updates from
their CEO Scott McNealy which are presented in audio and video formats. Sun also
provides information about its products by providing an online product catalog and
updates on new products. Employee information regarding training, travel, and human
resource policies is placed on the intranet. Sun even provides an "Applications
Chest" that gives employees access to a variety of tools that enhance their
productivity.
Internet performance has become a huge topic of conversation. Some individuals
have even discussed totally redesigning the Internet infrastructure to support the
growing number of users. Without entering this debate, I would like to point out
that intranets provide a way to use the Internet while taking more control over performance
of your applications. With an intranet, a company can use the Internet architecture
model while providing the internal infrastructure to guarantee response time and
security.
Intranet applications also are cost effective from an administration and deployment
standpoint. The browser serves as the universal client for all desktops. The server
makes the desktop come alive by providing information and database access. Deployment
and administration costs are reduced, because you don't have to reinstall an updated
application on everyone's desktops as you do when creating proprietary client-server
applications. Electronic commerce is going to drastically grow in the next few years
and with it will come a continued rise in the use of intranets.
This section has described intranets as being internal to an organization or business.
Private intranets that focus on providing a reliable and secure infrastructure for
groups of businesses also are emerging. Technology companies are beginning to prepare
for this occurrence. Microsoft formed an alliance with British Telecommunications
and MCI to provide private data networks for global companies and their customers.
Private intranets offer the same reliability, security, and guaranteed response
time that a company's internal intranet provides. The difference between them is
that a company's reach extends beyond the internal organization to external entities.
The use of private intranets will continue to rise as application requirements exceed
the current capabilities of the Internet infrastructure.
The Ubiquitous Web
The second explosion that propelled the Internet into national prominence was
the creation of the World Wide Web. The Web has many origins, but most people point
to the time period between 1989-1991 when the Conseil European pour la Recherche
Nucleaire (CERN) European Laboratory for Particle Physics in Geneva, Switzerland,
developed its first specifications. Tim Berners-Lee, a researcher for CERN, developed
the basic concepts of sharing information through the use of a consistent, universal
interface. Mark Andreessen is credited with developing the first browser (Mosaic)
for the Web in 1993. The use of a browser to view the Internet turned attention away
from the information stored on the server, focusing more on the user experience through
the client machine. The browser provided a graphical, point-and-click interface for
viewing Web content that made the Internet easier to access.
The Web is the primary service responsible for bringing the Internet into the
homes of millions. The Web is the most popular and useable service. The hypertext
links to a plethora of information allow the user to experience a "web"
of knowledge. The user can choose the learning path instead of following a sequential
or linear pattern.
The most recent numbers estimate that more than 45 million people have visited
the Web at least once. When sports figures, music celebrities, and news anchors are
touting the Web, you know it has become ubiquitous. The Web provides an alternate
delivery channel for all types of information as well as graphically robust applications.
Major software vendors are totally revamping their products to make them Internet-enabled.
Banks are having to rethink their strategy of targeting and servicing their customers
by providing online banking. Businesses are establishing a presence on the Web to
offer products and services electronically. The Web is everywhere, and we must learn
how to properly and constructively use its capabilities.
The first wave of Web development involved information publishing. Rudimentary
tools were provided to convert documents created with common word processors to the
HTML format of the Web. HTML editors also have provided a way to create original
documents as well as Web pages and deploy them on the Web. As stated, the Internet
and the Web have saved a lot of money for companies in terms of printing, processing,
and mailing costs. The Web has extended the notion of textual documentation to provide
graphical information as well. Graphics, 3D images, audio, and video can truly enhance
the user's experience on the Web. Companies like Macromedia and RealAudio have contributed
to the multimedia experience by providing enhanced and animated graphics and audio
capability. The ESPNET SportsZone is one of the most popular sites on the Web largely
due to the way the site employs multimedia. You can download ESPN commercials both
in audio and video format as well as listen to press conferences and other sporting
events. This site does owe some credit to the popularity of ESPN, but the people
would not be visiting the site if it didn't provide a rich and rewarding experience.
The second wave of Web development has been the creation of functional applications.
These applications extend the simple registration forms commonly seen on Web sites
to become true interactive applications that include database accessibility. These
applications can be classified as just another phase of client-server.
In taking a look at the architecture of the Web, many of the principles have been
carried over from client-server architectures. Figure 1.2 illustrates a typical client-server
architecture.
Figure 1.2.
A typical client-server architecture.
Client-server is a style of computing where the client machine makes a request
of a server machine. The request is usually a request for information, as in a database
request, or for processing, such as updating a database or running a batch process.
The client machine makes the request, and the server machine fulfills this request.
The benefit of client-server systems is that they take advantage of the strengths
of each machine or platform. In a typical scenario, the client handles some application
logic and the presentation to the user while the server provides the back-end processing
and database functions.
In a typical Web application, the browser serves as the universal client that
sends a request for a web page, interprets the HTML document, and displays it to
the user. The web server receives the request through the HyperText Transport Protocol
(HTTP) and returns the required information in HTML format that the client can understand.
Similar to client-server, you can distribute the application processing and database
management portions to varying degrees between the client and the server machine.
Figure 1.3 depicts a typical Web-based architecture.
Figure 1.3.
A typical Web-based architecture.
The main benefit to Web-based applications over client-server is found in the
deployment. In a Web-based scenario, you don't have to deploy a new executable on
each person's desktop with each new application feature or update. The browser serves
as the universal client, providing access to the most current information on the
server. Version control, software distribution, and systems management costs are
significantly reduced for Web-based applications.
A more in-depth discussion concerning how the web client and server interact is
warranted here. Historically, Web applications have been based on HTML and common
gateway interface (CGI) programs on the server. The Web browser interprets the HTML
tags and appropriately formats the page for the user. A web page can be a combination
of formatted text, images and graphics, audio, and video. HTML also allows for the
creation of basic forms that contain text fields, radio buttons, checkboxes, push
buttons, and listboxes. These objects are discussed in more detail on Day 12, "Using
Basic and Advanced HTML Form Controls."
CGI programs have typically been used for processing requests on the server and
distributing information to the client machine. CGI programs, or scripts, are executable
files that can be built using languages such as UNIX shell script, Perl, C, and so
on. As information is updated on your database, the CGI script can handle accessing
the data and passing the information back down to the client browser. The advantage
is that you don't have to write new HTML code for every new document or database
update. The CGI server program provides a reusable component that saves development
time.
I mentioned the HTTP protocol earlier in this chapter. HTTP is the protocol that
allows the browser to connect to a web server. HTTP is a stateless protocol; that
is, the client and server don't maintain a persistent connection. The client makes
a connection to the server and sends a request. The server receives the request,
processes it, then terminates the connection. This process is repeated many times
during a user session. This kind of communication would be like having a telephone
conversation with a friend where you would say something, hang up the telephone,
then dial again to say something else. This dialogue is very tedious. Interactive
applications must have some way to maintain state with the user machine in order
to provide for the needs of applications like sales order processing.
Microsoft and Netscape have led the charge to develop an effective server process
that supports a more interactive state with the client machine. The creation of application
programming interfaces, or APIs, has opened up all kinds of possibilities over the
traditional use of CGI programs. There are several specific benefits to using APIs.
First, APIs are more efficient than CGI programs. A CGI program opens up a process
in memory for each client request. APIs execute processes in the same memory address
space, eliminating the overhead of separate executing processes on one machine. By
using this model, APIs use less memory for executing a process. Also, initialization
with the client machine is performed once for all requests. Another benefit of APIs
is their ability to maintain state. API programs permit a persistent connection between
the client and server, which can be a huge benefit when developing an application
with moderate to intensive database connectivity. Also, separate requests can share
information about the client, because the programs remain resident in memory.
The main disadvantage to APIs is that they're proprietary in nature. Whereas CGI
programs are server-independent, APIs are confined to their respective web server
platforms. Table 1.1 presents the most common APIs and their supported server platforms.
Table 1.1. The most popular APIs, their respective vendors, and supported server
platforms.
API |
Vendor |
Server Platform Supported |
ISAPI |
Microsoft |
Microsoft Internet Information Server, Process Software Purveyor WebServer |
NSAPI |
Netscape |
Netscape Commerce/Communication Server |
WSAPI |
O'Reilly & Associates |
O'Reilly & Associates WebSite |
To summarize, the Web has become popular for a variety of reasons. The Web provides
graphically rich content on a variety of topics to many users. The Web also supports
transaction-based services that enable businesses and consumers to come together
in an electronic market. Examples include ordering books, making airline reservations,
and trading stocks. Learning is also significantly enhanced by having access to all
kinds of documents, white papers, and training materials. Name the subject, and you
can become an expert on it in no time at all by accessing the Web.
The Difference Between Static and
Dynamic Web Pages
Web-based applications have made the transition from solely publishing information
to creating an interactive session with the user. Static web pages represent those
pages that provide information that is nicely formatted in standard HTML. For example,
a person might be able to request an employee benefit handbook to become familiar
with the latest updates in benefits. Static pages are nice, but users want something
more.
Dynamic web pages are those pages that provide true user interaction. In this
model, users interact through the use of server-side programs that provide for an
enhanced experience. Instead of just reading about the latest human resource benefits,
employees can register and update their benefits. Dynamic web pages support the building
of true interactive applications. Once you have read the published flight schedules,
you can make airline reservations electronically over the Internet. Stock brokerage
houses can publish the hottest stock tips and then enable you to capitalize on the
investment through online stock trading. Dynamic web pages provide a world of new
possibilities over static pages.
I briefly discussed the use of CGI and API programs in providing a gateway between
your client and server machine in a Web-based application. Here, I will focus on
the ability to use client- and server-side scripts to create dynamic HTML web pages.
Client-side script is usually associated with objects on the HTML page. These
objects could be standard HTML controls or ActiveX controls. Client-side script is
usually included to make up for the limited functionality of HTML. The script is
included in the HTML page when it is downloaded from the server to the client machine.
The script code executes on the client machine in response to user interaction and
program events. By keeping the script in the HTML page on the server, a developer
only has to make changes to centralized code located on the server. The browser downloads
the revised web page simplifying the software distribution process. The goal in this
model is to keep the code resident on the server leaving little or no code on the
client machine. Some examples for using client-side script include user interface
functions, entry verification, and standard programming functions.
Two of the most popular scripting languages are Netscape's JavaScript and Microsoft's
VBScript. Visual InterDev supports both of these scripting engines, although Microsoft
has implemented its own version of Netscape's JavaScript called JScript. There are
no significant differences between the JScript and JavaScript implementation.
Another way to create a dynamic experience is through the use of ActiveX controls
and Java applets. Visual InterDev includes and supports the use of both ActiveX controls
and Java applets within your application. These controls provide many additional
functions from multimedia to database connectivity. Both JavaScript and VBScript
are used to interact with these controls extending the reach of the interface. Similar
to the use of Visual Basic code with Visual Basic controls, VBScript and JavaScript
serve as the glue between the browser and the particular control. The process is
essentially the same as using a traditional client-server tool like Visual Basic.
You add a control to your page, setting its methods and properties. Once you have
established the basic properties, you add scripting code to handle the application
logic. Visual InterDev incorporates a visual tool for creating client-side script
for your ActiveX controls. The Script Wizard, first included in the ActiveX Control
Pad from Microsoft, provides a visual interface that builds both VBScript and JavaScript.
Visual InterDev also supports the use of Active Server Pages. Active Server Pages
are a new feature included with Internet Information Server 3.0; they provide a framework
for creating dynamic Web pages.
Active Server Pages are based on the ActiveX Scripting engine and enable you to
include server-side executable script directly into an HTML document. You can create
Active Server Pages using any of the popular scripting languages, including VBScript,
JavaScript, Perl, and so on. Figure 1.4 illustrates how an Active Server Page interacts
with a client machine.
Figure 1.4.
This diagram shows how Active Server Pages interact in a Web-based application.
You will notice from the diagram that the web clients communicate with the web
server through the HTTP protocol. The web server can be on the Internet or within
an intranet. The web server is comprised of Internet Information Server 3.0, which
includes the ActiveX Server Scripting engine. The diagram shows the Active Server
pages, or .asp files, where the server-side script resides. These files are simply
HTML pages that contain scripting code. This scripting code extends basic HTML and
provides additional functionality for your application.
Visual InterDev enables you to create Active Server Pages. Some of the visual
tools within Visual InterDev generate much of the server-side script for you. You
have the ability to modify this code as well as create your own server-side script.
You will get your chance to build Active Server Pages on Day 11, "Extending
Your Application Through Active Server Script."
The Need for a New Kind of Tool
There are many extensive and powerful technologies for creating Web applications,
but most tools only focus on a single, specific need. Other tools are being developed
to address a few needs. Developers have been dreaming of the day when they can use
a comprehensive, integrated development environment to build their applications.
Why, you ask, do you need an integrated tool? Take a walk through a typical Web development
effort and look at the many different types of tools that you can use to build a
Web-based application.
First you need an HTML editor. Many people have created a new function for an
old product and made Notepad the HTML editor of choice. Table 1.2 outlines some of
the more robust and popular products on the market.
Table 1.2. Popular HTML editors.
HTML Editor |
Vendor |
Hot Dog Pro |
Sausage Software |
HoTMetaL Pro |
SoftQuad |
NaviPress |
Navisoft |
FrontPage |
Microsoft |
Microsoft also has created add-in products for its Office suite of products that
enable HTML conversion. For example, a user who is familiar with Microsoft Word can
use the Internet Assistant for Word to convert a document to HTML format for display
in a browser.
NOTE: The Office 97 suite of applications
supports the ability to save files for HTML formatting for display on the Web.
Choosing an HTML editor is only the beginning. To build an application, you must
consider the server-side products as well. You have two basic choices, as previously
mentioned: CGI or APIs. If you choose to use CGI, you will need to find a programming
environment based on the language you select. The possible languages include Perl
and UNIX shell scripts, Visual Basic, C, and C++. If you choose an API, you need
to select the appropriate API implementation for your application platform's web
server. Refer to Table 1.1 for a listing of APIs and their supported web server platforms.
API server programs are implemented as dynamic link libraries (DLLs) and built using
either C or C++. Again, you will need to select the appropriate programming environment
to support the selected language.
Java also can be used on the server to provide additional functionality for your
Web-based application. Sun Microsystems built Java as an independent programming
language. It can be implemented as an application program or as a Java applet. A
Java application can interact with system resources and make calls to external programs.
A Java applet is found embedded within a web page and cannot interact with system
resources. Regardless of your Java implementation, an environment will be needed
to support your Java development. Microsoft's Visual J++ and Symantec's Visual Café
are some of the more popular tools for Java development.
You will invariably need to select a scripting language to support the functionality
of your application. Whether it is VBScript or JavaScript, you will need an editor.
Notepad, Visual Basic, and the ActiveX Control Pad from Microsoft all can support
your VBScript needs to varying degrees. Netscape Navigator Gold and Notepad support
JavaScript development.
If you're wondering about connecting your application to a database, many options
exist for database connectivity, depending on how you want to implement your application.
If you're building a Java-based application, you will select a tool that supports
Java Database Connectivity, or JDBC. Most of the popular Java tools also support
JDBC. Microsoft and Netscape also provide environments and tools for database connectivity
based on their API specification.
The point in this example is that you could spend a lot of time and effort using
a number of tools to implement a robust, Web-based application. Compatibility between
the tools becomes a debugging nightmare. Also, you spend a lot of time switching
between the development environments, thereby diminishing your productivity. Due
to these limitations, Microsoft created Visual InterDev to address the many needs
for today's Web-based application developer.
Presenting Visual InterDev
The emphasis in creating Visual InterDev was to provide a tool with a comprehensive,
integrated development environment. Visual InterDev's creators wanted to provide
a tool that enabled developers to utilize many technologies to create and deploy
dynamic, Web-based applications. Microsoft also wanted to emphasize a visual tool.
Many products have been created that enable you to code HTML or connect to a database;
however, these tools typically haven't focused on the ease of use for the developer.
Developer productivity was a major design goal for Microsoft, and they have accomplished
it by providing Visual InterDev with many wizards and visual tools, as well as database
development features. Powerful database integration and connectivity were clearly
of paramount importance for its design. Visual InterDev even supports developers
in deploying their sites once they have been built by integrating comprehensive tools
to create and maintain a web site into Visual InterDev.
Integrated Development Environment
Visual InterDev provides a robust, integrated development environment to address
the many capabilities of the Web. You can integrate various technologies, like ActiveX
controls and Active Server Components, to create a powerful application. The integrated
development environment enables you to use scripting languages like VBScript and
JavaScript to create dynamic applications and Web pages. You can work on simultaneous
projects of different types all from within Visual InterDev's Developer Studio interface.
In addition to Visual InterDev projects, you also can develop Visual C++ and Visual
J++ projects.
Visual InterDev Features
Now that you have been introduced to the features and benefits of the integrated
development environment, it's time for a brief look at some of the specific features
of Visual InterDev. This discussion sets the context for Day 2, in which you will
get to meet Visual InterDev up close and personal.
Visual InterDev includes a wide range of visual tools to augment an application
developer's productivity. HTML editing is significantly enhanced through the use
of the HTML Layout Editor and a version of the FrontPage HTML editor. The HTML Layout
Editor, introduced with the ActiveX Control Pad from Microsoft, enables you to precisely
place your ActiveX controls onto your web page. It also enables you to control the
x and y coordinates to ensure that the ActiveX controls are displayed in the proper
manner. By using this tool, you're able to take more control of your user interface,
and can ensure that the interface you build is an effective one.
Visual InterDev also provides WYSIWYG editing through its own FrontPage 97 HTML
editor. FrontPage enables you to visually author your HTML page. Content authors
can use FrontPage 97 to create files that are completely compatible with Visual InterDev's
version of the FrontPage Editor. Visual InterDev also provides site management tools
that are very similar to those tools provided in FrontPage 97.
The Script Wizard is another visual tool that greatly enhances a developer's productivity.
The Script Wizard enables you to associate specific actions with associated ActiveX
control events. By linking these events and actions, the Script Wizard generates
all of the necessary script language for you. Once the language is generated, you
have the ability to modify and add to the code. This process can save you considerable
development time by generating the routine script and enabling you to focus on the
more advanced code for your application.
Visual InterDev also includes two tools for spicing up your web pages. These tools
focus on multimedia creation and management. The Microsoft Image Composer and Microsoft
Music Producer enable you to create graphical images, music, and sounds for your
web site. You can use the Microsoft Image Composer to create engaging images for
your web pages. The Image Composer supports the Adobe Photoshop file format as well
as GIF and JPG formats. The Image Composer is simple to use, and you don't have to
be a graphic artist to master it. The Music Producer enables you to create music
and sound effects for your web site. You pick from over 100 pre-defined styles of
music and can modify the arrangement of instruments as well as the tempo.
Again, the goal of both of these products is to provide a rich and rewarding experience
for the user. The Media Manager enables you to manage all of your multimedia files
through the use of specialized folders. By using Media Manager, you can properly
organize your images, sounds, video clips, and other multimedia files.
Now consider some of the key features for building robust server applications.
Visual InterDev enables you to create dynamic web pages through the use of Active
Server Pages. The concept of Active Server Pages was touched on earlier in the day.
As a refresher, Active Server Pages are HTML pages that contain server-side script.
The script code can be either VBScript, JavaScript, or some other scripting language.
The Active Server Page, or .asp file, resides on the server machine and executes
before being downloaded to the browser.
Active Server Components are a significant part of building distributed and powerful
applications. Active Server Components are programs, DLLs, or executables (EXEs),
that are built using the Component Object Model (COM) specification. Visual Basic,
Visual C++, and Visual J++ all support the development of COM-based components. These
programs can be called from Active Server Pages to provide robust application processing
on the server machine.
For example, you might want to build an Active Server Component that uses the
strength of the C++ language to perform financial analysis and return the results
to the Web browser. You also can distribute the application processing load through
the use of Distributed COM (DCOM). Active Server Components provide a method for
building high transaction processing capability into your application. Visual InterDev
provides an environment that is conducive to incorporating these components into
your applications.
Database Integration
Visual InterDev provides some very robust database tools. The Visual Data Tools
included with Visual InterDev are easy to use and significantly reduce the time and
effort for adding database capability into your application. Some of the features
include the following:
- Data View. Visual InterDev project window that enables you to view all
of your database objects including tables, views, stored procedures, and triggers.
- Query Designer A tool that enables you to visually build your SQL database
queries and test the results.
- Database Designer A tool that enables you to design, create, and maintain
your SQL database.
- Stored Procedure/Trigger Editor A tool for editing stored procedures and
triggers for Microsoft SQL Server 6.x and Oracle 7.x.
The Query Designer and the Database Designer employ a user interface similar to
Microsoft Access that's very easy to use. You can drag and drop objects into the
workspace and automatically build your SQL queries. You also can use the Database
Designer to populate the database and modify existing data.
Other database features include the following:
- ActiveX Data Objects. An object-based approach to accessing a database
over the Web that uses ActiveX Scripting.
- Database Design Time Controls.Controls geared toward the automatic creation
of database connectivity and generation of Active Server scripting.
- Database Wizards. Wizards that guide you through the creation of an HTML,
data-bound form
Database connectivity and integration is one of the best features of Visual InterDev.
You will get a chance to use these features and tools beginning with Day 8.
Summary
Today you began a glorious journey to the land of Web-based application development.
You started the day with a discussion of why the Internet is important and were introduced
to the significance of learning how to properly use this communication vehicle from
a business perspective. You then moved on to intranets and learned about the rise
in these vital private networks. You learned how businesses use intranets for communication,
software distribution, and applications now and in the future. You then read about
the most popular service of the Internet: the World Wide Web. After reading a brief
history of the Web, you learned about the different waves of Web development.
You also learned about the similarities and differences between Web-based applications
and client-server applications. You found out about the difference between CGI and
API programming. You received an overview of the differences between static and dynamic
Web pages, then learned how client- and server-side script could be used to provide
an interactive experience for the user.
Throughout the lesson, you got a feel for the need for a tool like Visual InterDev.
You were walked through an example that showed the range of tools that could be used
when building a Web-based application. At the end of the day, you were presented
Visual InterDev for your approval. Finally, you got a taste of the features and tools
that are included in the tool. What did you think? I bet that you can't wait until
tomorrow to meet Visual InterDev up close and personal.
Q&A
- Q What's the difference between client- and server-side script?
A Client-side script is included within the HTML page and executes on the client
machine in response to events and user interaction. An example includes validating
data entered into a field before the page is sent to the server. Server-side script
is script that resides on the server machine and is processed on the server before
a page is sent back to the client machine. Server-side script enables you to provide
application processing that can call other application programs, such as an Active
Server Component.
Q Does Visual InterDev support the development of scripts?
A Yes. In fact, Visual InterDev generates much of the scripting for you.
Q What databases does Visual InterDev support?
A Visual InterDev provides connectivity to any ODBC-compliant database including
Microsoft SQL Server, Oracle, Sybase, Microsoft Access, Microsoft FoxPro, and IBM
DB/2.
Workshop
Make sure you have installed Visual InterDev. Tomorrow, you will be taking an
in-depth look at the tool and its development environment. It's important that you
have the tool installed so you can follow along with the exploration of its features.
Quiz
- 1. What is an intranet?
2. What are the two waves or phases of Web development?
3. What are the two most popular scripting languages that help to create dynamic
web pages?
4. Name two of the Visual Data Tools.
Quiz Answers
- 1. An intranet is a private, or internal network, that provides access
to the Internet but is secured from external access through the use of a firewall.
Intranets are used as an internal communication tool and as a medium to distribute
software and provide access to internal applications.
2. The first wave of Web development was the publishing of information. The second
wave of Web development has been application development.
3. VBScript and JavaScript.
4. Possible answers include:
Data View
Query Designer
Database Designer
Stored Procedure Trigger Editor
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