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Tutorial:
Database - The Need For Web Applications
Dr.
Thomas E. Hicks
Computer Science
Department
Trinity University
The Internet is rapidly becoming more interwoven into our daily commerce, marketing, research, shopping, business, education, and recreation. Cyber Demographics reports that 58% of Americans regularly use the Internet; according to research from the Pew Internet & American Life Project, only about 24 percent of Americans experience life unplugged [1] "Nearly 80 percent of college students in the US say the Net has had a positive impact on their college academic experience; 72 percent of students check their email everyday. [2]
Most of the user counts are computed from databases distributed by Internet Service Providers (ISP). Colleges and universities often function as an ISP for their campus. Since most colleges and universities refuse to share their user database, they often count as one user in the statistics; in reality, there are often thousands of confidential users behind the educational domain names.
Some companies are also large enough to be their own ISP and also choose to keep their databases confidential; these too statistically count as one user. The majority of companies connect to the internet through one or more pieces of hardware that function as a firewall-router. This router is assigned one IP address; behind the router may be tens, hundreds, or even thousands of users. These companies also generally count as one in the user statistics.
Until this trend changes, the statistics reflecting user counts will continue to be both low and approximate.
CommerceNet also tells us that the number of new users has increased 16% in the last 9 months and that users involved in web purchasing have increased 40% in the last 9 months. [1] Since the numbers related to colleges, universities, and large businesses that serve as their own ISP are relatively constant, these growth statistics are staggering.
The amount of information available on the Internet is expanding rapidly; one of the speakers on Tech Web said that the amount of information is growing at a rate of more than 15% per month. More than one hundred search engines enable users to search huge databases for desirable information. In addition to web page information, Internet databases are being used to store information about hundreds/thousands of topics; included would be personal information, corporate information, geological and map-type information, organization information, statistical information, etc. Keeping information current is one of many practical problems facing almost all databases.
Databases can be maintained in a number of ways; maintenance includes adding new records, deleting old records, editing/changing existing records, and querying/searching the database for some type of conditional match.
Some of these databases are maintained manually; a collection of data entry personnel type in information that has been collected from Internet Mail and Internet forms. The problems associated with this approach is that it is expensive, never quite up to date, and potentially entered erronously.
It is often important to place information directly into the database. There are three interface options to placing information directly into the database.
A SQL Command Interface can be used to enter traditional SQL commands in a text window. Whereas this is appropriate for the database programmer, it is not at all appropriate for the general public.
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A Dedicated Application written can be used enter data. This application may be written using Java, Visual Studio Net, Visual Basic, or any of a number of other programming languages. These applications generally require installation on the host. These applications are often operating system specific. These applications sometimes require the purchase of support software or interfaces.
These dedicated applications enable concurrent users to alter centralized databases stored on a local area network; users can add new records, delete old records, edit/change existing records, and query the database. These applications are often tremendously expensive and time consuming to write/test/and maintain. A few long distance users, using a communication package such as PC Anywhere, may be able to access the database by taking over an existing workstation thus emulating a local user; this tends to be slow and ties up workstations. Successful usage, for the most part, is limited to the outreach of the local area network. Good Graphical User Interfaces (GUI) are essential.
Applications written in a database programming language, such as FoxPro, Access, Paradox, provide another alternative. These too enable more than one user to alter information that resides on a local area network. Some of the environments that fall into this category require a shell and others compile into a stand-alone application. Great GUI-based applications can be easily constructed; these will enable the Users to add new records, delete old records, edit/change existing records, and querying the database. It is possible for a few long distance users to use a communication package, such as PC Anywhere, to take over an existing workstation and pretend to be a local user; this tends to be slow via the modem and ties up workstations. Successful usage, for the most part, is limited to the local area network. Good Graphical User Interfaces (GUI) are essential. These applications are generally much less expensive to write/test/and maintain than the stand-alone applications; they are certainly easier to modify. Microsoft FoxPro is an example of a database programming environment which can compile a stand-alone application; the install disks include the .dll's necessary to run the application; there are no fees paid to Microsoft for each application used. Microsoft Access is an example of a database programming environment which requires that at least a minimal shell be installed on each workstation that is to use the database application; paying for the additional legal copies of Access increases the costs.
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A Internet Web Server & Interface Application written can be used enter data. This application uses a middleware language such as Pearl, C++, C#, ASP, PHP, or JSP to interface a browser to the database. It requires nothing special on the host except a browser.
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The Internet Web Server applications require web server software, such as IIS or Apache, Personal Web Server, to be installed on the server. IIS is freely distributed with most of the Microsoft applications. Apache is also free for Linux and Windows users.
IIS 5 Installation on Windows 2000 Pro/Server
IIS 5 Install on Windows XP Pro
[1] http://cyberatlas.internet.com/big_picture/demographics/article/0,,5901_2192251,00.html, June 1, 2003.
[2] http://www.nua.ie/surveys/index.cgi?f=VS&art_id=905358385&rel=true, June 1, 2003.