What are Web Databases?
The Internet and its user-friendly application, the Web, would be practically useless if users could not access databases online. The premise of the Web is that people can not only browse visually appealing Web pages, but also search for and find information in databases. When a shopper accesses an online store, he or she can look for information about any of thousands or hundreds of thousands of items offered for sale.
For example, when you access the site of CDNOW (nowadays part of the amazon.com group of companies), you can receive online information (such as an image of a CD's cover, its popularity ranking, price, and shipping time) for any of a half million music CDs. If you access IBM's site, you can retrieve information on each of thousands of products and services or select an article from a huge electronic library. In business-to-business e-commerce, wholesalers make their catalogs and special prices available to retailers online.
Behind each of these sites is a database. The only way for organizations to conduct these types of Web-based businesses is to give people outside the organizations access to their databases. In other words, the organizations must link their databases to the Internet.
Web databases are used in many ways, such as:
1. Catalogs - in both business-to-business and business-to-consumer e-commerce. Catalog databases allow browsers to search items by keywords or combinations of keywords. Many sites provide a local search engine that scours only pages of that particular site.
2. Libraries of books, articles, CDs, and movie clips. These types of sites also often include a local search engine that allows a user to search for the keywords in a title, author name, or in an entire article. University faculty, staff, and students often have access to such large databases through their schools. Most of these databases are not owned by the school, but are operated by organizations that specialize in running library databases such as ABI/Inform and UMI.
3. Directories, which can include names, addresses, telephone numbers, and e-mail addresses. For instance, professional associations can provide members with access to membership lists.
4. Client lists and profiles. Usually, individual users have access to these databases only for the purpose of inserting or updating their own records. A registered usemame and password are usually required to gain access to these databases. For example, Valupage, a Web site that provides supermarket coupons online, collects data on shoppers. To receive periodic e-mail messages with coupons that you can print out and use for supermarket discounts, you must first enter personal data, including your address, e-mail address, and shopping preferences. The data are sold for profit to other organizations.
From a technical point of view, online databases that are used via Web browsers are not different from other databases; however, an interface must be designed to work with the web. The user must be provided with a form in which to enter queries or keywords to obtain information from the site’s database. The interface designers must provide a mechanism to parse data that users insert in the online forms, so that the data can be placed in the proper fields in the database.