CHAPTER 14

Using Databases

The emergence of Web-friendly interactive databases has been fueled by eCommerce. Education is also benefiting from the development of friendlier tools to create interactive Web page components. It is now possible to choose from several strategies to incorporate interactive components into your online course. The potential applications for such software in teaching are enormous.

A database is a collection of data organized so that its contents can be readily accessed, managed, and updated. Using database applications in conjunction with Web pages allows the text, graphics, and feedback displayed on a page to be rendered dynamically at the time the page is requested. This allows the instructor to customize pages, and to provide feedback and information relative to conditions or matching fields for each individual user. Most of the courseware packages have database functions built into them. However, if you are interested in adding customized interactive components and Web pages for your students, selecting a database application to use with your Web site will add a wide range of interactive options to your course design.

Using databases at your Web site adds functionality at two different levels. You can use the power of the features in the database application itself. You also can use some advanced HTML and/or Javascript coding to create interactive components.

Most designs for using databases are based on an interactive exchange of information between the user and the server. HTML code can request that information from a database field or record be displayed on a Web page. At commercial Web sites, the user requests specific information to be displayed. The user can send a query or submit information to the site, or search a site and only view the relevant information.

Similar functions can be applied to online course design. There are some real advantages to adding a component that allows the server to get information from a user and return specific information as a result of the interaction. Some examples of how a database application might be used in Web-based environments would include:

• discussion forums
• data entry
• selected display on dynamically rendered pages
• search and display functions to select information to view
• quiz/test functions
• feedback display
• shared student work spaces for projects

The combination of a database and HTML really allow the instructor to create specific or unique interactive features for their Web site. The two main reasons to use a database application with your Web pages are to customize information displayed on pages, and to collect data by allowing users to submit information using HTML forms.

There are several advantages to using a database to render Web pages dynamically rather than to create 'static' Web pages. Rendering a Web page reduces the number of pages that must be created and stored. Imagine the time-intensive labor involved if every item for sale at Amazon.com required its own HTML file stored on a server.

Web pages generated from database information are easily customized. An instructor can customize course information or feedback about an assignment or a student's progress. The information displayed on the page can be based on a user login and password that matches fields in a database. When the user is identified, specific fields from the database can be displayed to show which assignments have been completed, and the grade for each complete assignment.

Partially completed assignments and works in progress can be displayed, and the changes saved as several students contribute to the same project. The instructor can design the access to the project such that the contributions of individual students are tracked. Whiteboard and video conferencing software contain features that allow for synchronous use on a shared file by more than one user.

Dynamic Web pages can support a two-way exchange of information. Sometimes that information can be used solely for determining a response. However, there are more options when designing the interaction. The instructor can maintain complete control over the list to ensure the materials are all appropriate or make the list interactive, allowing students to contribute links they have discovered.

If an instructor wants students to contribute URLs for a class resource page, students can e-mail URLs to the instructor and the instructor can manually edit the lists and add them to the Web site. But it is more efficient to automate the process of submitting and posting the URLs. By creating a form for submitting the URLs directly to the database, the instructor will reduce the workload to updating and maintaining the Web page to display the URLs from the database. The instructor can choose to add a search function to allow users to view only the URLs contributed after a specific date or in a specific content area.

Most database files can hold all types of information: text, numeric values, and graphics. Number or value fields might be calculated fields that provide individualized user feedback. Images might be stored to create an instructional resource, or to display an image of each student on a course participant page. A field might be used to record what has been displayed randomly to a learner.

The possibilities for designing interactive components with a large variety of features are extensive.

Many database applications are available. FileMaker Pro and Microsoft Access are common choices. We have used HyperCard (Macintosh only) in an extremely wide array of applications. SuperCard (Macintosh only) and ToolBook (Windows only) enjoy extensive use as database applications. Each program has different features and limitations.

The server must be able to communicate the input information to the database. There must be some structure to handle this interaction. Prior to selecting a database application, consult the server administrator to find out if there are any limitations about which applications or formats will run on the server. There are several options depending on the operating system and Web server software being used on the machine. Many times Common Gateway Interface (CGI) scripts handle the incoming information submitted by the user, and the resulting feedback from the database file.

The "Web Companion" feature in FileMaker Pro eliminates the need for CGI scripts and performs this task. The Web Companion feature must be enabled; when enabled, it sets up its own server software. All of the database files and HTML files that need to communicate are housed in a web folder in the FileMaker Pro application folder. Along with the "Web friendly" features provided, most applications also have increased security features. Assigning logins and passwords to control access to the database file is a good idea, especially if it contains any type of sensitive information such as grades or ID numbers.

FileMaker has an associated language, CDML (Claris Dynamic Markup Language). This language may be used to link the information from forms on Web pages to FileMaker databases. HomePage, a Web page creation program, facilitates the creation of pages with forms that use CDML to link to FileMaker databases.

The databases we have mentioned are quite powerful. In some situations, however, application programs capable of handling very large databases are required in order to provide either the size or speed needed to support a process. Most of us in education never face this level of demand. In a few situations, however, this demand is possible. There are competing standards and products. SQL (Structured Query Language) is a standard (ANSI, ISO) interactive and programming language for getting information from and updating a database. Professional programming assistance is usually necessary to work with a major database software package.

Cookies are small text files that are written on the client's hardware that become available to browsers. The user of the browser software must give permission before a cookie can be written. Permission can always be granted, always denied, or obtained on a case-by-case basis. As often as not, eCommerce sites use cookies to manage their relationships with customers. After the first time you do business with an eCommerce site, they seem to know a great deal about you. When you first log on, the business writes a cookie to your hard drive. Thereafter, when you log on, it uses this cookie to get enough information to search you out in its own database and decide what offers to recommend to you. The important data is at the eCommerce site; the cookie is what gives them the opportunity to know what to offer you. These schemes are heavily protected; before any key information is displayed, the user of the browser software will need to offer some verifying information. Cookies often are described as invasive or dangerous. In fact, they are useful tools. In a well-managed educational site, for example, a cookie is a means for starting a reentering student at the same place she left a structured instructional sequence.

There are numerous database resources in the public domain. It is reasonable to ask students to use readily accessible data to gather information. It is better to have the students put the information to use. When reading scores were published on a school-by-school basis in Lincoln, Nebraska, an instructor at UNL had students create a 3-D map of the city. For each school, reading scores and average family incomes were plotted, showing a remarkable positive correlation.

A very practical example that combines text and graphic information is the generation of maps of specific locations. Figure 14.06 shows a map generated from a database.

The Web is a place where scientific data abounds. For example, data are available for the best estimates of the atomic masses of all known nuclides (atoms), as in Figure 14.07.

A principal theme of this book is that decisions about instruction should be based upon research where possible. The Web will be used in teaching because it is fast becoming the internationally predominant medium for communication. The Web is a marvelous system for delivering multimedia instruction. However, as we noted early and repeatedly, the use of multimedia in instruction, by itself, does not often lead to improved learning.

The remarkable thing about the Web, however, is that it affords the opportunity to study learners in a fashion heretofore not possible. Crippen et al. [2000] report details of student use of a Web site designed to help them prepare for a specific item on the Advanced Placement Chemistry Test. This is an example of using Web databases to gather information about learning. This particular site gathers information about both access and performance. As indicated in Chapter 9, distributed practice leads to improved learning performance as compared to concentrated practice. A major finding in the study of the AP Chemistry site is that students hit the site most frequently during the week before the AP Chemistry Test, with the day before the test being the peak day. Unpublished observations by Orr [2000] suggest that student procrastination until the last moment before a course deadline can be so serious as to create problems due to heavy server traffic.

Servers can maintain logs that capture varying degrees of information. Figure 14.08 shows a modified screen capture of a server log. The log file is a text file. It is possible to import files of server logs directly into database software for analysis. If you go to the trouble of setting up a learning Web site, especially one with new materials, then using the information from that site to study student learning seems prudent.