Programming PHP

Sample Application

Because web database applications are such a mainstay of web development, we’ve decided to show you a complete sample application in this chapter. This section develops a self-maintaining business listing service. Companies add their own records to the database and pick the category or categories by which they want to be indexed.

Two HTML forms are needed to populate the database tables. One form provides the site administrator with the means to add category IDs, titles, and descriptions. The second form, used by the self-registering businesses, collects the business contact information and permits the registrant to associate the listing with one or more categories. A separate page displays the listings by category on the web page.

Database Tables

There are three tables: businesses to collect the address data for each business, categories to name and describe each category, and an associative table called biz_categories to relate entries in the other two tables to each other. These tables and their relationships are shown in Figure 8-3.

Figure 8-3. Database design for business listing service

Example 8-2 contains a dump of the table schema in MySQL format. Depending on your database’s features, the schema may have to be altered slightly.

Example 8-2. Database schema

# -------------------------------------------------------- # # Table structure for table 'biz_categories' ...