A database is a collection of information, or data, arranged in a particular manner. The basic unit of information in a database is called a record. Each record in a database contains two or more fields that hold specific types of information. Perhaps the most common example of a database is an address list. Each entry in the database constitutes one record: an individual’s name and address information. Each record in the database contains fields that hold separate items of information: first name, last name, address, city, and so on. These fields are the same for every record in the database, and they are assigned names identifying the data they contain.
A database is sometimes displayed in row and column format. Each row contains one record, and each column contains one field, as illustrated in Figure 19.1. In this case, a single record can be referred to as a row, and an individual field as a column. The entire collection of records is called a table. Some databases contain more than one table, with the records in each table having a different field structure. We will deal with multiple-table databases in later chapters; for now, we’ll stick to single-table databases.
A database program is designed to let you work with the information in a database. Some capabilities are common to any database program—adding, finding, and deleting records, for example. Many other capabilities are customized to fit a specific program. In an address list database, for example, you may want the ability to print envelopes and sort the records by ZIP code. A graphics database might need the ability to input and store images from a scanner. The possibilities are endless. If you write database programs as part of your job, you never know what someone might ask you to do next. Here’s one of the advantages of Visual Basic: As a full-featured programming language, it offers the flexibility to build many capabilities right into the database program. Thanks to its database tools, most of the fundamental database tasks are simple to accomplish.
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