Understanding Database Concepts

Simple database programs, such as the Database component of Microsoft Works, can store information in only one table. These simple databases are often called flat file databases, or just flat databases. More complex database programs, such as Access, can store information in multiple related tables, thereby creating what are referred to as relational databases. If the information in a relational database is organized correctly, you can treat these multiple tables as a single storage area and pull information electronically from different tables in whatever order meets your needs.

A table is just one of the types of objects that you can work with in Access. Other object types include queries, forms, reports, pages, macros, and modules.

Of all these object types, only onethe tableis used to store information. The rest are used to manage, manipulate, analyze, retrieve, display, or publish information stored in a tablein other words, to make the information as accessible and therefore as useful as possible.

Tip

Access 2007 introduces a new file storage format that uses the .accdb extension. You can open old Access databases (with an .mdb extension) in Access 2007 and save them in the new format, but after they're converted, you will not be able to open them with a previous version of Access.

The new format supports many new features. For more information about this format, search Access Help for accdb.

Over the years, Microsoft has put a lot of effort into making Access not only one of the most powerful consumer database programs available, but also one of the easiest to learn and use. Because Access is part of the Microsoft Office system, you can use many of the techniques you know from using other Office programs, such as Microsoft Office Word and Microsoft Office Excel, when using Access. For example, you can use familiar commands, buttons, and keyboard shortcuts to open and edit the information in Access tables. And because Access is integrated with other members of the suite, you can easily share information between Access and Word, Excel, or other programs.

In its most basic form, a database is the electronic equivalent of an organized list of information. Typically, this information has a common subject or purpose, such as the list of employees shown here:

ID	Last name	First name	Title	Hire date
1	Anderson	Nancy	Sales Rep	May 1, 2003
2	Carpenter	Chase	Sales Manager	Aug 14, 2001
3	Emanuel	Michael	Sales Rep	Apr 1, 1999
4	Furse	Karen	Buyer	May 3, 2004

This list is arranged in a table of columns and rows. Each column represents a fielda specific type of information about an employee: last name, first name, hire date, and so on. Each row represents a recordall the information about a specific employee.

If a database did nothing more than store information in a table, it would be no more useful than a paper list. But because the database stores information in an electronic format, you can manipulate the information in powerful ways to extend its utility.

For example, if you want to locate a person or a business in your city, you can do so because the information in the telephone book is organized in an understandable manner. If you want to get in touch with someone a little further away, you can go to the public library and use its collection of phone books, which probably includes one for each major city in the country. However, if you want to find the phone numbers of all the people in the country with your last name, or if you want to find the phone number of your grandmother's neighbor, these phone books won't do you much good because they aren't organized in a way that makes that information easy to find.

When the information published in a phone book is stored in a database, it takes up far less space, it costs less to reproduce and distribute, and, if the database is designed correctly, the information can be retrieved in many ways. The real power of a database isn't in its ability to store information; it is in your ability to quickly retrieve exactly the information you want from the database.

Because you can use standard Web programming code to easily manipulate the information in an Access 2007 database, you can create Web sites based on the information in your database or share that information with visitors to your site.