Relational Database Tutorial

http://www.surfermall.com/relational/lesson_1.htm

An introduction to building relational databases.

Concepts of Database Design and Management

http://www.webmasterbase.com/article.php/378

A good tutorial on the theories of designing, developing, and maintaining a quality database.

Your First Database

http://hotwired.lycos.com/webmonkey/backend/databases/tutorials/tutorial3.html

Get ready for a breakneck tour of all the things you need to know to create your relational database. Take a crash course in defining and linking tables. Read the Cliffs Notes to linking your database to your Web server. Have a brief fling with 2-D arrays. Learn just enough SQL, VBScript, ActiveX Data Objects (ADO), and ASP stuff to scrape by. Put the pedal to the metal through HTML forms. And then learn how to put it all together.

Introduction to databases for web developers

http://www.extropia.com/tutorials/sql/toc.html

A very detailed tutorial covering the basics of types of databases and setting up a database, to the more advanced tasks of retrieving and manipulation data.