Introduction

Linux is a computer operating system that is designed to work like the UNIX operating system, which for 25 years has been the operating system of choice for serious work with networks and databases. Linux transforms your personal computer from a glorified typewriter-cum-game-machine into a powerful workstation with which you can control networks, run multiple programs simultaneously, send and distribute Internet mail and news, and manage complex databases.

Linux is offered to the public under the Free Software Foundation’s copyleft, which means that it and its source code is available free of charge, subject to a few carefully articulated restrictions. Linux makes the power of UNIX available on an average personal computer And Linux is free—the gift of a talented and generous community of programmers around the planet.

One of most important tasks that Linux makes possible is the management of complex databases. The power of Linux lets you create relational databases, program them, and let users work with their contents over the Internet.

In today’s information-intensive world, the management of data is becoming ever more important to groups that used to get by with paper-based record-keeping:

•  Small businesses, to track inventory, income, and costs.

•  Not-for-profit groups, volunteer groups, and churches, to manage work, expenses, and income.

•  Researchers and scientists, to help manage their detailed records of results.

•  Elementary schools and high schools, to track students’ progress, communicate with parents, manage inventory and donations—and even teach some computer science.

•  Larger companies that want to explore open systems, relational databases, and the Internet, but do not want to spend an enormous amount of money on hardware and software.

These peoples need to manage ever more complex bodies of data, but they often do not have the money to purchase expensive hardware and software, let alone to hire a consultant to help them set up and run these systems.

Linux offers a solution to this problem. It transforms a typical 486- or Pentium-based PC into a multi-user workstation. It is free, and database tools available for it are either free or sold for a reasonable price.

Only one ingredient is missing from this recipe: the human expertise to design and program a relational database under Linux. This is where The Linux Database steps in. This book gives you a primer in designing and programming a relational database. If you are willing to invest sweat equity into your computer system, Linux will give you the tools you need to manage your organization’s data—and The Linux Database will teach you the skills you need to use those tools productively.

And as a bonus, you will acquire a skill that is becoming more marketable with every passing day.

Software Packages

The Linux Database comes with two relational database management systems:

•  Just Logic, a commercial database package provided with the permission of Just Logic Technologies, Montreal.

•  mSQL (miniature SQL), a commercial database package provided with the permission of Hughes Technologies, Gold Coast, Australia.

These packages were selected because they support a variety of tools and methods of input, yet are small, easy to install, and easy to use. You can use either or both of these packages to build relational databases on your Linux system.

Audience for This Book

The Linux Database gives Linux users a solid introduction to the craft of writing a relational database.

The book is in two parts:

•  Part I introduces relational databases. It discusses relational theory, database design, and structured query language (SQL).

•  Part II introduces programming a database application. It discusses how to code an interface with a relational database, using embedded SQL, ODBC, and JDBC; how to build a front end to a database using either CGI or Java; and the difficult subject of middleware.

Part I is aimed at persons who have not worked with relational databases. You will find it helpful regardless of whether or not you are a programmer.

Part II is aimed at persons who have some experience at programming. It assumes that you know the C programming language. The sections on Java assume that you at least know the rudiments of that language.

So, if you are a Linux user who wishes to build databases, or if you are database designer who wishes to learned about Linux or UNIX, or if you are a Linux or database programmer who wants to manage a database over the World Wide Web, then The Linux Database is for you.

If You Don’t Have Linux

This book’s example programs have been tested under Linux 1.2. If you do not yet have Linux on your system, we urge you to buy a copy of the book Linux Configuration and Installation, second edition, by Patrick Volkerding, Kevin Reichard, and Eric Foster-Johnson (New York, MIS:Press, 1996). Mr. Volkerding is the developer of Slackware.

This book is an excellent introduction to Linux: how to install it, how to configure it, and how to use it. It also comes with two CD-ROM disks, one of which contains the Slackware release of Linux. This release of Linux is compatible with the software included with this book.

A Final Word

We hope that The Linux Database will attract people to Linux who otherwise might not have considered using this operating system. In particular, we hope that more educators will consider using Linux as a teaching tool. We hope that The Linux Database will help to carry the gospel of Linux from the hacker community to the world at large.

We have tried our best to make this book and its software free of errors; however, as the writing of books is not yet totally automated, this package may well contain a bug or two. If you have any questions or complaints about The Linux Database, please e-mail your jeremiads and philippics (as well as your panegyrics) to ldb@lepanto.com.

Best wishes, and we hope you enjoy working with The Linux Database.