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|a Introduction, The two big questions to consider when buying a book are whetherr the book suits your needs and whether it can be easily understood. This introduction will let you know the book in a nutshell, including why I wrote it and how I think you should use it. My goal in this book is to make a comprehensive listing of dBASE II PLUS functions and commands, including the LAN functions and commands. My job is to be thorough. That isn't always easy with a program like dBASE III PLUS-there is an incredible amount the program can do, and an incredible amount you can do once you learn to program in dBASE III PLUS. The book provides detailed examples of the commands and functions as they are used in working dBASE III PLUS code. This should give you a better understanding of how each command or function is used as well as the advantages and disadvantages of its use. Ill cover the variety of ways you can use each command and function and how to make the most of what dBASE III PLUS can do. Question: Is this really a complete reference? Nothing is ever complete. This comes as close to complete as you'd like a reference to be and still be able to carry it under one arm. So, who is the b0ok for? It is for you, if 1. You want a thorough explanation of each dBASE III PLUS feature. 2. You want an information source that explains how each dBASE III PLUS command and function behaves in various situations 3. You don't have time to experiment 4. You're using dBASE III PLUS and need to get up to speed quickly 5. You have your own applications in mind and can't get them elsewhere 6. And, in particular, if you want examples of how commands and functions are used in working code, something not greatly developed in either the Ashton-Tate documentation or existing dBASE III PLUS books. Your best bet is to use this book as an information source, a quick reference to dBASE III PLUS commands and functions. Ideally, you'll use this book as a guide to proper dBASE III PLUS coding. You can go to the dBASE III PLUS documentation if you want a definition of a command or function, but you'll find that information here as well. This book is also a source of each command or function in working code. You'll be able to take the code blocks in this book and apply them to your applications with little or no modification. That should save you a great deal of work. At the same time, using the code blocks will force you to learn more about what dBASE III PLUS is as you make modifications to suit your own purposes. The first part of this book explains how III PLUS uses different file types, what each file is for, and how they work together. The second part deals with dBASE III PLUS commands. The command chapters are organized by purpose. You can probably find the information you need simply by analyzing what you're doing and then looking for applicable terms. For instance, if you want to change some data in a database, you are going to EDIT the data. The commands that are relevant to editing data are in the "Data Editing Commands" chapter. Selecting one particular record from the entire database involves LOCATING that one record. Commands relevant to locating a single record are grouped in the "Data Location Commands" chapter and include LOCATE, FIND, SEEK, CONTINUE, GOTO, n, and their variations. The last section of this book deals with the functions. Like the commands part of the book, the functions chapters are organized by purpose. All functions that deal with manipulating alphanumerics are found in the "String Functions" chapter. All functions that manipulate dates and time are found in the "TDate Functions" chapter. To use this book most effectively, you must know what you're trying to do with your application, so you can choose the correct commands and functions without having to experiment. lf you want to get up to speed as quickly as possible, you can order a disk containing all the code in this book. I've laid out the disk in subdirectories that correspond to the chapters and sections in this D0OK. You can acquire the disk by sending $17.50 (check only) to Northern Lights Consulting, P.0. Box 3861, Nashua, NH 03063-3861. Messages can be left for me on Compu Serve at #76137, 1300. -Joseph-David Carrabis.
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