SAS Institute - SAS SQL procedure users guide: version 8

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Version 8

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The correct bibliographic citation for this manual is as follows: SAS Institute Inc., SASSQL Procedure User's Guide, Version 8, Cary, NC: SAS Institute Inc., 2000.

SASSQL Procedure User's Guide, Version 8

Copyright 2000 by SAS Institute Inc., Cary, NC, USA.

ISBN 158025599X

All rights reserved. Produced in the United States of America. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, or otherwise, without the prior written permission of the publisher, SAS Institute Inc.

U.S. Government Restricted Rights Notice. Use, duplication, or disclosure of this software and related documentation by the U.S. government is subject to the Agreement with SAS Institute and the restrictions set forth in FAR 52.22719 Commercial Computer Software-Restricted Rights (June 1987).

SAS Institute Inc., SAS Campus Drive, Cary, North Carolina 27513.

1st printing, April 2000

SAS and all other SAS Institute Inc. product or service names are registered trademarks or trademarks of SAS Institute Inc. in the USA and other countries.

IBM and all other International Business Machines Corporation product or service names are registered trademarks or trademarks of International Business Machines Corporation in the USA and other countries. indicates USA registration.

Other brand and product names are registered trademarks or trademarks of their respective companies.

The Institute is a private company devoted to the support and further development of its software and related services.

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What Is SQL?

What Is the SQL Procedure?

Terminology

Tables

Queries

Views

Null Values

Comparing PROC SQL with the SAS DATA Step

Notes about the Example Tables

Structured Query Language (SQL) is a standardized, widely used language that retrieves and updates data in relational tables and databases.

A relation is a mathematical concept that is similar to the mathematical concept of a set. Relations are represented physically as two-dimensional tables that are arranged in rows and columns. Relational theory was developed by E. F. Codd, an IBM researcher, and first implemented at IBM in a prototype called System R. This prototype evolved into commercial IBM products based on SQL. The Structured Query Language is now in the public domain and is part of many vendors' products.