SAS® Certification Prep Guide: Advanced Programming for SAS®9, Third Edition

Chapter 21Controlling Data Storage Space

Overview

Introduction

Objectives

Prerequisites

Reducing Data Storage Space for Character Variables

How SAS Assigns Lengths to Character Variables

Reducing the Length of Character Data with the LENGTH Statement

Other Techniques

Reducing Data Storage Space for Numeric Variables

How SAS Stores Numeric Variables

Assigning Lengths to Numeric Variables

Example

Maintaining Precision in Reduced-Length Numeric Variables

Using PROC COMPARE

Example

Comparative Example: Creating a SAS Data Set That Contains Reduced-Length Numeric Variables

General Recommendations

Compressing Data Files

Overview

Review of Uncompressed Data File Structure

Compressed Data File Structure

Deciding Whether to Compress a Data File

The COMPRESS= ...