SAS Certification Prep Guide, 4th Edition

Using Hash Objects as Lookup Tables

Overview

Beginning with SAS 9, the hash object is available for use in a DATA step. The hash object provides an efficient, convenient mechanism for quick data storage and retrieval.

Unlike an array, which uses a series of consecutive integers to address array elements, a hash object can use any combination of numeric and character values as addresses. Also unlike arrays, which return only a single value, hash objects can return multiple values from a given lookup. A hash object can be loaded from hardcoded values or a SAS data set, is sized dynamically, and exists for the duration of the DATA step.

The hash object is a good choice for lookups that use unordered data that can fit into memory because it provides ...