Hands-On SAS for Data Analysis

Missing values

If there are a lot of missing values in the data, but it is still beneficial to create an index, use the Nomiss option. We will use the same dataset as used earlier in this chapter to create an index for Housing:

PROC DATASETS LIBRARY=WORK;MODIFY AC;      Index Create Housing / Nomiss;RUN;

This will ensure that the index is created successfully but that the missing values are not added to it. This will ensure that a lot of resources and space are saved in creating the index.

Be careful that BY processing or the WHERE clause will not use the index if the missing values are qualified in these statements. The program specified will still execute, but the index file will not be leveraged:

Data Subset;Set AC;Where Housing LT 88;Run; ...