Using Indexes
Overview
An index can help you quickly locate one or more observations
that you want to read. Indexes provide direct access to observations
in SAS data sets based on values of one or more key variables. Index
applications include the following:
-
-
perform table lookup operations
-
join observations
Without an index, SAS
accesses observations sequentially, in the order in which they are
stored in a data set. For example, to access the observation in the
sample SAS data set shown below that has a value of
Smith
for the variable Name, SAS begins with the first observation and reads through each one until it reaches the observation that satisfies ...Get SAS Certification Prep Guide, 4th Edition now with the O’Reilly learning platform.
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