Provide data sample(s) and the desired result, in your post, for a more effective and timely response to your question. Also, to accomplish a MERGE in SAS, there are some data input requirements, depending on the desired results.
Below, you will find links to some SAS support website http://support.sas.com/ technical paper references for you to consider and review.
Scott Barry
SBBWorks, Inc.
http://www2.sas.com/proceedings/sugi27/p052-27.pdf
http://www2.sas.com/proceedings/sugi25/25/cc/25p109.pdf
Reading, Combining, and Modifying SAS Data Sets - SAS DOC with subsections to review:
http://support.sas.com/documentation/cdl/en/lrcon/59522/HTML/default/a001125856.htm
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