What are Select Groups?
Select Groups are another way SAS enables conditional processing of datasets.
When should we use Select Groups instead of if-then statements?
According to our friends at SAS, you should utilize Select Groups when your conditional criteria is mutually exclusive and numeric. When this is the case, Select Groups are more efficient than if-then processing.
Here are a few examples of conditional processing using Select Groups:
when (1) var2='YES';
when (2) var2='NO';
when (var1=1 and var2='JAN') var3='YES';
when (var1=2 and var2='FEB') var3='NO';