Separating Unique and Duplicate Observations Using PROC SORT in SAS 9.3 and Newer Versions

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Today, I stumbled upon a post where the author talks about a new options that are available in SAS 9.3 and later versions. These options (NOUNIQUEKEYS and UNIQUEOUT)  that allows sorting and then finding the duplicate records to be done in one step using PROC SORT.
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Separating Unique and Duplicate Observations Using PROC SORT in SAS 9.3 and Newer Versions

Christopher J. Bost published a paper in SAS Global Forum 2013 regarding the same option.


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