Clean-Up: Delete datasets in the work library:

It is better always to clean-up/empty the work directory before we run the next set of SAS code. This is VERY helpful in situations where the �working� files created tend to use up a large amount of memory, once the logic of the program has been checked, KILLing the working files will result in a more efficient program. Another important reason to issue the above statement at the end of a program is when programs are run in batch, this will clean up the working library to be sure any �old� files are not left around to be erroneously used1.
 
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