Well, your question "In the above program how many permanent and temporary data sets are read." - there is only one dataset "read", thats on the set line. The library sas is not shown however, so can't say about that. I also don't think the question is about "read" unless its a trick question. The reason is there are 3 datasets "written", one to temporary work area, 2 others are written to the physical library cert.