In which case u go for libname and in which case u go for proc sql pass thru facilit diff?
1 SAS 3052data task; input id date date9. visit; cards; 101 01jan2015 1 101 02jan2015 2 101 06jan2015 3 102 04jan2015 1 102 07jan2015 2 102 12jan2015 3 103 06jan2015 1 103 13jan2015 2 ; run; write a program to find out missing dates between visits by each subject.
1 SAS 2346