How to do a many-to-many merge in SAS without using SQL;
A many-to-many match-merge is more complicated. When we try to do many-to-many merge that means both the data sets have multiple occurrences of BY variable values. Simple match-merge the two data sets using the BY statement is never OK… Because when we do, we get the following note in the log. "NOTE: MERGE statement has more than one data set with repeats of BY values." SAS Programmer always tries to avoid this message in the log file….because this message means that the resulting data set is probably not what we expected. Don’t be afraid that there is no way… you can do many-to-many merge using data step. A well known SAS Expert David Franklin points out a way to do many-to-many merge Many Thanks David! (Read his original post here ) NS8PO19P The Fundamentals of MERGE