Create a column with name of datasets you are stacking

[mariko5797]

I know there's a way to do this but I cannot remember what the option is called and am also having trouble looking it up.

I essentially want to stack multiple datasets and have a column created with their names in it so I can keep track of which data belongs to which dataset.

data have1;
 var1 = 'A'; var2= 'BC'; var3= 1;
data have2;
 var1 = 'D'; var2= 'EF'; var3= 2;
data have;
 set have1 have2;
run;

data want;
 input dsn $ var1 $ var2 $ var3 @@;
 cards;
 have1 A BC 1
 have2 D EF 2
 ;
run;

[Reeza · Accepted solution]

 Use the INDSNAME (Input DataSet Name) option

data have;
    length source src $40.;
    set have1 have2 indsname = source;
    src=source;
run;

[PeterClemmensen]

Check out Where did it come from? Adding the source of each observation to a SAS data set by Rick Wicklin.