How to remove duplicated records\observations WITHOUT sorting in SAS？

I wonder if there is a way to unduplicate records WITHOUT sorting?Sometimes, I want to keep original order and just want to remove duplicated records.

Is it possible?

BTW, below are what I know regarding unduplicating records, which does sorting in the end..

1.

proc sql;
   create table yourdata_nodupe as
   select distinct *
   From abc;
quit;

2.

proc sort data=YOURDATA nodupkey;    
    by var1 var2 var3 var4 var5;    
run;