[code:l9i17jmk]data a;
input no$ x$;
cards;
001 aaa
001 bbb
002 ccc
002 ddd
002 eee
003 fff
;
data b(drop=x);
set a;
by no notsorted;
retain y;
if first.no then y=x;
else y=cats(y,x);
if last.no then output;
run;[/code:l9i17jmk]
[code:3e3twzmi]data _null_;
length y $50;
do _n_=1 by 1 until(last.no);
set a;
by no notsorted;
substr(y,length(y)+1)=x;
end;
put no= y=;
run;[/code:3e3twzmi]