Question about if first...

[emoryustc]

Hi, all, I try to select a subground base on if first condition, but the following simple one is not working! nothing error in the log not no any obs output!  Anyone can help to see what's the reason? thanks 

data cars_sorted;
set cars;
if first.Make then output;
run;

[PaigeMiller · Accepted solution]

data cars_sorted;
set cars;
by make;
if first.Make then output;
run;