blueran21 发表于 2016-2-18 12:30 
工作中用的兩種方法。
method 1:
Generally, we add Keep with Retain:
data A;
retain agegr1 agegr1n agrgr2 agegr2n agegr3 agegr3n;
keep agegr1 agegr1n agrgr2 agegr2n agegr3 agegr3n;
set B;
run;
The variable list can be easily got from:
proc contents data=BB varnum short; run;