How to get table C in the easiest way?

[zhangda]

Hi,

A quick question, what is the easiest way to get table C where only two columns there, num=5 and index=a, thanks!

data A;
input num index $;
cards;
1 a
2 a
3 a
4 a
;
run;

data B;
input num index $;
cards;
1 a
2 a
3 a
4 a
5 a
;
run;

[ballardw]

What does C look like? What does it come from?

Easiest from your description might well be:

data c;
input num index $;
cards;
;
run;

so I think you are missing some details of your issue.

[Astounding]

Sort your data sets if they are not already in order:

proc sort data=a; by num index; run;

proc sort data=b; by num index; run;

In this case, your data sets are already in order and don't need to be sorted.  

Then to find the mismatch:

data c;

merge a (in=in_a)  b (in=in_b);

by num index;

if in_a=0;

run;

In this case, the program doesn't actually need IN_A.  But your real requirements might be to find mismatches in either direction where you might use:

if in_a=0 or in_b=0;