Matching data

[dapenDaniel]

Hello Experts,

I have two datasets as following below. I would like to know which observations are matched and unmatched. So I am going to create a dummy variable. 1 is coded If an observation is matched or exist in both datasets and 0 is coded if the observation is unmatched. Can anyone tell me how I can write the code? Thanks in advance!!!

Dataset1

ID1   ID2  Year

1      246   1990

12    359   1991

25    427   1993

Dataset2

ID1   ID2   Year

1      246   1990

6      531   1995

42    236   2002

25    427   1993

[PGStats · Accepted solution]

Assuming your datasets are sorted:

data want;
merge ds1(in=in1) ds2(in=in2);
by id1 id2 year;
flag = in1 and in2;
run;

(untested)

[dapenDaniel]

Thank you PG! You are the Best!!!!