52.Given the SAS dataset WORK.EMP_NAME:
Name EmpID
---- -----
Jill 1864
Jack 2121
Joan 4698
John 5463
Given the SAS data setWORK.EMP_DEPT:
EmpID Department
----- ----------
2121 Accounting
3567 Finance
4698 Marketing
5463 Accounting
The following programis submitted:
data WORK.ALL;
merge WORK.EMP_NAME(in=Emp_N)
WORK.EMP_DEPT(in=Emp_D);
by Empid;
if (Emp_N and not Emp_D) or (Emp_D and notEmp_N);
run;
How many observationsare in data set WORK.ALL after submitting the program?
A. 1
B. 2
C. 3
D. 5
为什么选B,merge语句如何得到两个观测的?