diff --git a/set operator.sql b/set operator.sql
new file mode 100644
index 0000000..2ef902d
--- /dev/null
+++ b/set operator.sql	
@@ -0,0 +1,51 @@
+USE Study
+GO
+
+(SELECT * FROM EMPLOYEE WHERE DNO = 10)
+UNION
+(SELECT * FROM EMPLOYEE WHERE JOB = 'chief')
+
+(SELECT * FROM EMPLOYEE WHERE DNO = 10)
+INTERSECT
+(SELECT * FROM EMPLOYEE WHERE JOB = 'chief')
+
+(SELECT * FROM EMPLOYEE WHERE DNO = 10)
+EXCEPT
+(SELECT * FROM EMPLOYEE WHERE JOB = 'chief')
+
+-- Áߺ¹ Çã¿ë ÇÕÁýÇÕ
+(SELECT * FROM EMPLOYEE WHERE DNO = 10)
+UNION ALL
+(SELECT * FROM EMPLOYEE WHERE JOB = 'chief')
+
+-- ¿ÜºÎ ÇÕÁýÇÕ (ÇÕº´ ȣȯ¼º[: ¼Ó¼º °³¼ö ¹× ŸÀÔ ÀÏÄ¡] ºÒÀÏÄ¡ ÇÒ ¶§)
+(SELECT ENO, ENAME, DNO, NULL FROM EMPLOYEE)
+UNION
+(SELECT NULL, NULL, DNO, DNAME FROM DEPARTMENT)
+
+-- Áý´Ü ¿¬»êÀÚ
+SELECT AVG(SALARY) FROM EMPLOYEE
+
+SELECT MAX(SALARY) AS MAXSALARY, MIN(SALARY) AS MINSALARY FROM EMPLOYEE
+
+SELECT AVG(SALARY) AS AVERAGE, VAR(SALARY) AS VARIANCE, STDEV(SALARY) AS STANDARDDEVIATION FROM EMPLOYEE
+
+SELECT * FROM EMPLOYEE
+SELECT COUNT(*) AS NUMROW, COUNT(COMMISSION) FROM EMPLOYEE
+
+SELECT * FROM EMPLOYEE
+SELECT COUNT(JOB) AS JOB, COUNT(DISTINCT JOB) AS DISTJOB FROM EMPLOYEE
+
+SELECT DNO, AVG(SALARY) AS AVGSAL FROM EMPLOYEE GROUP BY DNO
+
+SELECT DNO, AVG(SALARY) AS AVGSAL FROM EMPLOYEE GROUP BY DNO HAVING MAX(SALARY) > 500
+
+SELECT DNO, JOB, AVG(SALARY) AS AVGSAL FROM EMPLOYEE GROUP BY DNO, JOB ORDER BY DNO
+
+SELECT DNO, JOB, AVG(SALARY) AS AVGSAL FROM EMPLOYEE GROUP BY DNO, JOB WITH ROLLUP
+
+SELECT DNO, JOB, AVG(SALARY) AS AVGSAL FROM EMPLOYEE GROUP BY DNO, JOB WITH CUBE
+
+SELECT DNO, JOB, AVG(SALARY) AS AVGSAL FROM EMPLOYEE GROUP BY GROUPING SETS (DNO, JOB) -- DNO, JOB µû·Î ÇÑ °ÍÀ» UNION Çؼ­ º¸¿©ÁÜ
+
+