USE Study
GO

-- Çà¼ø¼­ ÇÔ¼ö

-- FISRT_VALUE: ù¹ø° Æ©Çø¸
SELECT DISTINCT DNO, FIRST_VALUE(SALARY) OVER (PARTITION BY DNO ORDER BY SALARY DESC) AS HIGH_SALARY
FROM EMPLOYEE

-- LAG/LEAD: Á¤·Ä ±âÁØ ¼±Çà/ÈÄÇà °ª Ãâ·Â
SELECT 
	DISTINCT ENAME, 
	SALARY, 
	LAG(SALARY, 1) OVER(ORDER BY SALARY DESC) AS LAG_SALARY,
	LEAD(SALARY, 1) OVER(ORDER BY SALARY DESC) AS LEAD_SALARY
FROM EMPLOYEE