SQL Server 2012 에서 행을 비교할때 사용할수있는 함수입니다. 1. 원본데이터 SELECT ProductID, ModifiedDate, StandardCost FROM Production.ProductCostHistory WHERE ProductID IN (711, 712, 713) ORDER BY ProductID, ModifiedDate 2. LAG/LEAD 함수 SELECT ProductID, StandardCost, ModifiedDate, LAG(StandardCost, 1, NULL) OVER (PARTITION BY ProductID ORDER BY ModifiedDate) AS PrevStandardCost, LEAD(StandardCost, 1, NULL) OVER (PARTI..