find intersection between two dates:

tsql find intersection between two dates

SELECT  DISTINCT   EHS.EmployeeID, MAX(CASE WHEN FromDate >= @DateFrom THEN FromDate ELSE @DateFrom END) AS Starts, 
													MAX(CASE WHEN ToDate  <= @DateTo	 THEN ToDate ELSE @DateTo END) AS Ends, E.Salaried, ISNULL(E.Salary, 0) as Salary
												FROM         EmployeeHolidaySickness EHS
													LEFT OUTER JOIN Employees E	ON EHS.EmployeeID = E.EmployeeID
												WHERE (RecordType = 'H') AND (FromDate <= @DateTo AND ToDate >= @DateFrom)
												GROUP BY EHS.EmployeeID,  E.Salaried, ISNULL(E.Salary, 0)