Suppose you have the following table You need to find which Department has the maximum average salary in a single query you can easy ly find average value of each department using aggregate function AVG() But how to select only the department having the maximum average salary.In SQL SERVER USE select top 1 DeptName,MAX(MyAvg) AVARAGE_SALARY FROM( select AVG(salary) as MyAvg,DeptName from [SalaryTable] group by Deptname ) temp GROUP BY DeptName order by AVARAGE_SALARY desc
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