如何從兩行的數據在SQL Server中查找單列記錄與AttTime

Question

我有查詢使用SQL Server 2005

我的考勤數據表結構是由兩排，第一AttTime和最後AttTime找到記錄單記錄：

EnrollNo Int 
AttDate  DateTime 
AttMonth Int 
AttDay  Int 
AttYear  Int 
AttTime  Varchar 

電流輸出：

EnrollNo  AttDate    AttMonth AttDay AttYear AttTime 
405 2011-03-09 09:59:00.000  9   3  2011  9:59  
405 2011-03-09 18:40:00.000  9   3   2011 18:40 

希望的輸出：

EnrollNo  AttDate    AttMonth AttDay AttYear FirstTime Last Time 
405 2011-03-09 09:59:00.000  9  3   2011  9:59  18:40 

Answer 1

假設你是分組記錄與同EnrollNo，你應該使用aggregate functions

SELECT EnrollNo, Min(AttDate), Min(AttMonth), Min(AttDay), Min(AttYear), Min(AttTime) as FirstTime, Max(AttTime) as LastTime  
    FROM AttLog 
    GROUP BY EnrollNo