sql group by,转换

时间:2012-05-19 05:41:36

标签: sql-server-2008

我的sql表中有两个bit类型的列用于员工出勤,以及1 for Medical Leave or 2 for Paid Leave之类的休假类型,其中的值类似,

FirstHalfLeave   Type      SecondHalfLeave  Type
 ------------    ----       -------------   ----
      0(Absent)   1             1             2
      1(Present)  1             1             2

我需要将这两个字段相加以使其离开一天,我需要显示确切的结果,如

  Type          Days
  ----         ------
MedicalLeave     0.5
PaidLeave        1.0

为此我尝试了

select cast(
       sum(
             (
               CAST(StaffAttendance.FirstHalfStatus as Integer) + 
               CAST(StaffAttendance.SecondHalfStatus as integer)
             ) 
             / 2.0
       ) as float
   ) as TotalLeave
   ,case when StaffAttendance.FirstHalfLeaveType = 2 OR 
StaffAttendance.SecondHalfLeaveType=2 then 'Paid Leave'
   else 'Medical Leave'
   end as Status
from StaffAttendance
where MONTH(StaffAttendance.date)=MONTH(GetDate())
group by StaffAttendance.FirstHalfLeaveType,StaffAttendance.SecondHalfLeaveType

但它没有分组,我不知道如何做到这一点,任何人都可以帮助我,在此先感谢

1 个答案:

答案 0 :(得分:2)

SELECT SUM(sa.LeaveDays)/COUNT(sa.LeaveDays),sa.Status
FROM
    (
        SELECT CAST(FirstHalfStatus AS FlOAT) LeaveDays,CASE WHEN FirstHalfLeaveType=2 THEN 'Paid Leave' ELSE 'Medical Leave' END as Status,date
        FROM StaffAttendance        
        UNION ALL
        SELECT CAST(SecondHalfStatus AS FlOAT),CASE WHEN SecondHalfLeaveType=2 THEN 'Paid Leave' ELSE 'Medical Leave' END as Status,date
        FROM StaffAttendance
    ) AS sa
WHERE MONTH(sa.date)=MONTH(GetDate())   
GROUP BY sa.Status