小编Mar*_*Aus的帖子

我正在努力使用正确的SQL语法来返回一列中特定值的计数.

此查询有效(可能语法不正确,但SQL Server 2008似乎很高兴)

SELECT StudentID, count(UnApproved)as Late, count(Unapproved) as Absent from results
WHERE unapproved=1 and StudentID in 
  (
    SELECT studentid  FROM [Results] 
    WHERE StudentYearLevel='10' and Date > 20130101) group by StudentID
  )

当然,由于'where'的位置,两个Late和Absent列都返回相同的值.

所以这是做(从右边)确定"10年级"成员的学生的ID.

然后,对于返回的每个学生ID,我需要它返回未经批准的缺席类型记录的未批准缺勤计数,并且在下一列中,还返回类型为2的未批准缺勤计数.

如果我尝试像这样提交查询: -

SELECT StudentID, count(UnApproved)as Late where unapproved=2, count(Unapproved) as Absent from results 
where unapproved=1 and StudentID in 
  (
    SELECT studentid  FROM [Results] where StudentYearLevel='10' and Date > 20130101
  )
group by StudentID

SQL Server破解了它,并以红色突出显示整个查询.

我需要最后这三列: -

StudentID | Late …