1
我想计算没有异常值的平均值(带有2个标准偏差)。我不断收到错误消息“聚合不应出现在WHERE子句中,除非它是在含有HAVING子句或选择列表在子查询中,并且被聚合的列是外部引用。如何计算没有异常值的平均值
select
b.[Location],
b.[txtOrderSubType],
avg (DATEDIFF(MINUTE, b.[dteActualStartDate], b.[dteActualEndDate])) as
[Avg Duration in min],
from dbo.tbl1
Where
DATEDIFF(MINUTE, b.[dteActualStartDate], b.[dteActualEndDate])< (
AVG(DATEDIFF(MINUTE, b.[dteActualStartDate], b.[dteActualEndDate]))+
2*STDEVP(DATEDIFF(MINUTE, b.[dteActualStartDate], b.[dteActualEndDate])))
and DATEDIFF(MINUTE, b.[dteActualStartDate], b.[dteActualEndDate])> (
AVG(DATEDIFF(MINUTE, b.[dteActualStartDate], b.[dteActualEndDate]))-
2*STDEVP(DATEDIFF(MINUTE, b.[dteActualStartDate], b.[dteActualEndDate])))
group by b.[Location], b.[txtOrderSubType]