我有一个查询
Select AVG(((cast(c.rating1 as Float)+ cast(c.rating2 as Float)+cast (c.rating3 as Float)+cast(c.rating4 as Float)+cast(c.rating5 as Float))/5))
From CSEReduxResponses c
Where
c.execoffice_date BETWEEN DATEADD(MONTH, DATEDIFF(MONTH, 0, @today)-1, 0)
AND DATEADD(MONTH, DATEDIFF(MONTH, -1, @today)-1, -1)
AND c.execoffice_status =1
AND C.rating1 <> 0 AND C.rating2 <> 0 AND C.rating3 <> 0 AND C.rating4 <> 0 AND
C.rating5 <> 0
我得到了1-5的平均评分,但我也计算了等于'0'的评分。
我怎样才能让它只计算一个评级,其中评级[x]不等于'0' ?它仍然会计数,但除了除以5之外,它将除以非'0'的列数。
我创建了
这是不漂亮的但应该工作:
SELECT AVG((... SUM of 5 ratings ...) /
(CASE WHEN rating1 > 0 THEN 1 ELSE 0 END +
CASE WHEN rating2 > 0 THEN 1 ELSE 0 END +
CASE WHEN rating3 > 0 THEN 1 ELSE 0 END +
CASE WHEN rating4 > 0 THEN 1 ELSE 0 END +
CASE WHEN rating5 > 0 THEN 1 ELSE 0 END))
FROM ...
WHERE ...
在做了这样的事情之后,应该会对数据规范化感到感激。
尝试使用VALUES
获取每行非0值的平均值。
SELECT
(
SELECT AVG(rating)
FROM (VALUES
(cast(c.rating1 as Float)),
(cast(c.rating2 as Float)),
(cast(c.rating3 as Float)),
(cast(c.rating4 as Float)),
(cast(c.rating5 as Float))
) AS v(rating)
WHERE v.rating <> 0
) avg_rating
From CSEReduxResponses c
Where
c.execoffice_date BETWEEN DATEADD(MONTH, DATEDIFF(MONTH, 0, @today)-1, 0)
AND DATEADD(MONTH, DATEDIFF(MONTH, -1, @today)-1, -1)
AND c.execoffice_status = 1
http://sqlfiddle.com/!3/570fa/26
我从你的WHERE
中删除了以下条件
AND C.rating1 <> 0 AND C.rating2 <> 0 AND C.rating3 <> 0 AND C.rating4 <> 0 AND
C.rating5 <> 0
因为如果您留下它,您只计算具有5个非0评级的行的平均值,我猜这不是您的意图。
要得到所有行的非0评分的平均值,将所有非0评分的总和除以非0评分的总数。
SELECT
CAST(SUM(sum_rating) as float)/SUM(count_rating)
From CSEReduxResponses c
CROSS APPLY (
SELECT SUM(rating), COUNT(rating)
FROM (VALUES
(c.rating1),
(c.rating2),
(c.rating3),
(c.rating4),
(c.rating5)
) AS v(rating)
WHERE v.rating <> 0
) AS x (sum_rating, count_rating)
Where
c.execoffice_date BETWEEN DATEADD(MONTH, DATEDIFF(MONTH, 0, GETDATE())-1, 0)
AND DATEADD(MONTH, DATEDIFF(MONTH, -1, GETDATE())-1, -1)
AND c.execoffice_status = 1
http://sqlfiddle.com/!3/570fa/35
正如其他人提到的,如果可能的话,您应该考虑规范化您的表。