Question

我试图将计数值除以子查询的值并乘以100以获得其百分比。以下代码有效......

SELECT data, rota as rt, COUNT(cliente_id) / 
(
 SELECT COUNT(DISTINCT cliente_id)
 FROM vw_grafico
 WHERE rota = rt  
) * 100 ) AS porcentagem

FROM vw_grafico
WHERE WEEKDAY(data)+1  = rota 
AND YEAR(data) = 2013
GROUP BY month(data)
ORDER BY data ASC

...但是，除此之外，我需要按月计算这个值的平均值，这就是我的问题......当我尝试这样做时，我有错误“无效使用组功能”：

SELECT data, rota as rt, AVG(COUNT(cliente_id) / 
(
 SELECT COUNT(DISTINCT cliente_id)
 FROM vw_grafico
 WHERE rota = rt  
) * 100 ) AS porcentagem

FROM vw_grafico
WHERE WEEKDAY(data)+1 = rota 
AND YEAR(data) = 2013
GROUP BY month(data)
ORDER BY data ASC

我该怎么做才能解决此错误？

Answer 1

Select list fields( not aggregates) must be Subset of Group by List that in your query this is not true and your error is for that.

在您的查询中：

SELECT data, rota as rt, AVG(COUNT(cliente_id) / 
(
 SELECT COUNT(DISTINCT cliente_id)
 FROM vw_grafico
 WHERE rota = rt  
) * 100 ) AS porcentagem

FROM vw_grafico
WHERE WEEKDAY(data)+1 = rota 
AND YEAR(data) = 2013
GROUP BY month(data)
ORDER BY data ASC

选择列表是：

data, rota as rt

和小组名单是：

month(data)

选择列表字段不是组列表的子集。所有选择列表字段必须在组列表中，例如：

SELECT month(data), rota as rt, AVG(COUNT(cliente_id) / 
(
 SELECT COUNT(DISTINCT cliente_id)
 FROM vw_grafico
 WHERE rota = rt  
) * 100 ) AS porcentagem

FROM vw_grafico
WHERE WEEKDAY(data)+1 = rota 
AND YEAR(data) = 2013
GROUP BY month(data), rota
ORDER BY data ASC

mysql中的平均百分比值

1 个答案: