Question

我需要平均一个字符而不是整数的列。例如，客户从我的公司...电话和互联网订购两种方式。我被要求获得所有订单的百分比。

Cust |  OrderType
-----------------
A    |  Phone
A    |  Phone
A    |  Phone
A    |  Internet
B    |  Internet
B    |  Internet
B    |  Phone

我如何提取这些数据并向我的经理表明，客户A 80％的时间通过电话订购，20％的时间通过互联网订购，客户B通过电话订购66％的时间和33％的互联网时间？

Answer 1

SELECT Cust,
SUM(CASE WHEN OrderType = 'Phone' THEN 1 ELSE 0 END) * 100 / COUNT(*)  'Phone percentage',
SUM(CASE WHEN OrderType = 'Phone' THEN 0 ELSE 1 END) * 100 / COUNT(*) 'Internet percentage'
FROM Table1 
GROUP BY Cust

Answer 2

您基本上希望订单总数除以每种订单的数量。

/*
create table #tmp (Cust CHAR(1), OrderType VARCHAR(10))

INSERT #tmp VALUES ('A', 'Phone')
INSERT #tmp VALUES ('A', 'Phone')
INSERT #tmp VALUES ('A', 'Phone')
INSERT #tmp VALUES ('A', 'Internet')
INSERT #tmp VALUES ('B', 'Internet')
INSERT #tmp VALUES ('B', 'Internet')
INSERT #tmp VALUES ('B', 'Phone')
*/

SELECT
     Cust, 
     OrderType, 
     (1.0 * COUNT(*)) / (SELECT COUNT(*) FROM #tmp t2 WHERE t2.Cust = t.Cust) pct,
     cast(cast(((1.0 * COUNT(*)) / (SELECT COUNT(*) FROM #tmp t2 WHERE t2.Cust = t.Cust) ) * 100 as int) as varchar) + '%' /* Formatted as a percent */
FROM #tmp t
GROUP BY Cust, OrderType

Answer 3

尝试下面的这个SQL

数据示例（此数据保存在临时表@temp中）

Cust  OrderType
----- --------------------------------------------------
A     Phone
A     Phone
A     Phone
A     internet
B     internet
B     internet
B     internet
B     Phone

SQL：

select Cust, OrderType, count(orderType)as float)*100/cast((select count(cust) 
from @temp where cust= a.cust) as Percentage from @temp a
group by cust,OrderType

结果：

Cust  OrderType                                          Percentage
----- -------------------------------------------------- ----------------------
A     internet                                           25
A     Phone                                              75
B     internet                                           75
B     Phone                                              25

注意：创建@temp

Declare @temp table
(
 Cust nvarchar(5),
 OrderType nvarchar(50)
)

insert into @temp values
('A','Phone'),
('A','Phone'),
('A','Phone'),
('A','internet'),
('B','internet'),
('B','internet'),
('B','internet'),
('B','Phone')

字符字段的平均值？

3 个答案: