Question

我有一张存储披萨订单的表格。该表有一个名为quantity的值;特定顺序的比萨饼数量。我需要“创建一个查询，根据订单中的不同披萨数量分配订单。问题说明”您的SQL查询应该计算具有以下披萨数量的订单数量：1,2,3,4,5，研究了一段时间后，我想出了这个查询，但它没有按照我想要的方式工作。这是查询及其结果。提前致谢。

SELECT CASE 
    WHEN Quantity = 1 THEN '1 ' 
    WHEN Quantity = 2 THEN '2' 
    WHEN Quantity = 3 THEN '3 ' 
    WHEN quantity = 4 THEN '4' 
    WHEN quantity = 5 THEN '5 '  
    WHEN quantity = 6 THEN '6' 
    ELSE '>6' 
    END AS Range, COUNT(Quantity) AS Amount
FROM  orders
GROUP BY Quantity

输出：

Range     Amount
1         2
2         3
3         3
4         4
5         5
6         1
>6        1
>6        2
>6        2
>6        1

我如何分组＆gt; 6范围并计算金额。所以它在一个'＆gt; 6'条目下？

Answer 1

一种可能的方法是对CASE WHEN子句使用相同的GROUP BY语句，例如*：

SELECT CASE 
    WHEN Quantity <= 6 THEN CAST(Quantity as VARCHAR(1))
    ELSE '>6' 
    END AS Range, COUNT(Quantity) AS Amount
FROM  orders
GROUP BY (CASE 
    WHEN Quantity <= 6 THEN CAST(Quantity as VARCHAR(1))
    ELSE '>6' 
    END)

*）使用原始CASE WHEN语句的简化版本。用SQL Server的SQL Server风格编写。

Answer 2

运行此查询而不是之前的查询：

SELECT CASE 
WHEN Quantity = 1 THEN '1 ' 
WHEN Quantity = 2 THEN '2' 
WHEN Quantity = 3 THEN '3 ' 
WHEN quantity = 4 THEN '4' 
WHEN quantity = 5 THEN '5 '  
WHEN quantity = 6 THEN '6' 
ELSE '>6' 
END AS Range, COUNT(Quantity) AS Amount
FROM  orders
GROUP BY Range

Answer 3

选择IF（数量＆gt; 6，＆＃39;＆gt;＆＃39;，数量）AS范围，（数量*金额）AS金额来自订单

SQL Group按自定义范围？

3 个答案: