按语句编写特定的SQL组

Question

我有一张表格，我已将其截图并上传到此处：

我需要创建一个sql查询来计算具有以下披萨数量的订单数量：1,2,3,4,5,6及以上6.

我已经尝试过一些SQL语句，但还没找到合适的语句。

我目前的尝试是

<asp:SqlDataSource ID="SqlDataSource1" runat="server" 
            ConnectionString="<%$ ConnectionStrings:ConnectPizza %>" 
            SelectCommand="Select '1' AS Caption, Count(quantity) AS Count FROM orders WHERE quantity = 1 
            UNION ALL
            Select '2' AS Caption, Count(quantity) AS Count FROM orders WHERE quantity = 2
            UNION ALL
            Select '3' AS Caption, Count(quantity) AS Count FROM orders WHERE quantity = 3
            UNION ALL
            Select '4' AS Caption, Count(quantity) AS Count FROM orders WHERE quantity = 4
            UNION ALL
            Select '5' AS Caption, Count(quantity) AS Count FROM orders WHERE quantity = 5
            UNION ALL
            Select '6' AS Caption, Count(quantity) AS Count FROM orders WHERE quantity = 6
            UNION ALL
            Select 'Above 7' AS Caption, Count(quantity) AS Count FROM orders WHERE quantity > 7">
        </asp:SqlDataSource>  

但它没有成功。

我也想创建一个图表，但即使我的sql语句成功，我也不确定我为X和Y值成员输入的内容。

任何帮助都将不胜感激。

Answer 1

这将按您希望的方式分配您的数量，然后将数量计数分组1-7。我没有在组中使用该案例，因为在许多数据库中不允许这样做。

Select o.quantity AS Caption, Count(o.quantity) AS Count 
FROM (SELECT CASE WHEN quantity < 7 THEN Quantity ELSE 7 END) quantity from orders) o 
group by o.quantity

Answer 2

这应该会让你接近，但会将所有7个以上的数量标记为“7”

select  case when quantity < 7 then quantity else 7 end,
        count(*)
from    orders
group by case when quantity < 7 then quantity else 7 end

要使7+标签正确，需要确切知道您正在使用的SQL变体