SQL:显示的小数比要求的小数多

这是我的代码

SELECT Concat(Round(SUM(Coalesce(Price.Morning, Price.Day, 
Price.Evening)*Tickets.count),2),' €') AS 'Total',
Concat(Round(SUM(Price.Morning * Tickets.count) * 100 / 
(SUM(Coalesce(Price.Morning, Price.Day, Price.Evening)*Tickets.count)),2),'%') 
AS 'Riti',
Concat(Round(SUM(Price.Day * Tickets.count) * 100 / 
(SUM(Coalesce(Price.Morning, Price.Day, Price.Evening)*Tickets.count)),2),'%') 
AS 'Dienas',
Concat(Round(SUM(Price.Evening * Tickets.count) * 100 / 
(SUM(Coalesce(Price.Morning, Price.Day, 
Price.Evening)*Tickets.count)),2),'%') 
AS 'Evening'
FROM Price,Tickets
WHERE Tickets.Price_ID = Price.Price_ID
;

它的显示方式如下：

---

一切正常，但逗号后我只需要2个小数，但它仍然显示2个以上。

不要在SQL中进行数字格式设置。让显示层（应用程序、报表、表单等）进行格式化。它限制了你适应不同文化、使用偏好等的能力

只需返回原始数据并删除格式：

SELECT
    SUM(Coalesce(Price.Morning, Price.Day, Price.Evening)*Tickets.count) AS 'Total',
    SUM(Price.Morning * Tickets.count) / 
        SUM(Coalesce(Price.Morning, Price.Day, Price.Evening)*Tickets.count) AS 'Riti',
    SUM(Price.Day * Tickets.count) / 
       SUM(Coalesce(Price.Morning, Price.Day, Price.Evening)*Tickets.count) AS 'Dienas',
    SUM(Price.Evening * Tickets.count) / 
       SUM(Coalesce(Price.Morning, Price.Day, Price.Evening)*Tickets.count AS 'Evening'
FROM Price,Tickets
WHERE Tickets.Price_ID = Price.Price_ID

您还可以通过将重复计算

合并（Price.Morning，Price.Day，Price.nighter）*Tickets.count

放入子查询中来简化此过程

round（）

更改值。强制转换为

decimal（）

，以更改类型。通常类型决定显示的内容。您使用的是哪种dbms？（该查询是特定于产品的。）