Question

我现在一直试图写这个查询2个小时。请帮忙。

问题和＃34; Jamba Juice已经下了多少订单＆＃34;？

这就是我所拥有的。

SELECT 
    Customers.customerNumber, Customers.customerName, 
    COUNT(orderNumber) AS orders_placed
FROM 
    Customers
WHERE 
    Customers.customerName = 'Jamba Juice'
JOIN 
    Orders ON Customers.customerNumber = Orders.customerNumber
GROUP BY 
    Customers.customerNumber, Customers.customerName;

我得到的错误信息是

Msg 156，Level 15，State 1，Line 29
关键字＆＃39; JOIN＆＃39;
附近的语法不正确

Answer 1

Join应该在WHERE之前。

SELECT Customers.customerNumber, Customers.customerName, COUNT(orderNumber) AS orders_placed
FROM Customers
JOIN Orders ON Customers.customerNumber= Orders.customerNumber
WHERE Customers.customerName= 'Jamba Juice'
GROUP BY Customers.customerNumber, Customers.customerName;

Answer 2

您的JOIN声明应该在FROM Customers之后和where子句

之前

SELECT Customers.customerNumber, Customers.customerName, COUNT(orderNumber) AS orders_placed

FROM Customers

JOIN Orders ON Customers.customerNumber= Orders.customerNumber

WHERE Customers.customerName= 'Jamba Juice'

GROUP BY Customers.customerNumber, Customers.customerName;

Answer 3

似乎语法错误。请注意表格需要首先加入，然后加入条件和过滤条件，如下所示。

SELECT Customers.customerNumber, Customers.customerName, COUNT(orderNumber) AS orders_placed
FROM Customers
JOIN Orders ON Customers.customerNumber= Orders.customerNumber
WHERE Customers.customerName= 'Jamba Juice'
GROUP BY Customers.customerNumber, Customers.customerName;

SQL Server：＆＃34; Jamba Juice已经下了多少订单＆＃34;？多对多的关系

3 个答案: