SQL请求3个链接表

Question

我有3个表：

，我想这样的结果：

我尝试用ORDER BY，但它没有工作， 有人有一个想法

Answer 1

你可以做一个INNER JOIN与GROUP BY，如：

SELECT s.number AS supplier, c.category AS category, s.date as `date`, COUNT(r.*) 
AS total 
FROM supplier s JOIN register r ON s.id = r.supplier_id 
JOIN category c ON c.id = r.category_id 
GROUP BY s.number, c.category, s.date; 

Answer 2

假设链接服务器名称为[LinkedSample \表] 然后你可以用下面的代码：什么对我来说似乎是一个非常

SELECT s.number AS supplier, c.category AS category, s.date as `date`, COUNT(r.*) AS total 
FROM [LinkedSample\Tables].supplier s 
JOIN [LinkedSample\Tables].register r ON s.id = r.supplier_id 
JOIN [LinkedSample\Tables].category c ON c.id = r.category_id 
GROUP BY s.number, c.category, s.date;