INNER JOIN 操作符

INNER JOIN 关键字在表中存在至少一个匹配时返回行。

SQL INNER JOIN 语法

SELECT column_name(s)
FROM table1
INNER JOIN table2
ON table1.column_name=table2.column_name;

或：

SELECT column_name(s)
FROM table1
JOIN table2
ON table1.column_name=table2.column_name;

注释：INNER JOIN 与 JOIN 是相同的 (交集)。

Demo

SELECT Customers.CustomerName, Orders.OrderID
FROM Customers
INNER JOIN Orders
ON Customers.CustomerID=Orders.CustomerID
ORDER BY Customers.CustomerName;

Mysql

也可以用上面的写法，等同下面

SELECT Customers.CustomerName, Orders.OrderID
FROM Customers , Orders
WHERE  Customers.CustomerID=Orders.CustomerID
ORDER BY Customers.CustomerName;