SQL inner join内联接

INNER JOIN 关键字语法

SELECT column_name(s)
FROM table_name1
INNER JOIN table_name2
ON table_name1.column_name=table_name2.column_name

题目：

请编写 SQL 语句，将课程表 courses 和教师表 teachers 进行内连接，查询 “Eastern Heretic” 老师所教的所有课程的课程名和课程编号 , 且结果列名分别以课程编号 id 、课程名称 course_name 和教师姓名 teacher_name 显示。

错误写法：

    SELECT courses.id,courses.courses_name,teachers.teacher_name
    FROM teachers
    INNER JOIN courses
    ON courses.id = teachers.id where teachers.teacher_name =  “Eastern Heretic”

正确写法：

    SELECT c.id,c.name as course_name,t.name as teacher_name
    FROM teachers t
    inner join courses c on c.teacher_id=t.id
    WHERE t.name=’Eastern Heretic’