mysql - 如何从sql中的连接中提取原始表

Question

with this database我做了下一个查询:

WITH comp_courses AS 
(SELECT * FROM course WHERE title LIKE "Comp%") 
SELECT * FROM (instructor INNER JOIN (comp_courses INNER JOIN teaches USING(course_id)) USING(ID));

现在返回一堆表的连接。但我想要的只是出现在讲师中的那个查询的列。关于如何做的任何想法？

Answer 1

您所要做的就是使用 * 运算符从该表中选择所有列，如下所示:

instructor.*

这应该能让您得到想要的结果:

SELECT 
  instructor.* 
FROM 
  instructor AS `i` 
  JOIN teaches AS `t` ON `t`.id = `c`.id 
  JOIN course AS `c` ON `c`.course_id = `t`.course_id
WHERE 
  `c`.title LIKE 'Comp%';

希望对您有所帮助，