删除加入错误

Question

执行此查询后：

 DELETE from  swimming_class as tb1 JOIN  (SELECT class_id FROM `swimming_class`
 left join swimming_school on swimming_school.school_id = swimming_class.school_id
 where swimming_school.school_name is NULL)  as temp ON temp.class_id = tb1.class_id

我收到此错误：

  

1064 - 您的SQL语法出错;查看与您的MySQL服务器版本对应的手册，以获得正确的语法，使用附近＆＃39;作为tb1 JOIN（SELECT class_id FROM swimming_class left join swim_school on＆＃39; at line 1

Answer 1

我认为你真正追求的是以下（SQL Fiddle）：

DELETE sc
FROM swimming_class sc
INNER JOIN swimming_school ss ON ss.school_id = sc.school_id
WHERE ss.school_name is NULL