delete from student where id NOT in ( select min(id) id from student group by name,stuid,subid,subname,score );
当在mysql中执行这条语句时,报错:You can't specify target table 'student' for update in FROM clause;
原因是子查询中使用student表进行查询,而外层的delete语句也是对student进行的操作,因此报错。
解决办法:
将子查询再包装一次:
delete from student where id NOT in ( select * from ( select min(id) id from student group by name,stuid,subid,subname,score )a );
注意:这种错误只出现在mySQL中。
参考:http://blog.csdn.net/priestmoon/article/details/8016121