头歌数据库 触发器

第1关：创建触发器-计算总学分

 use teachingdb;
 /****请在此编写代码，操作完毕之后点击评测******/
 
 /**********Begin**********/
 delimiter ##
  create trigger sum_credit
  after insert on score for each row
  Begin
  if(new.grade>=60) then
        update student set totalcredit =totalcredit+(select credit from course where cno=new.cno)
        where student.sno=new.sno;
    end if;
    end ##
    delimiter ;
 
  
 /**********End**********/

第2关：创建触发器-级联删除

 use teachingdb;
 /****请在此编写代码，操作完毕之后点击评测******/
 
 /**********Begin**********/
  delimiter ##
  create trigger del_studnet_score
  before delete on student for each row
  begin
    delete from score where sno=old.sno;
    end ##
  delimiter ;
 /**********End**********/