mysql觸發器問題，我想刪除一個文章內容時另一個表中的有關這個文章的評論也同時刪除，這個怎麼寫？
delimiter //
create trigger tr_cno before delete on wenzhnag for each row
begin
delete from # begin
= delete from # begin
= delete from # begin
== old.content;
end;
# //
delimiter ;
###delete from pinglun where content='';######我本來是這樣寫的但是一直報錯誤######請這個怎麼寫####
