新建一个触发器
实现：
当表1：ent_test的字段ent_status='3’时，
触发 表2：sand_grading插入一条数据。
总提示错误：

1064 - You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'IF NEW.ent_status='3'
       THEN
    INSERT INTO sand_grading

代码如下：

delimiter $$
create trigger insert_sg after update 
on ent_test for each row
begin
    IF  NEW.ent_status='3'
       THEN 
    INSERT  INTO sand_grading 
    (ent_number,model_code,test_status) 
   VALUES
(old.ENT_NUMBER,'A','1');
 end IF ;
 end$$