MYSQL：在TRIGGER中出现错误

Question

I want trigger which function is - before update of product table if price value is changed then copy that row to product_log table. I want this functionality to manage log of product price.

This is my product table

#   Name            Type    
1   id              int(11) 
2   name            varchar(100)
3   price           bigint(20)
4   created_date    datetime

This is my product_log table

#   Name            Type    
1   id              int(11) 
2   name            varchar(100)
3   price           bigint(20)
4   created_date    datetime
5   is_procced      int(11)

This is my trigger -

CREATE TRIGGER pro_log BEFORE UPDATE ON product
 FOR EACH ROW
 BEGIN
     IF (OLD.price != NEW.price)
     THEN
        INSERT INTO product_log (SELECT *, 1 FROM product WHERE id = OLD.id);
     END IF;
 END;

I am getting this error - #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 '' at line 6

Answer 1

You need to change the delimiter. Otherwise the trigger definition ends at the first semicolon which would make it incomplete.

delimiter |
CREATE TRIGGER pro_log BEFORE UPDATE ON product
 FOR EACH ROW
 BEGIN
     IF (OLD.price != NEW.price)
     THEN
        INSERT INTO product_log 
        SELECT *, 1 FROM product WHERE id = OLD.id;
     END IF;
 END
|
delimiter ;