DELIMITER $$
CREATE TRIGGER tg_prod BEFORE INSERT ON producto FOR EACH ROW
BEGIN
DECLARE num_row INTEGER;
SELECT COUNT (*) INTO num_row FROM producto WHERE substring (codigo,1,4)=year(new());
IF num_row = 0 THEN
set NEW codigo = CONCAT(year(new()),"-001");
ELSE
set NEW codigo = CONCAT(year(new()),’-’,(select lpad(cast(MAX(substring(codigo,6,8)) AS SIGNED)+1,3,‘0’)from producto where substring(codgo,1,4)=year(now())));
END IF
set NEW.dat_now=new();
END;
$$
ERRO: Mensagens do MySQL : 
#1064 - You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near 'SELECT COUNT (*) INTO num_row FROM producto WHERE substring (codigo,1,4)=yea' at line 5
