MYSQL trigger trouble

Question

I want to make a trigger to do this:

UPDATE formulario 
    SET ano = EXTRACT(year FROM create_date),
    mes = EXTRACT(month FROM create_date) 

But i am getting a lot of trouble making it. it is accepted but doesn't work or gives away error message on posting new rows. I want to insert the create_date and get the ano and mes auto fitted. how can i do this ?

sorry here is the trigger defenition:

CREATE TRIGGER `anomes` AFTER INSERT ON `formulario` FOR EACH ROW BEGIN
UPDATE formulario SET ano = EXTRACT(year FROM create_date);
UPDATE formulario SET mes = EXTRACT(month FROM create_date); 
END;

and table:

-- Dumping structure for table at.formulario
CREATE TABLE IF NOT EXISTS `formulario` (
  `id` int(10) NOT NULL AUTO_INCREMENT,
  `uniqid` varchar(38) DEFAULT NULL,
  `create_date` date DEFAULT NULL,
  `ano` int(4) DEFAULT NULL,
  `mes` int(2) DEFAULT NULL,
  `codcliente` int(8) DEFAULT NULL,
  `tipo_act` int(1) DEFAULT NULL,
  `contacto_nome` varchar(50) DEFAULT NULL,
  `contacto_funcao` int(1) DEFAULT NULL,
  `contacto_telefone` varchar(20) DEFAULT NULL,
  `cara_cli_abc` int(1) DEFAULT NULL,
  `cara_cli_estado` int(1) DEFAULT NULL,
  `cara_cli_tipo_est` int(3) DEFAULT NULL,
  `cara_cli_sazonal` int(1) DEFAULT '0',
  `loc_inst_piso` varchar(5) DEFAULT NULL,
  `loc_inst_acesso` int(1) DEFAULT NULL,
  `loc_inst_data_vistoria` date DEFAULT NULL,
  `loc_inst_data_inter` date DEFAULT NULL,
  `loc_inst_time_vistoria_start` time DEFAULT NULL,
  `loc_inst_time_vistoria_end` time DEFAULT NULL,
  `loc_inst_time_inter_start` time DEFAULT NULL,
  `loc_inst_time_inter_end` time DEFAULT NULL,
  `check_list_p_agua` int(1) DEFAULT '0',
  `check_list_t_agua` int(1) DEFAULT '0',
  `check_list_p_dist` varchar(3) DEFAULT NULL,
  `check_list_obs` text,
  `final_obs` text,
  `vendedor` int(4) DEFAULT NULL,
  `dt_aceito` int(1) DEFAULT NULL,
  `bonus` text,
  `anulado` tinyint(1) DEFAULT '0',
  PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

Answer 1

The problem is that you cannot modify the table that invoked this trigger. It is a restriction.

Try to use a BEFORE INSERT trigger and set new values before the inserting data. For example:

CREATE TRIGGER anomes
BEFORE INSERT
ON formulario
FOR EACH ROW
BEGIN
  SET NEW.ano = EXTRACT(year FROM NEW.create_date);
  SET NEW.mes = EXTRACT(month FROM NEW.create_date); 
END

And the question - why are you going to store this data in the table? You can calculate it on the fly in SELECT query.