Trigger para update before Insert

Question

My database has two tables, notification and attendance, as shown in the image.

In the notification table the default value of the status is "open".

I tried to make a Rigger that updates the default status "open" to "in attendance" after a new attendance table is inserted My Rigger ended up changing the status of all records in the notification table, and I want to change only the status of the notification that is referenced in the attendance table.

Below is the code of my Rigger

DELIMITER //
CREATE TRIGGER atualizanotificacao BEFORE INSERT ON atendimento
FOR EACH ROW
BEGIN
    UPDATE notificacao SET status = "Em atendimento" WHERE idnotificacao = idnotificacao;

END
// DELIMITER ;

Answer 1

It is changing all records because idnotification = idnotified is the same as 1 = 1. in all rows this condition would return true.

DELIMITER //
CREATE TRIGGER atualizanotificacao BEFORE INSERT ON atendimento
FOR EACH ROW
BEGIN
    UPDATE notificacao SET status = "Em atendimento" WHERE idnotificacao = NEW.idnotificacao;

END
// DELIMITER ;

This NEW which I added means that I will take the value of the notification that will be entered in the table meeting, or notification without the NEW is of the same notification table.