trigger mysql insert with key control code example

Example 1: Create Trigger in phpMyAdmin

DELIMITER &&
 
CREATE OR REPLACE TRIGGER tr_ajoutHotelResponsable
BEFORE INSERT ON cpoa.hotels
FOR EACH ROW
BEGIN
    IF(
        EXISTS(
            SELECT *
            FROM cpao.responsables
            WHERE numResponsable = NEW.numResponsable
        )
    )
    THEN
        UPDATE cpoa.responsables
        SET nbHotel = nbHotel + 1
        WHERE numResponsable = NEW.numResponsable;
    ELSE
        INSERT INTO cpao.responsables ( nom, prenom, nbHotels )
        VALUES ( 'nouveau', 'nouveau', 1 );
         
        SET NEW.numResponsable = LAST_INSERT_ID();
    END IF;
END&&
 
DELIMITER ;

Example 2: Create Trigger in phpMyAdmin

CREATE TRIGGER nomCltInsert
BEFORE INSERT ON client
FOR EACH ROW
    UPDATE client
    SET
        NEW.NomClient = UPPER(NEW.NomClient),
        NEW.PrenomClient = CONCAT( UPPER( LEFT(NEW.PrenomClient,1) ) , LOWER( SUBSTR( NEW.PrenomClient,2 ) ) );
 
CREATE TRIGGER nomCltUpdate
BEFORE UPDATE ON client
FOR EACH ROW
    UPDATE client
    SET
        NEW.NomClient = UPPER(NEW.NomClient),
        NEW.PrenomClient = CONCAT( UPPER( LEFT(NEW.PrenomClient,1) ) , LOWER( SUBSTR( NEW.PrenomClient,2 ) ) );