以下に説明するテーブルがあり、BEFORE INSERT トリガーを使用して列の値をセッション定義変数に更新しています。INSERT セットの modified_by_user 列と created_by_user 列の両方が期待どおり 1 に設定されます。しかし、UPDATE は、modified_by_user を期待どおりに 2 に変更せず、1 のままにします。どのように BEFORE UPDATE ON を使用して列の値を更新できますか? MySQL 5.5 を使用しています。ありがとう
SET @users_id=1;
INSERT INTO notes(notes,record_status_id,date_created) VALUES("hello","active",NOW());
//modified_by_user=1, created_by_user=1, notes="hello"
SET @users_id=2;
UPDATE notes SET notes="goodby" WHERE id=1;
//modified_by_user=1, created_by_user=1, notes="goodby"
CREATE TABLE IF NOT EXISTS `notes` (
`id` INT UNSIGNED NOT NULL AUTO_INCREMENT ,
`notes` TEXT NULL ,
`record_status_id` VARCHAR(8) NOT NULL ,
`date_created` DATETIME NOT NULL ,
`date_modified` TIMESTAMP NOT NULL ,
`modified_by_user` INT UNSIGNED NULL ,
`created_by_user` INT UNSIGNED NULL ,
PRIMARY KEY (`id`) ,
INDEX `fk_notes_users1_idx` (`modified_by_user` ASC) ,
INDEX `fk_notes_users2_idx` (`created_by_user` ASC) ,
INDEX `fk_notes_record_status1_idx` (`record_status_id` ASC) ,
CONSTRAINT `fk_notes_users10`
FOREIGN KEY (`modified_by_user` )
REFERENCES `users` (`id` )
ON DELETE NO ACTION
ON UPDATE NO ACTION,
CONSTRAINT `fk_notes_users20`
FOREIGN KEY (`created_by_user` )
REFERENCES `users` (`id` )
ON DELETE NO ACTION
ON UPDATE NO ACTION,
CONSTRAINT `fk_notes_record_status1`
FOREIGN KEY (`record_status_id` )
REFERENCES `record_status` (`id` )
ON DELETE NO ACTION
ON UPDATE NO ACTION)
ENGINE = InnoDB;
DELIMITER $$
CREATE TRIGGER tg_notes_ins BEFORE INSERT ON notes FOR EACH ROW
BEGIN
IF NEW.created_by_user IS NULL OR NEW.created_by_user = '' THEN
SET NEW.created_by_user = @users_id;
SET NEW.modified_by_user = @users_id;
END IF;
END$$
CREATE TRIGGER tg_notes_upd BEFORE UPDATE ON notes FOR EACH ROW
BEGIN
IF NEW.modified_by_user IS NULL OR NEW.modified_by_user = '' THEN
SET NEW.modified_by_user = @users_id;
END IF;
END$$
DELIMITER ;