创建触发器Mysql

Question

将表Aluguel更新字段中的状态插入到忙后。

不工作。

DELIMITER $$ 
CREATE TRIGGER Tgr_Status_Update AFTER INSERT 
ON aluguel 
FOR EACH ROW 
    BEGIN 
     UPDATE apartamento SET status_apart = busy 
     WHERE id_apart = apartamento_id_apart; 
    END$$ 
DELIMITER ; 

Answer 1

，你必须使用新的关键字

DELIMITER $$ CREATE TRIGGER Tgr_Status_Update AFTER UPDATE 

ON aluguel FOR EACH ROW 

BEGIN UPDATE apartamento SET status_apart = new.busy 

WHERE id_apart = new.apartamento_id_apart; 

END$$ DELIMITER ; 

----------------------------- ----------插入触发器-----------------

DELIMITER $$ CREATE TRIGGER Tgr_Status_Insert AFTER INSERT 

ON aluguel FOR EACH ROW 

BEGIN UPDATE apartamento SET status_apart = new.busy 

WHERE id_apart = new.apartamento_id_apart; 

END$$ DELIMITER ; 

Answer 2

要引用要插入到表中的列，你需要使用NEW.column_name。

如果busy是一个字符串，则需要将其放在引号中。

DELIMITER $$ 
CREATE TRIGGER Tgr_Status_Update AFTER INSERT 
ON aluguel 
FOR EACH ROW 
    BEGIN 
     UPDATE apartamento SET status_apart = 'busy' 
     WHERE id_apart = NEW.apartamento_id_apart; 
    END$$ 
DELIMITER ; 

DEMO