Question

我正在尝试编写触发器，我有以下表格： BookingRequest：

  +-----------+---------+------+-----+---------+----------------+
    | Field     | Type    | Null | Key | Default | Extra          |
    +-----------+---------+------+-----+---------+----------------+
    | idRequest | int(11) | NO   | PRI | NULL    | auto_increment |
    | roomClass | int(11) | NO   |     | NULL    |                |
    | inDate    | date    | NO   |     | NULL    |                |
    | outDate   | date    | NO   |     | NULL    |                |
    | numOfBeds | int(11) | NO   |     | NULL    |                |
    | status    | int(11) | NO   | MUL | NULL    |                |
    | idUser    | int(11) | NO   | MUL | NULL    |                |
    +-----------+---------+------+-----+---------+----------------+

状态表：

+------------+--------------------------------------------------+------+-----+---------+-------+
| Field      | Type                                             | Null | Key | Default | Extra |
+------------+--------------------------------------------------+------+-----+---------+-------+
| idStatus   | int(11)                                          | NO   | PRI | NULL    |       |
| nameStatus | enum('underConsideration','approved','rejected') | YES  |     | NULL    |       |
+------------+--------------------------------------------------+------+-----+---------+-------+

OccupiedRoom：

+--------------+---------+------+-----+---------+----------------+
| Field        | Type    | Null | Key | Default | Extra          |
+--------------+---------+------+-----+---------+----------------+
| idOccupation | int(11) | NO   | PRI | NULL    | auto_increment |
| idRoom       | int(11) | NO   |     | NULL    |                |
| idRequest    | int(11) | NO   |     | NULL    |                |
+--------------+---------+------+-----+---------+----------------+

我需要一个触发器，如果具有相同ID的请求被插入OccupiedRoom表中，它会将BookingReques中的状态更改为1，所以我尝试过这样的事情

create trigger occupy_trig after insert on OccupiedRoom 
for each row
begin
  if BookingRequest.idRequest= NEW.idRequest
   then
       update BookingRequest
       set status = '1';
       where idRequest = NEW.idRequest;

    end if;
END;

并且它不起作用，所以任何建议都会非常适合

Answer 1

试试这个：

DELIMITER $$
CREATE TRIGGER occupy_trig
AFTER INSERT ON `OccupiedRoom` FOR EACH ROW
begin
       DECLARE id_exists Boolean;
       -- Check BookingRequest table
       SELECT 1
       INTO @id_exists
       FROM BookingRequest
       WHERE BookingRequest.idRequest= NEW.idRequest;

       IF @id_exists = 1
       THEN
           UPDATE BookingRequest
           SET status = '1'
           WHERE idRequest = NEW.idRequest;
        END IF;
END;
$$
DELIMITER ;

Answer 2

根据您的要求，您的触发器中不需要BEGIN END和IF，并且不需要SELECT。所以你可以简化它到

CREATE TRIGGER occupy_trig AFTER INSERT ON occupiedroom 
FOR EACH ROW
  UPDATE BookingRequest
     SET status = 1
   WHERE idRequest = NEW.idRequest;

Answer 3

也许在设置之后删除分号，因为现在where语句不属于update语句。另外idRequest可能是个问题，最好写BookingRequest.idRequest

Answer 4

DELIMITER //

CREATE TRIGGER contacts_after_insert
AFTER INSERT
   ON contacts FOR EACH ROW

BEGIN

   DECLARE vUser varchar(50);

   -- Find username of person performing the INSERT into table
   SELECT USER() INTO vUser;

   -- Insert record into audit table
   INSERT INTO contacts_audit
   ( contact_id,
     deleted_date,
     deleted_by)
   VALUES
   ( NEW.contact_id,
     SYSDATE(),
     vUser );

END; //

DELIMITER ;

插入触发器之后的mysql更新另一个表的列

4 个答案: