• mysql触发器关联表更新


    mysql> create table voteItem
        -> (
        ->  id INT NOT NULL AUTO_INCREMENT PRIMARY KEY,
        ->  title varchar(30),
        ->  ticketNumber int
        -> );
    Query OK, 0 rows affected (0.09 sec)
    
    mysql>
    mysql> create table ticket(
        ->  id INT NOT NULL AUTO_INCREMENT PRIMARY KEY,
        ->  voteItemID INT references voteItem(id) ,
        ->  ip varchar(30)
        -> );
    Query OK, 0 rows affected (0.09 sec)
    
    mysql>
    mysql> insert into voteItem values (null,'aaaaa',0);
    Query OK, 1 row affected (0.03 sec)
    
    mysql>
    mysql> select * from voteItem;
    +----+-------+--------------+
    | id | title | ticketNumber |
    +----+-------+--------------+
    |  1 | aaaaa |            0 |
    +----+-------+--------------+
    1 row in set (0.00 sec)
    
    mysql>
    mysql> DELIMITER |
    mysql>
    mysql> CREATE TRIGGER testref AFTER INSERT ON ticket
        ->   FOR EACH ROW BEGIN
        ->          update voteItem set ticketNumber=ticketNumber+1 where id = new.v
    oteItemID;
        ->   END;
        -> |
    Query OK, 0 rows affected (0.09 sec)
    
    mysql>
    mysql> DELIMITER ;
    mysql>
    mysql> insert into ticket values (null,1,'127.0.0.1');
    Query OK, 1 row affected (0.08 sec)
    
    mysql> select * from ticket;
    +----+------------+-----------+
    | id | voteItemID | ip        |
    +----+------------+-----------+
    |  1 |          1 | 127.0.0.1 |
    +----+------------+-----------+
    1 row in set (0.00 sec)
    
    mysql> select * from voteItem;
    +----+-------+--------------+
    | id | title | ticketNumber |
    +----+-------+--------------+
    |  1 | aaaaa |            1 |
    +----+-------+--------------+
    1 row in set (0.00 sec)

    摘自csdn论坛(http://bbs.csdn.net/topics/300203458)。

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  • 原文地址:https://www.cnblogs.com/fighter/p/3489539.html
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