插入子 table 时触发将值插入父 table

Question

我有两个 table 结构如下。当我尝试添加到书籍 table 时，出现错误，提示我无法添加或更新我期望的子行。我希望在添加到书籍 table 之前，可以创建一个触发器将出版商名称添加到出版商 table。

这是我第一次使用触发器，我不确定自己做错了什么，也找不到示例。

create table publishers
    (name varchar(25) not null, 
    address varchar(55), 
    phone varchar(12),
    PRIMARY KEY(name)
    ) ENGINE = INNODB;

create table books
    (book_id int(4) not null auto_increment, 
    title varchar(40), 
    publisher_name varchar(25),
    primary key (book_id),
    foreign key (publisher_name) references publishers(name) ON UPDATE CASCADE ON DELETE CASCADE 
    ) ENGINE=INNODB;

以及我要创建的触发器：

DELIMITER ///
CREATE TRIGGER add_publisher BEFORE insert ON books
    FOR EACH ROW
    BEGIN
    INSERT INTO publishers(name) values (books.pubisher_name);
END;
///

DELIMITER ;

Answer 1

将books.publisher_name替换为NEW.publisher_name.

    DELIMITER ///
    CREATE TRIGGER add_publisher BEFORE insert ON books
        FOR EACH ROW
        BEGIN
        INSERT INTO publishers(name) values (NEW.publisher_name);
    END;
    ///
DELIMITER ;

插入子 table 时触发将值插入父 table

trigger to insert value into a parent table when inserting into the child table

mysql

triggers

mysql-error-1452