php - 注册帐户时无法添加或更新子行

Question

我的网站上有一个注册表单，它将向客户发出一个 user_id(父表)，然后是成员表中的member_id。成员表引用父表，但似乎不会存储外键。我不确定如何解决这个问题，而且我对 sql 很陌生。

无法添加或更新子行:外键约束失败(gadgets.member, CONSTRAINT member_ibfk_1 FOREIGN KEY ( user_id) 引用 user (user_id) ON DELETE CASCADE ON UPDATE CASCADE)

Query: INSERT INTO member (first_name, last_name, address, city, post_code, phone, email, date) VALUES ('bob', 'all','33 wildown','london','n4','020','bob', NOW())

     CREATE TABLE IF NOT EXISTS `member` (
  `member_id` int(11) NOT NULL AUTO_INCREMENT,
  `first_name` varchar(32) NOT NULL,
  `last_name` varchar(32) NOT NULL,
  `address` varchar(60) NOT NULL,
  `city` varchar(32) NOT NULL,
  `post_code` varchar(32) NOT NULL,
  `phone` int(15) NOT NULL,
  `email` varchar(45) NOT NULL,
  `date` date NOT NULL,
  `user_id` int(11) NOT NULL,
  PRIMARY KEY (`member_id`),
  KEY `user_id` (`user_id`)
) ENGINE=InnoDB  DEFAULT CHARSET=latin1 AUTO_INCREMENT=20 ;

-- --------------------------------------------------------

--
-- Table structure for table `user`
--

CREATE TABLE IF NOT EXISTS `user` (
  `user_id` int(11) NOT NULL AUTO_INCREMENT,
  `username` varchar(30) NOT NULL,
  `password` varchar(30) NOT NULL,
  `type` enum('member','admin') NOT NULL DEFAULT 'member',
  PRIMARY KEY (`user_id`)
) ENGINE=InnoDB  DEFAULT CHARSET=latin1 AUTO_INCREMENT=19 ;

-- Constraints for table `member`
--
ALTER TABLE `member`
  ADD CONSTRAINT `member_ibfk_1` FOREIGN KEY (`user_id`) REFERENCES `user` (`user_id`) ON DELETE CASCADE ON UPDATE CASCADE;

/*!40101 SET CHARACTER_SET_CLIENT=@OLD_CHARACTER_SET_CLIENT */;
/*!40101 SET CHARACTER_SET_RESULTS=@OLD_CHARACTER_SET_RESULTS */;
/*!40101 SET COLLATION_CONNECTION=@OLD_COLLATION_CONNECTION */;

这是我的 php

if (empty($errors)) {//如果一切正常。

    // Register the user in the database...

    // Make the query:
    $q2 = "INSERT INTO user ( username, password) VALUES ('$un', SHA1('$p') )";
    $q = "INSERT INTO member (first_name, last_name, address, city, post_code, phone, email, date) VALUES ('$fn', '$ln','$a','$c','$pc','$pn','$e', NOW())";


    $r = @mysqli_query ($dbc, $q2);
    $r = @mysqli_query ($dbc, $q);

    // Run the query.
    if ($r) { // If it ran OK.

        // Print a message:
        echo '<h1>Thank you!</h1>
    <p>You are now registered.</p><p><br /></p>';   

    } else { // If it did not run OK.

        // Public message:
        echo '<h1>System Error</h1>
        <p class="error">You could not be registered due to a system error. We apologize for any inconvenience.</p>'; 

        // Debugging message:
        echo '<p>' . mysqli_error($dbc) . '<br /><br />Query: ' . $q . '</p>';

    } // End of if ($r) IF.

    mysqli_close($dbc); // Close the database connection.

    // Include the footer and quit the script:
    include ('includes/footer.html'); 
    exit();

} else { // Report the errors.

    echo '<h1>Error!</h1>
    <p class="error">The following error(s) occurred:<br />';
    foreach ($errors as $msg) { // Print each error.
        echo " - $msg<br />\n";

Answer 1

如果您要将其用作外键，则需要从第一个插入中检索 user_id 并将其包含在第二个插入中。您尝试在成员表中创建一条记录而不指定 user_id，但您的 CREATE 语句将其设置为 NOT NULL。