无法使用PHP将用户添加到MySQL数据库，错误代码#1064

更新：

我最初的问题是关于向数据库中添加用户的问题。它已经解决了，但现在我在登录（login.php）时遇到了问题test@test.com，但当我尝试使用此电子邮件登录时，它显示"登录失败"。

我试图将最初问题的解决方案合并到login.php中，但代码似乎已经存在。所以我被卡住了。。。这是我的register.php页面和login.php页面。

我有一种感觉，不知何故，它与:email有关。我的login.php文件出了什么问题？

register.php

<?php 
    // First we execute our common code to connection to the database and start the session 
    require("common.php"); 
    // This if statement checks to determine whether the registration form has been submitted 
    // If it has, then the registration code is run, otherwise the form is displayed 
    if(!empty($_POST)) 
    { 
        // Ensure that the user has entered a non-empty username 
        if(empty($_POST['email'])) 
        { 
            // Note that die() is generally a terrible way of handling user errors 
            // like this.  It is much better to display the error with the form 
            // and allow the user to correct their mistake.  However, that is an 
            // exercise for you to implement yourself. 
            die("Please enter an email."); 
        } 
        // Make sure the user entered a valid E-Mail address 
        // filter_var is a useful PHP function for validating form input, see: 
        // http://us.php.net/manual/en/function.filter-var.php 
        // http://us.php.net/manual/en/filter.filters.php 
        if(!filter_var($_POST['email'], FILTER_VALIDATE_EMAIL)) 
        { 
            die("Invalid E-Mail Address"); 
        } 
      // Now we perform the same type of check for the email address, in order 
        // to ensure that it is unique. 
        $query = " 
            SELECT 
                1 
            FROM users 
            WHERE 
                email = :email 
        "; 
        $query_params = array( 
            ':email' => $_POST['email'] 
        ); 
        try 
        { 
            $stmt = $db->prepare($query); 
            $result = $stmt->execute($query_params); 
        } 
        catch(PDOException $ex) 
        { 
            die("Failed to run query: "); 
        } 
        $row = $stmt->fetch(); 
        if($row) 
        { 
            die("This email address is already registered"); 
        } 
        // An INSERT query is used to add new rows to a database table. 
        // Again, we are using special tokens (technically called parameters) to 
        // protect against SQL injection attacks. 
        $query = " 
            INSERT INTO users (  
                email 
            ) VALUES ( 
             :email 
            ) 
        "; 
        $query_params = array( 
        ':email' => $_POST['email'] 
    ); 
    try 
    { 
        $stmt = $db->prepare($query); 
        $result = $stmt->execute($query_params); 
    } 
    catch(PDOException $ex) 
    { 
        die("Failed to run query: "); 
    }  
        // This redirects the user back to the login page after they register 
        header("Location: login.php"); 
        // Calling die or exit after performing a redirect using the header function 
        // is critical.  The rest of your PHP script will continue to execute and 
        // will be sent to the user if you do not die or exit. 
        die("Redirecting to login.php"); 
    } 
?> 
<h1>Register</h1> 
<form action="register.php" method="post"> 
    E-Mail:<br /> 
    <input type="text" name="email" value="" /> 
    <br /><br /> 
    <input type="submit" value="Register" /> 
</form>

login.php

<?php 
    // First we execute our common code to connection to the database and start the session 
    require("common.php"); 
    // This if statement checks to determine whether the login form has been submitted 
    // If it has, then the login code is run, otherwise the form is displayed 
    if(!empty($_POST)) 
    { 
        // This query retreives the user's information from the database using 
        // their email. 
        $query = " 
            SELECT 
                email 
            FROM users 
            WHERE 
                email = :email 
        "; 
        // The parameter values 
        $query_params = array( 
            ':email' => $_POST['email'] 
        ); 
        try 
        { 
            // Execute the query against the database 
            $stmt = $db->prepare($query); 
            $result = $stmt->execute($query_params); 
        } 
        catch(PDOException $ex) 
        { 
            // Note: On a production website, you should not output $ex->getMessage(). 
            // It may provide an attacker with helpful information about your code.  
            die("Failed to run query: " . $ex->getMessage()); 
        } 
        // This variable tells us whether the user has successfully logged in or not. 
        // We initialize it to false, assuming they have not. 
        // If we determine that they have entered the right details, then we switch it to true. 
        $login_ok = false; 
        // Retrieve the user data from the database.  If $row is false, then the email
        // they entered is not registered. 
        $row = $stmt->fetch(); 
        // If the user logged in successfully, then we send them to the private members-only page 
        // Otherwise, we display a login failed message and show the login form again 
        if($login_ok) 
        { 
            // This stores the user's data into the session at the index 'user'. 
            // We will check this index on the private members-only page to determine whether 
            // or not the user is logged in.  We can also use it to retrieve 
            // the user's details. 
            $_SESSION['user'] = $row; 
            // Redirect the user to the private members-only page. 
            header("Location: private.php"); 
            die("Redirecting to: private.php"); 
        } 
        else 
        { 
            // Tell the user they failed 
            print("Login Failed.");   
        } 
    } 
?> 
<h1>Login</h1> 
<form action="login.php" method="post"> 
    Email:<br /> 
    <input type="text" name="email" value="My Email" /> 
    <br /><br /> 
    <input type="submit" value="Login" /> 
</form> 
<a href="register.php">Register</a>

谢谢！

您可以忽略下面的文本。

旧问题（适用于register.php）：

我正在尝试为我的网站创建一个简单的登录系统，注册/登录只需要一个电子邮件地址。当我尝试使用phpMyAdmin将用户添加到数据库时，会出现一个错误（详细信息如下）。

我已经成功创建了一个MySQL数据库使用：

CREATE TABLE `users` (
  `email` varchar(255) COLLATE utf8_unicode_ci NOT NULL,
  PRIMARY KEY (`email`)
) ENGINE=InnoDB  DEFAULT CHARSET=utf8 COLLATE=utf8_unicode_ci AUTO_INCREMENT=1;

然后在register.php页面上，我得到了这段代码。

<?php 
    // First we execute our common code to connection to the database and start the session 
    require("common.php"); 
    // This if statement checks to determine whether the registration form has been submitted 
    // If it has, then the registration code is run, otherwise the form is displayed 
    if(!empty($_POST)) 
    { 
        // Ensure that the user has entered a non-empty username 
        if(empty($_POST['email'])) 
        { 
            // Note that die() is generally a terrible way of handling user errors 
            // like this.  It is much better to display the error with the form 
            // and allow the user to correct their mistake.  However, that is an 
            // exercise for you to implement yourself. 
            die("Please enter an email."); 
        } 
        // Make sure the user entered a valid E-Mail address 
        // filter_var is a useful PHP function for validating form input, see: 
        // http://us.php.net/manual/en/function.filter-var.php 
        // http://us.php.net/manual/en/filter.filters.php 
        if(!filter_var($_POST['email'], FILTER_VALIDATE_EMAIL)) 
        { 
            die("Invalid E-Mail Address"); 
        } 
      // Now we perform the same type of check for the email address, in order 
        // to ensure that it is unique. 
        $query = " 
            SELECT 
                1 
            FROM users 
            WHERE 
                email = :email 
        "; 
        $query_params = array( 
            ':email' => $_POST['email'] 
        ); 
        try 
        { 
            $stmt = $db->prepare($query); 
            $result = $stmt->execute($query_params); 
        } 
        catch(PDOException $ex) 
        { 
            die("Failed to run query: "); 
        } 
        $row = $stmt->fetch(); 
        if($row) 
        { 
            die("This email address is already registered"); 
        } 
        // An INSERT query is used to add new rows to a database table. 
        // Again, we are using special tokens (technically called parameters) to 
        // protect against SQL injection attacks. 
        $query = " 
            INSERT INTO users (  
                email 
            ) VALUES ( 
             :email 
            ) 
        "; 

        // This redirects the user back to the login page after they register 
        header("Location: login.php"); 
        // Calling die or exit after performing a redirect using the header function 
        // is critical.  The rest of your PHP script will continue to execute and 
        // will be sent to the user if you do not die or exit. 
        die("Redirecting to login.php"); 
    } 
?> 
<h1>Register</h1> 
<form action="register.php" method="post"> 
    E-Mail:<br /> 
    <input type="text" name="email" value="" /> 
    <br /><br /> 
    <input type="submit" value="Register" /> 
</form>

问题可能是由以下代码引起的：

INSERT INTO users (  
                email 
            ) VALUES ( 
             :email 
            ) 

这是导致我在phpMyAdmin中出现问题的代码。它给了我这个错误：

#1064 - You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near ':email 
            )' at line 4 

register.php页面成功地连接到了我的数据库，并且也按照它应该的方式重定向了我，所以我觉得问题在于添加用户。