如何将用户输入与数据库匹配以进行验证码

Question

我开发了一个带有视频验证码的登录页面。现在登录功能完美无缺。

在此页面中，用户需要观看视频，然后在答案与数据库匹配后允许登录之前回答问题。

问题是如何使用数据库中的答案验证输入的答案。我的视频数据库表由ID | Video | question | answer

组成

require "config.php"; //Connection Script, include in every file! 

//Check to see if the user is logged in. 
if(isset($_SESSION['email'])){ 
   header("location: members.php"); //isset check to see if a variables has been 'set' 
} 



if(isset($_POST['submit'])) 
{ 
   //Variables from the table 
   $email  = $_POST['email']; 
   $password  = $_POST['password']; 

   //Prevent MySQL Injections 
   $email  = stripslashes($email); 
   $password  = stripslashes($password); 

   $email  = mysqli_real_escape_string($con, $email); 
   $password  = mysqli_real_escape_string($con, $password); 

   //Check to see if the user left any space empty! 
   if($email == "" || $password == "") 
   { 
      echo "Please fill in all the information!"; 
   } 

   //Check to see if the username AND password MATCHES the username AND password in the DB
   else 
   { 
      $query = mysqli_query($con,"SELECT * FROM detail WHERE email = '$email' and password = '$password'") or die("Can not query DB."); 
      $count = mysqli_num_rows($query); 

      if($count == 1){ 
         //YES WE FOUND A MATCH! 
         $_SESSION['email'] = $email; //Create a session for the user! 
         header ("location: members.php"); 
      } 

      else{ 
         echo "Username and Password DO NOT MATCH! TRY AGAIN!"; 
      } 
   } 

} 

?> 
                </span>
                <form action="login.php" method="post">

                    <label><b>Login</b>Not a member? <a href="http://localhost/captcha1/register.php"> Register </a> now!</label><br /><br />

                    <label>Email :<span>*</span></label><br />
                  <input name="email" type="text" id="email" placeholder="username@domain" required>
                    <br />

                    <label>Password :<span>*</span></label><br />
                    <input name="password" type="password" id="password"  placeholder="********"required>

                    <br />

</div>

<div style="float:right; width:50%; ">

    <?php
mysql_connect("localhost","root","");
mysql_select_db("details");
$res=mysql_query("select * from video ORDER BY RAND() LIMIT 1");



while($row=mysql_fetch_array($res))
{
?> 
<center><video width="360" height="270" controls><source src="**<?php echo $row["video"];?>**" type="video/mp4">

    </video><center>**<?php echo $row['question']; ?>**</center> </center>

 <input name="captcha" type="text" size"4" placeholder="" required><br>

</fieldset>

<br /><br />
                    <input  type="reset" value="Reset" />
                    <input type="submit" name="submit" value="Login">


                </form>

 <?php
}
?>