title: php if statement (how to check the user input duplicate record)
body: <p>how to check the input between users and database whether it is duplicate?
  This is the form for the user to input data to database
  And This code's result will be work whether it saves same or not same records.
      
  
  <pre><code>    $con = mysql_connect("localhost","root","usbw");
      if (!$con)
        {
        die('Could not connect: ' . mysql_error());
        }
      mysql_select_db("booking", $con);
  
      $year = $_POST['year'];
      $month = $_POST['month'];
      $day = $_POST['day'];
      $time = $_POST['time'];
      $classroom = $_POST['classroom']; 
      $subject = $_POST['subject'];
      $s=implode(" ",$subject);
      $sql1 = "SELECT * FROM `test` WHERE `year` LIMIT 0, 30 ";
      $result=mysql_query("$sql1");
      $row =mysql_fetch_row($result);
  
  
  
  
          $sql = "INSERT INTO `test`(`year`, `month`, `day`, `time`, `classroom`,`subject`) VALUES  ('$year','$month','$day','$time','$classroom','$s')";
  
  
  
      ?&gt;
  </code></pre>
  
  <p>I wrote a code that I think that can determine the same records
  if same , user can not input.
  if not same user can input.
  The code represent like this :</p>
  
  <p>　</p>
  
  <pre><code>if($row[1]==$year){ 
  　   echo'the data was repeated';
  </code></pre>
  
  <p>can anyone help to solve my if-statement problem?</p>
  
  <p>Update:</p>
  
  <pre><code>if($row[1]==$year){ 
  　   echo'the data was repeated';} else{
      $sql = "INSERT INTO `test`(`year`, `month`, `day`, `time`, `classroom`,`subject`) VALUES  ('$year','$month','$day','$time','$classroom','$s')";}
  </code></pre>
  
  <p>I wrote this syntax error....(Parse error: syntax error, unexpected '@' in )
  Should I use While-loop to rewrite?
  Could you please  tell me how to correct the code?</p>