php - Adding new record to database prevents echoing other records -


hi have created forum website logged in users can create topics using form on each forum topic, when add new record using form prevents , previous topics being displayed.

i have no idea why , greatful help. have forum page displays categories, topics(if category selected) , replies (if topic selected). here code forum.php page

    <div id="midclmn">     <?php      if (isset($_get['topic'])){          // show topic & replies          $queryreply = "select a.reply_id,a.reply_text, a.reply_date, b.topic_title, b.topic_date,c.username reply_user, (select username users          user_id=b.user_id) topic_creator forum_replies          left join forum_topics b on a.topic_id=b.topic_id         left join users c on a.user_id=c.user_id                  a.topic_id = '".$_get['topic']."'    ";                        $result = mysql_query($queryreply) or die (mysql_error());                         $row = mysql_fetch_array($result);                          if(empty($row['reply_id'])){                         echo "no replies have been posted in topic, first have using form below.";} ?>            <table id="categorytable">                  <tr><td><?php echo '<b>'.$row['topic_title'].'</b>';?></b><br></td></tr>                 <tr><td><?php echo 'topic published '.$row['topic_creator'].' - ( '.$row['topic_date'].' )'.'';?><br><br></td></tr>                 <tr><td><?php $row['reply_user'].' replied with: ';?><br></td></tr>                 <tr><td><?php echo $row['reply_text'].'<br><br><i>published:  '.$row['reply_date'].'    '.$row['reply_user'].'</i>';?></td></tr>                 <?php                  while ($row = mysql_fetch_array($result)){ ?>                  <tr><td><?php $row['reply_user'].' replied with: ';?><br></td></tr>                 <tr><td><?php echo $row['reply_text'].'<br><br><i>published:  '.$row['reply_date'].'    '.$row['reply_user'].'</i>';?></td></tr>               <?php                } ?>             </table>                 <?php          }elseif (isset($_get['cat'])){         // show topics in category           $querytopic = "select topic_id, topic_title,topic_description, topic_date, category_id forum_topics category_id = '".$_get['cat']."'";         $result = mysql_query($querytopic) or die (mysql_error());         $row = mysql_fetch_array($result);           if(empty($row['topic_id'])){             echo "no topics have been posted in category, first submit topic using form below."; ?>         <table id="categorytable">                 <tr><td><?php echo '<a href="forum.php?topic='.$row['topic_id'].'&cat='.$row['category_id'].'"><b>'.$row['topic_title'].'</b></a>';?></td></tr>                 <tr><td><?php echo $row['topic_description'];?><br><br></td></tr>                 <tr><td><?php echo "<b>date posted:</b>   ".$row['topic_date'];?><br><br></td></tr>             <?php                  while ($row = mysql_fetch_array($result)){ ?>                     <tr><td><?php echo '<a href="forum.php?topic='.$row['topic_id'].'&cat='.$row['category_id'].'"><br>'.$row['topic_title'].'</b></a>';?></td></tr>                     <tr><td><?php echo $row['topic_description'];?><br><br></td></tr>                     <tr><td><?php echo "<b>date posted:</b>   ".$row['topic_date'];?><br><br></td></tr>               <?php                }} ?></table><?php                 if($_session['loggedin'] === true){                     $userid = $_session['id'];                     $catid = $_get['cat'];                      ?>              <br>             <form method="post" action="topic_process.php" id="topicform">                 <h3>add new topic</h3>             <input type="hidden" id="catid" name="catid"  value=<?php echo $catid?> >              <input type="hidden" id="userid"    name="userid"  value=<?php echo $userid ?>>               <label for="topictitle">topic title:&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</label>             <textarea rows="2" cols="80"  id="topictitle" name="topictitle"  required ></textarea>                 <br><br>             <label for="topicdescription">topic description:&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</label>             <textarea  rows="10" cols="80" id="topicdescription" name="topicdescription"   required ></textarea>             <input type= "hidden" id="topicdate" name="topicdate" value=<?php echo ''.date('y-m-d').'' ?>>                  <br><br>                 <input type="submit" name="topicsubmit" id="topicsubmit" value="create topic">               </form>  <?php                 } ?>            <?php            }else{          //just display list of categories         $querycategory = "select category_id, category_title,category_description forum_category";         $result = mysql_query($querycategory) or die (mysql_error());         $row = mysql_fetch_array($result); ?>          <table id="categorytable">                 <tr><td><?php echo '<a href="forum.php?cat='.$row['category_id'].'">'.$row['category_title'].'</a>';?></td></tr>                 <tr><td><?php echo $row['category_description'];?><br><br></td></tr>             <?php                  while ($row = mysql_fetch_array($result)){ ?>                     <tr><td><?php echo '<a href="forum.php?cat='.$row['category_id'].'">'.$row['category_title'].'</a>';?></td></tr>                     <tr><td><?php echo $row['category_description'];?><br><br></td></tr>               <?php                }                 ?>             </table> <?php   }    ?>  </div> 

and here process page

session_start(); include "includes/connection.php";  echo $_post['topictitle']; echo $_post['topicdescription']; echo $_post['userid']; echo $_post['catid'];     $query = "insert forum_topics (     category_id,     user_id,     topic_title,     topic_description,     topic_date     ) values     (     '".$_post['catid']."',     '".$_post['userid']."',     '".$_post['topictitle']."',     '".$_post['topicdescription']."',     '".$_post['topicdate']."'     )";      mysql_query($query) or die (mysql_error()); header('location: /test/forum.php?'.$_post['catid'].'');   ?> 

i struggling record topic_date today's date tried date('y-m-d') 2015-04-28 saved 00-00-00.

i know lot of code read i'm stuck , don't want miss anything, know mysql_functions deprecated have been asked use them uni.

im using phpmyadmin database, know rubbish!

edit: have set page displays topics stored in database (topic_title, topic_description, user_id, topic_date). before add new topic database works fine afterwards topics including new 1 disappear leaving form on page. records still exist on database , deleting new record brings topics displayed on page.