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echo '<a class="bg-danger btn btn-default" href="index.php" '; 
global $post, $wpdb;
 if( !isset($_GET['char']) ){
  echo ' class="active" ';
 }
 echo ' >All</a></li>';
 // Select Alphabets and total records
 $alpha_sql = "select DISTINCT LEFT(title , 1) as firstCharacter,
  ( select count(*) from products where LEFT(title , 1)= firstCharacter ) AS counter 
  from products 
  order by title asc";
 $result_alpha = mysqli_query($wpdb->dbh,$alpha_sql);
 while($row_alpha = mysqli_fetch_array($result_alpha)){
  $firstCharacter = $row_alpha['firstCharacter'];
  $counter = $row_alpha['counter'];
  echo '<a class="btn btn-default" href="?char='.$firstCharacter.'" '; 
  if( isset($_GET['char']) && $firstCharacter == $_GET['char'] ){
   echo ' class="active" ';
  }
  echo ' >'.$firstCharacter.'</a></li>';
 }
 ?>
  <?php
  // selecting rows
  $sql = "SELECT * FROM products where 1"; 
  if( isset($_GET['char']) ){
   $sql .= " and LEFT(title,1)='".$_GET['char']."' ";
  }
  $sql .=" ORDER BY title ASC";
  $result = mysqli_query($wpdb->dbh,$sql);
  $sno = 1;
  while($fetch = mysqli_fetch_array($result)){
   $title = $fetch['title'];
   $meaning = $fetch['meaning'];
   $description = $fetch['description'];
  ?>
  <tbody>
  <tr>
    <td><?php echo $sno; ?></td>
    <td><?php echo $title; ?></td>
    <td><?php echo $meaning; ?></td>
    <td><?php echo $description; ?></td>
  </tr>
</tbody>
      <?php
   $sno ++;
  } ?>
 </table>