Find duplicate records in php mysql

To find duplicate records in php mysql database use this query. It will list all duplicate entries which occurs more than once.

  $table='emails';
  
  $sql="SELECT email FROM $table WHERE email in (
        SELECT email FROM $table GROUP BY email 
        HAVING count(email) > 1)";
  $result=mysql_query($sql);
  $n=1;
  while($row = mysql_fetch_array($result)){
      echo '<br />('.$n.')';
      echo $row['email'];
      $n++;
  }