PHP code to create CSV file from MySQL table

Hi All,
Use this code..
For this program to run create database SNITDB  and create a table tweet(tid,sname,tweet)
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<?php
$con=mysql_connect("localhost","root","");
mysql_select_db("SNITDB",$con);
header('Content-Type: text/csv; charset=utf-8');
      header('Content-Disposition: attachment; filename=da.csv');
       $output = fopen("php://output", "w");
    fputcsv($output, array('tid','sname', 'tweet'));
        $query = "select distinct * from tweet where label=0";
        $result = mysql_query($query, $con);
        while($row = mysql_fetch_array($result))
        {
             fputcsv($output,array($row['tid'],$row['sname'],$row['tweet']));
             $sql="update tweet set label=1 where tid='$row[tid]'";
             mysql_query($sql, $con);
        }
      fclose($output);

?>