<?php
$id1=$_GET['id1'];
$id2=$_GET['id2'];
$level=$_GET['l'];

if($level==1) // Get level 1 data
    $sql="select distinct id1 as id from cascading order by id1";
else 
    $sql="select distinct id2 as id from cascading where id1=$id1 order by id2";
  
$cn=mysql_connect('localhost', 'root', '123456');
mysql_selectdb('rsywx');
$res=mysql_query($sql);
$arr=array();
while($row=mysql_fetch_object($res))
{
    array_push($arr, $row->id);
}

$j_ret=json_encode($arr);

echo $j_ret;

/*$ret=$id1.' '.$id2.' '.$level;
$j_ret=json_encode($ret);

echo $j_ret;*/


?>