AJAX COUNTRY, STATE, CITY DROPDOWNLIST IS THE USE OF JSON CORRECT

AJAX COUNTRY, STATE, CITY DROPDOWNLIST IS THE USE OF JSON CORRECT

 CAN YOU TELL ME IF THIS IS CORRECT


?>
<SCRIPT>
    $(Document).ready(function(){
     var COUNTRYCOD = 0;
          $.ajax({
   type : "POST",
            url  : "GETCOUNTRIES.PHP",
            success : function(){
               var CBOCONTROL = $("#COUNTRYCBO");
      CBOCONTROL.empty();   
               for ( X = 0; X < COUNTRY.length;x++){
      CBOCONTROL.append("<OPTION VALUE=" + COUNTRY[X].COUNTRYCOD + ">" + COUNTRY[X].COUNTRYNAM + "</OPTION>");
  };
   };  
 });

    });
        $("#COUNTRYCBO").click ( function(){
    var COUNTRYCOD = COUNTRYCBO.val();
POSTEDDATA  = { "COUNTRYCOD" : COUNTRYCOD };
 
$.ajax({
       type    : "POST"
       url     : "GETSTATE.PHP",
       data    : { MYDATA: POSTEDDATA}
       dataType: "json", 
       success : function(STATES){
     var CBOCONTROL = $("#STATECBO");
     CBOCONTROL.empty();
     for ( N = 0; N < STATES.length; n++){
      CBOCONTROL.Append($("<OPTION></OPTION>").attr("value",STATES[N].STATECOD).text(STATES[N].STATENAM));
 };
};
});
   
      $("#STATECBO").click ( function(){
    $STATECOD = STATECBO.val();
POSTEDDATA  = {
                    "COUNTRYCOD" : COUNTRYCOD ,
                    "STATECOD"   : STATECOD 
  }  
$.ajax({
       type    : "POST",
       url     : "GETCITIES.PHP",
       data    : { MYDATA : POSTEDDATA };
       dataType: "json", 
       success : function(CITIES){
    var CBOCONTROL = $(#CITYCBO );
    CBOCONTROL.empty();
for ( N = 0; N < CITIES.length; N++ ){
             CBOCONTROL.Append($("<OPTION></OPTION>").attr("value",CITIES[N].CITYCOD).text(CITIES[N].CITYNAM));
        };
};
});
   
   
   
   </SCRIPT>
   
   <SELECT NAME="DDCOUNTRY" ID="COUNTRYCBO">
   
   
   </SELECT>
   
   <SELECT NAME="DDSTATE"   ID="STATECBO">
   
   
   </SELECT>
   <SELECT NAME="DDCITY"     ID="CITYCBO">
   
   
   
   </SELECT>
   

   
       (PHP)
   
    #######################################################
#######################################################
                GETCOUNTRIES.PHP
   
   <?php
   $CON        = mysql_connect("localhost","root","");
mysql_select_db ( "AJAXDBF", $CON );
    $SQLCOUNTRY = " SELECT * FROM COUNTRY ";
$FCOUNTRY   = mysql_query( $SQLCOUNTRY , $CON);
while ( $ROW  = mysql_fetch_array( $FCOUNTRY )){
   $COUNTRIES   = array(
 'COUNTRYCOD' => $ROW["COUNTRYCOD"],
     'COUNTRYNAM' => $ROW["COUNTRYNAM"]);  
}
    echo ( json_encode( $COUNTRIES ));

    ################################################################### 
###################################################################
           GETSTATE.PHP
    $DATA        = $_POST['MYDATA'];
    $DATADECODE  = json_decode( $DATA );
$COUNTRYCOD  = $DATADECODE["COUNTRYCOD"];
    $CON      = mysql_connect("localhost","root","");
mysql_select_db ( "AJAXDBF", $CON );
$SQLSTATE = " SELECT * FROM STATES WHERE COUNTRYCOD=" . $COUNTRYCOD
$FSTATE   = mysql_query (  $SQLSTATE, $CON );
while ( $ROW = mysql_fetch_array($FSTATE)){
      $STATES = array(
                'STATECOD' => $ROW["STATECOD"],
                'STATENAM' => $ROW["STATENAM"]);
                           
}
    echo(json_encode($STATES));
####################################################################
####################################################################
             GETCITIES.PHP        
 $DATA         =  $_POST['MYDATA'];
      $DATADECODE   =  json_decode( $DATA);
      $COUNTRYCOD   =  $DATADECODE["COUNTRYCOD"]; 
 $STATECOD     =  $DATADECODE["STATECOD"];  
 $CON          = mysql_connect("localhost", "root","");
 mysql_select_db( "AJAXDBF", $CON );
      $SQLCITY = " SELECT * FROM CITY WHERE COUNTRYCOD =" . $COUNTRYCOD ;
      $SQLCITY.= " WHERE   STATECOD =" . $STATECOD ;  
 $FCITY   =  mysql_query( $SQLCITY, $CON ) ;
      while ( $ROW  = mysql_fetch_array( $FCITY )){
      $CITIES = array( 
     'CITYCOD'=> $ROW["CITYCOD"],
 'CITYNAM'=> $ROW["CITYNAM"])
 }
 echo(json_encode($CITIES));