<?php
    $db=mysql_connect($host, $username, $password) or die('Could not connect');
    mysql_select_db($db_name, $db) or die('');

    $res = mysql_query("데모작성시 요청했던 쿼리") or die('Could not query');
    $json = array();

    if(mysql_num_rows($res)){
        $i=0;
        $row=mysql_fetch_assoc($res);
        while($row=mysql_fetch_row($res)){
                $i++;   
                $json['pinfo'][$i]=array(
                      'PNM' => $row['상품이름 컬럼명'],
                      'PID' => $row['상품코드 컬럼명'],
                      'CATNM' => $row['카테고리이름 컬럼명'],
                      'CATCD' => $row['카테고리코드 컬럼명'],
                      'PRC' => $row['가격 컬럼명'],
                      'PIMG' => $row['이미지경로 컬럼명']
                  );
        }
    }
    mysql_close($db);
    echo json_encode($json);
?>

euckr 일경우

                $json['pinfo'][$i]=array(
                      'PNM' => urlencode($row['상품이름 컬럼명']),
                      'PID' => $row['상품코드 컬럼명'],
                      'CATNM' => $row['카테고리이름 컬럼명'],
                      'CATCD' => $row['카테고리코드 컬럼명'],
                      'PRC' => $row['가격 컬럼명'],
                      'PIMG' => $row['이미지경로 컬럼명']
                  );

$output = json_encode($json);
echo urldecode($output);

php, ajax, json 샘플