Sorting problem

[Roberto]

Hi,

i create this to get grid info from mysql database:

<div id="grid"></div>

 <script>

             

                 

                $(document).ready(function() {

                    $("#grid").kendoGrid({

                        dataSource: {

                                                 

                            transport: {

                                read: {

                                    url: "page.php",

                                    type: "post",

                                    dataType: "json"

                                }

                            },

                            schema: {

                                 

                                data: "data",

                                total: "pageSize"

                                 

                            },

                            pageSize: 200,

                            serverPaging: true,

                    serverSorting: true

                        },

                        

                         

                         

                        height: 450,

                        scrollable: true,

                        groupable: true,

                        sortable: true,

                        filterable: true,

                        pageable: true,

            selectable: "multiple row",

                         

                        columns: [

                            {

                                field: "sel",

                                template: "<input type=\'checkbox\' id=\'select\' name=\'sel\' value=#=ARTICLE_ID#  />",

                                filterable: false,

                                sortable: false,

                                groupable: false,

                                width: 50

                            },

                            "CODE",

                            

                            {

                                field: "CATEGORY_NAME",

                                title: "CATEGORY"

                                 

                            }

                            ,

                            "ARTICLE_NAME",

                                 

                            {

                                field: "edit",

                                template: "<a class=\'link_page\' href=\'/gestionale/factory/article/edit/id/#=ARTICLE_ID#\'>Edit</a>",

                                filterable: false,

                                sortable: false,

                                groupable: false,

                                width: 50

                            },

                        ]

                    });

                });

            </script>

my page.php

i do a query with an inner join

select a.NAME as ARTICLE_NAME,a.CODE,c.NAME as CATEGORY_NAME from T_ARTICLE as a inner join T_CATEGORY as c on a.CATEGORY_ID = c.ID

i do serverSorting because the table have more rows (300.000). When i click on TH CATEGORY_NAME the script run a ajax call to page.php and passes through POST the sort array  with the FIELD CATEGORY_NAME, but the query is wrong because in ORDER clause i don't insert CATEGORY_NAME, i would insert c.NAME. 
Is it possible to define the name of the fields that i will use in the sort and filter?

Thanks