排序，分页，搜索jQuery数据表搜索端处理不起作用

我正在使用PHP jQuery数据服务器处理代码并能够在表中列出数据（通过JSON），但排序，分页和搜索不起作用 . 它在加载时加载表中的所有数据，并且对于排序列，使用任何数据和分页编号进行搜索，请求/响应相同 .

客户端：

$(".machines-data").dataTable({

                aLengthMenu: [ [5, 10, 25, 50, 100, 150, "-1"], [5, 10, 25, 50, 100, 150, "All"] ],
                iDisplayLength: 5,
                searching: true,
                "aaSorting": [],
                columnDefs: [ { orderable: true } ],
                "bServerSide": true,
                "processing": true,
                "serverSide": true,

                "ajax": { "url": "/machines/server.php", "type": "POST", "dataType": "json", "cache": false },

                    "aoColumnDefs": [
            { "data": "id" },
            { "data": "ip" },
            { "data": "machine" },
            { "data": "status" }
        ]

            });

JSON响应：

{"sEcho":0,"iTotalRecords":"45","iTotalDisplayRecords":"45","aaData":[["1","xx.yy.xx.yy","machine1","Completed"],[["1","xx.yy.xx.yy","machine2","Completed"]] .. 45 rows}

服务器端：

<?php

ignore_user_abort(true);

if($_POST) {

    $aColumns = array( 'id', 'ip', 'machine','status' );

    $sIndexColumn = "id";

    $sTable = "1_machines";

    $gaSql['user']       = "root";
    $gaSql['password']   = "pwd";
    $gaSql['db']         = "machines";
    $gaSql['server']     = "localhost";

    function fatal_error ( $sErrorMessage = '' )
    {
        header( $_SERVER['SERVER_PROTOCOL'] .' 500 Internal Server Error' );
        die( $sErrorMessage );
    }

    if ( ! $gaSql['link'] = mysql_pconnect( $gaSql['server'], $gaSql['user'], $gaSql['password']  ) )
    {
        fatal_error( 'Could not open connection to server' );
    }

    if ( ! mysql_select_db( $gaSql['db'], $gaSql['link'] ) )
    {
        fatal_error( 'Could not select database ' );
    }

    $sLimit = "";
    if ( isset( $_GET['iDisplayStart'] ) && $_GET['iDisplayLength'] != '-1' )
    {
        $sLimit = "LIMIT ".intval( $_GET['iDisplayStart'] ).", ".
            intval( $_GET['iDisplayLength'] );
    }

    $sOrder = "";
    if ( isset( $_GET['iSortCol_0'] ) )
    {
        $sOrder = "ORDER BY  ";
        for ( $i=0 ; $i<intval( $_GET['iSortingCols'] ) ; $i++ )
        {
            if ( $_GET[ 'bSortable_'.intval($_GET['iSortCol_'.$i]) ] == "true" )
            {
                $sOrder .= "`".$aColumns[ intval( $_GET['iSortCol_'.$i] ) ]."` ".
                    ($_GET['sSortDir_'.$i]==='asc' ? 'asc' : 'desc') .", ";
            }
        }

        $sOrder = substr_replace( $sOrder, "", -2 );
        if ( $sOrder == "ORDER BY" )
        {
            $sOrder = "";
        }
    }

    $sWhere = "";
    if ( isset($_GET['sSearch']) && $_GET['sSearch'] != "" )
    {
        $sWhere = "WHERE (";
        for ( $i=0 ; $i<count($aColumns) ; $i++ )
        {
            $sWhere .= "`".$aColumns[$i]."` LIKE '%".mysql_real_escape_string( $_GET['sSearch'] )."%' OR ";
        }
        $sWhere = substr_replace( $sWhere, "", -3 );
        $sWhere .= ')';
    }

    for ( $i=0 ; $i<count($aColumns) ; $i++ )
    {
        if ( isset($_GET['bSearchable_'.$i]) && $_GET['bSearchable_'.$i] == "true" && $_GET['sSearch_'.$i] != '' )
        {
            if ( $sWhere == "" )
            {
                $sWhere = "WHERE ";
            }
            else
            {
                $sWhere .= " AND ";
            }
            $sWhere .= "`".$aColumns[$i]."` LIKE '%".mysql_real_escape_string($_GET['sSearch_'.$i])."%' ";
        }
    }


    $sQuery = "
        SELECT SQL_CALC_FOUND_ROWS `".str_replace(" , ", " ", implode("`, `", $aColumns))."`
        FROM   $sTable
        $sWhere
        $sOrder
        $sLimit
        ";
    $rResult = mysql_query( $sQuery, $gaSql['link'] ) or fatal_error( 'MySQL Error: ' . mysql_errno() );

    $sQuery = "
        SELECT FOUND_ROWS()
    ";
    $rResultFilterTotal = mysql_query( $sQuery, $gaSql['link'] ) or fatal_error( 'MySQL Error: ' . mysql_errno() );
    $aResultFilterTotal = mysql_fetch_array($rResultFilterTotal);
    $iFilteredTotal = $aResultFilterTotal[0];

    $sQuery = "
        SELECT COUNT(`".$sIndexColumn."`)
        FROM   $sTable
    ";
    $rResultTotal = mysql_query( $sQuery, $gaSql['link'] ) or fatal_error( 'MySQL Error: ' . mysql_errno() );
    $aResultTotal = mysql_fetch_array($rResultTotal);
    $iTotal = $aResultTotal[0];

    $output = array(
        "sEcho" => intval($_GET['sEcho']),
        "iTotalRecords" => $iTotal,
        "iTotalDisplayRecords" => $iFilteredTotal,
        "aaData" => array()
    );

    while ( $aRow = mysql_fetch_array( $rResult ) )
    {
        $row = array();
        for ( $i=0 ; $i<count($aColumns) ; $i++ )
        {
            if ( $aColumns[$i] == "started_on" )
            {
                $row[] = ($aRow[ $aColumns[$i] ]=="0") ? ' - ' : $aRow[ $aColumns[$i] ];
            }
            else if ( $aColumns[$i] != ' ' )
            {
                /* General output */
                $row[] = $aRow[ $aColumns[$i] ];
            }
        }
        $output['aaData'][] = $row;
    }

    echo json_encode( $output );

    exit (0);

}

?>