Codeigniter Data Table Server Side

function contentData(){ // datatables processing
		
		/* Array of database columns which should be read and sent back to DataTables. Use a space where
         * you want to insert a non-database field (for example a counter or static image)
         */
		$aColumns = array("'no'","data_tabel.id_konten","data_tabel.nama_kat","data_tabel.nama_konten","data_tabel.status_posting","'option'" );
       	 /* Indexed column (used for fast and accurate table cardinality) */
        $sIndexColumn = "data_tabel.id_konten";
        /* DB table to use */
        $aTable = array( "(SELECT a.id_konten, a.nama_konten, b.nama_kat, a.status_posting FROM tb_konten a
        					INNER JOIN tb_konten_kat b ON a.id_kat = b.id_kat 
        					ORDER BY a.id_konten ASC 
        				  ) AS data_tabel"
        				);

        /* DB join field */
        $aJoin = array( );

    
        $iDisplayStart = $this->input->get_post('iDisplayStart', true);
        $iDisplayLength = $this->input->get_post('iDisplayLength', true);
        $iSortCol_0 = $this->input->get_post('iSortCol_0', true);
        $iSortingCols = $this->input->get_post('iSortingCols', true);
        $sSearch = $this->input->get_post('sSearch', true);
        $sEcho = $this->input->get_post('sEcho', true);
    
        // Paging
        if(isset($iDisplayStart) && $iDisplayLength != '-1')
        {
            $this->DB_SSO->limit($iDisplayLength,$iDisplayStart);
        }
        
        // Ordering
        if(isset($iSortCol_0))
        {
            for($i=0; $i<intval($iSortingCols); $i++)
            {
                $iSortCol = $this->input->get_post('iSortCol_'.$i, true);
                $bSortable = $this->input->get_post('bSortable_'.intval($iSortCol), true);
                $sSortDir = $this->input->get_post('sSortDir_'.$i, true);
    
                if($bSortable == 'true')
                {
                    $this->DB_SSO->order_by($aColumns[intval($this->DB_SSO->escape_str($iSortCol))], $this->DB_SSO->escape_str($sSortDir));
                }
            }
        }

        /* 
         * Table
         */
		$sTable = implode(', ',$aTable);

        
        /* 
         * Join
         */
		if(count($aJoin) > 0) $sJoin = "WHERE ".implode(' AND ',$aJoin);
		else $sJoin = "";

        /* 
         * Filtering
         * NOTE this does not match the built-in DataTables filtering which does it
         * word by word on any field. It's possible to do here, but concerned about efficiency
         * on very large tables, and MySQL's regex functionality is very limited
         */
        if(isset($sSearch) && !empty($sSearch))
        {
            for($i=0; $i<count($aColumns); $i++)
            {
                $bSearchable = $this->input->get_post('bSearchable_'.$i, true);
                
                // Individual column filtering
                if(isset($bSearchable) && $bSearchable == 'true')
                {
                    $this->DB_SSO->or_like($aColumns[$i], $this->DB_SSO->escape_like_str($sSearch));
                }
            }
        }
        
        // Select Data
        $this->DB_SSO->select('SQL_CALC_FOUND_ROWS '.str_replace(' , ', ' ', implode(', ', $aColumns)), false);
        $rResult = $this->DB_SSO->get($sTable);
    
        // Data set length after filtering
        $this->DB_SSO->select('FOUND_ROWS() AS found_rows');
        $iFilteredTotal = $this->DB_SSO->get()->row()->found_rows;
    
        // Total data set length
        $queryResult = $this->DB_SSO->query("SELECT COUNT(".$sIndexColumn.") as tot
									            FROM $sTable
												$sJoin");
        $dataResult = $queryResult->row_array();
        $iTotal = $dataResult['tot'];
        //$iTotal = $this->DB_SSO->count_all($sTable);
    
        // Output
        $output = array(
            'sEcho' => intval($sEcho),
            'iTotalRecords' => $iTotal,
            'iTotalDisplayRecords' => $iFilteredTotal,
            'aaData' => array()
        );
        
        $no = intval($this->DB_SSO->escape_str( $this->input->get('iDisplayStart') ));
        foreach($rResult->result_array() as $aRow)
        {
        	$no++;
            $row = array();
            
         	for ( $i=0 ; $i<count($aColumns) ; $i++ ){
            	if($aColumns[$i] == "'option'" ){
            		$colName = explode('.',$sIndexColumn);
            		$id = base64_encode($aRow[ $colName[1] ]);
					$row[] = 	"<div align='center'>
								<a class='input-frm' title='Edit' href='content_c/contentSubFrm?act=upd&id=".$id."' onmouseover=\"$(this).tooltip('show')\" data-toggle='tooltip' data-placement='top'><i class='icon-edit'></i></a>
                           		<a class='input-frm delete-data cur-point' data-redir='content_c/ContentCat' data-url='content_c/contentSubAction?act=del&id=".$id."' title='Delete' onmouseover=\"$(this).tooltip('show')\" data-toggle='tooltip' data-placement='top'><i class='icon-trash'></i></a>
								</div>";
            	}else if( $aColumns[$i] == "'no'" ){
            		 /* No output */
                    $row[] = "<div align='center'>".$no."</div>";
            	}else{
            		/* General output */
					$colName = explode('.',$aColumns[$i]);
                    $row[] = $aRow[ $colName[1] ];
            	}
            }
    
            $output['aaData'][] = $row;
        }
    
        echo json_encode($output);
	}

thx @catur_satrya