district of columbia

I am developing this form module to delete only fid and uid from mydata table in the database but i cont get it to work. Please help....

<?php

function mydata_page_form($form, $form_state){

$form = array();

$header = array( t('File ID'), t('File Name'), t('File link'), t('User'),
);

$query = db_select('mydata', 'm')->extend('PagerDefault') ;
$query->join('file_managed', 'f', 'f.fid = m.fid ');
$query->addjoin('INNER','users', 'u', 'm.uid = u.uid ');
$query
->fields ('m', array('fid', 'uid'))
->fields ('f', array('filename', 'uri'))