Example of building a table with rows from a db table in Drupal

dbselect2themetable.php

<?php

/**
 * Menu callback.
 */
function this_is_a_menu_callback() {
  $header = array('nid' => 'ID', 'title' => 'Title');

  $query = db_select('node', 'n', array('fetch' => PDO::FETCH_ASSOC))
    ->fields('n', array('nid', 'title'))
    ->extend('PagerDefault')
    ->limit(10)
    ->extend('TableSort')
    ->orderByHeader($header);

  $rows =$query
    ->execute()
    ->fetchAllAssoc('nid');

  $build = array();
  $build['nodes'] = array(
    '#theme' => 'table',
    '#header' => $header,
    '#rows' => $rows,
    '#empty' => t('No nodes available.'),
  );
  $build['pager'] = array(
    '#theme' => 'pager',
  );

  //print render($build);
  
  return $build;
}