Drupal 7: Update pathauto aliases

gistfile1.php

<?php
/*
 * Use in devel/php or with drush scr.
 * Compatible with http://drupal.org/project/redirect module.
 */
// Some query.
$result = db_select('node', 'n')
  ->fields('n', array('nid'))
  ->condition('n.type', 'article')
  ->condition('n.status', 1)
  ->range(0, 300)
  ->orderBy('n.nid')
  ->execute();

foreach ($result as $obj) {
  $node = node_load($obj->nid);
  $node->path = array('pathauto' => TRUE);
  pathauto_node_update_alias($node, 'update');
  // Or pathauto_taxonomy_term_update_alias() for terms.
}