programme_search.module

<?php

/**
 * Implements hook_menu().
 */
function programme_search_menu() {
  $items['programme_search/autocomplete'] = array(
    'page callback' => 'programme_search_autocomplete',
    'access arguments' => array('access content'),
    'type' => MENU_CALLBACK
  );
  return $items;
}

/**
 * Build a basic form. 
 */
function programme_search_search_form($form, &$form_state) {
  $form['search_programmes'] = array(
    '#title' => t(''),
    '#type' => 'textfield',
    '#default_value' => t('Start typing...'),
    '#autocomplete_path' => 'programme_search/autocomplete',
  );
   return $form;
}

/**
 * Menu callback function.
 *
 * @param string $string
 *  The string that will be searched.
 * @return object
 *  A JSON object.
 */
function programme_search_autocomplete($string) {

  $matches = array();

  $query = db_select('node', 'n');

  $query->join('field_data_field_programme_search_terms', 'st', 'st.entity_id = n.nid');
  $query->join('taxonomy_term_data', 'td', 'td.tid = st.field_programme_search_terms_tid');

  $or = db_or();
  $or->condition('n.title', '%' . db_like($string) . '%', 'LIKE');
  $or->condition('td.name', '%' . db_like($string) . '%', 'LIKE');

  $query->fields('n', array('nid', 'title'));
  $query->condition('n.type', 'programme', '=');
  $query->condition($or);
  $query->range(0, 20);

  $return = $query->execute();

  foreach ($return as $row) {
    $matches[drupal_get_path_alias('node/' . $row->nid)] = check_plain($row->title);
  }

  if (empty($matches)) {
    $matches['0'] = t('No matches.');
  }

  drupal_json_output($matches);
}