source: sipes/modules_contrib/services/auth/services_oauth/services_oauth.install

<?php
/**
 * @file
 * Install, update and uninstall functions for the services_oauth module.
 */

/**
 * Implementation of hook_install().
 */
function services_oauth_install() {
  drupal_install_schema('services_oauth');
}

/**
 * Implementation of hook_uninstall().
 */
function services_oauth_uninstall() {
  drupal_uninstall_schema('services_oauth');
}

/**
 * Implementation of hook_schema().
 */
function services_oauth_schema() {
  $schema = array();

  return $schema;
}

function services_oauth_update_6001() {
  $ret = array();

  // Rename the authentication and authorization settings variables
  $authentication = variable_get('services_oauth_authentication_levels', array());
  $authorization = variable_get('services_oauth_authorization_settings', array());
  variable_del('services_oauth_authentication_levels');
  variable_del('services_oauth_authorization_settings');
  variable_set('services_oauth_authentication_levels_', $authentication);
  variable_set('services_oauth_authorization_settings_', $authorization);

  return $ret;
}

function services_oauth_update_6200() {
  variable_del('services_oauth_authentication_levels_');
  variable_del('services_oauth_authorization_settings_');

  return array();
}