function menu_update_1006

Clean up duplicate system menu item entries.

Related topics

File

core/modules/menu/menu.install, line 141

Install, update and uninstall functions for the menu module.

Code

function menu_update_1006() {
  // With MIN() we make sure, we get the lowest mlid, which is the valid one of
  // duplicates.
  $query = 'SELECT MIN(mlid) as min_mlid, link_path, menu_name, plid, depth FROM {menu_links}';
  // Paths appearing more than once, limited to "system" entries.
  $query .= " WHERE module = 'system' GROUP BY link_path, menu_name, plid, depth HAVING count(link_path) > 1";
  $candidates = db_query($query)->fetchAllAssoc('link_path');

  // Sites updating from versions before 1.21.0 won't have duplicates.
  if (!empty($candidates)) {
    foreach ($candidates as $path => $values) {
      // Additionally to "link_path" and "module" columns, we compare more
      // values to make sure, we really only delete duplicates, not valid
      // records. We only delete items with an id higher than the lowest one
      // from the previous query.
      db_delete('menu_links')
        ->condition('link_path', $path)
        ->condition('module', 'system')
        ->condition('menu_name', $values->menu_name)
        ->condition('plid', $values->plid)
        ->condition('depth', $values->depth)
        ->condition('mlid', $values->min_mlid, '>')
        ->execute();
    }
  }
}