Issue #3190539 by douggreen, Anybody: Duplicate names not filtered properly with distinct

      $query = \Drupal::database()->select($field_table, 'f');

      $query->fields('f', ['entity_id', $field_column]);

      $query->condition($field_column, $query->escapeLike($typed_string) . '%', 'LIKE');

      $query->distinct(TRUE);

      $results = $query->execute()->fetchAllKeyed();

      foreach ($results as $id => $value) {

        $entity = $entity_type_manager->getStorage($entity_type_id)->load($id);

        if ($entity->access('edit')) {

          $existing_values[] = [

          $existing_values[$value] = [

            'value' => $value,

            'label' => $value,

          ];

      }

    }

    return new JsonResponse($existing_values);

    return new JsonResponse(array_values($existing_values));

  }

}