/**
  * Drop all missing or modified views
  *
  * @param $ofs         output file segmenter
  * @param $old_schema  original schema
  * @param $new_schema  new schema
  */
 public static function drop_views($ofs, $old_schema, $new_schema)
 {
     if ($old_schema != NULL) {
         foreach (dbx::get_views($old_schema) as $old_view) {
             $new_view = dbx::get_view($new_schema, $old_view['name']);
             if ($new_view == NULL || self::is_view_modified($old_view, $new_view)) {
                 $ofs->write(mssql10_view::get_drop_sql($old_schema, $old_view) . "\n");
             }
         }
     }
 }