code: protected Collection<String> getOldTablesDroppingScripts()
     {
        List<String> scripts = new ArrayList<String>();
  
        scripts.add("DROP TABLE " + valueTableName + "_OLD");
        scripts.add("DROP TABLE " + refTableName + "_OLD");
        scripts.add("DROP TABLE " + itemTableName + "_OLD");
  
        return scripts;
     }
docs: Returns SQL scripts for dropping existed old JCR tables.