code: public boolean isList4Select(final String _selectStmt)
          throws EFapsException
      {
          final OneSelect oneselect = this.selectStmt2OneSelect.get(_selectStmt);
          return oneselect == null ? false : oneselect.isMultiple();
      }
docs: Method to determine it the select statement returns more than one value.
  
  @param _selectStmt selectstatement the attribute is wanted for
  @return true it the oneselect is muliple, else false
  @throws EFapsException on error