functions.py 文件源码

def columns(self):
        """The set of columns exported by this :class:`.FunctionElement`.

        Function objects currently have no result column names built in;
        this method returns a single-element column collection with
        an anonymously named column.

        An interim approach to providing named columns for a function
        as a FROM clause is to build a :func:`.select` with the
        desired columns::

            from sqlalchemy.sql import column

            stmt = select([column('x'), column('y')]).\
                select_from(func.myfunction())


        """
        return ColumnCollection(self.label(None))