Displays information about a specified function; either external
    or stored. When you enter the SHOW FUNCTIONS statement without
    any arguments, SQL displays the name of the function only. The
    following table lists the information that you can display using
    a set of keywords with the SHOW FUNCTIONS statement:

    You
    Specify
    This:       SQL Displays Information About:

    COMMENT     The description of the function. If none exists,
                nothing displays.
    ID          The unique identification assigned to the function.
    LANGUAGE    The host language in which the function is coded.
    MODULE      The name of the module in which the function is
                defined.
    OWNER       The owner of the function.
    PARAMETER   Information about the parameters, including the
                number of arguments, the data type, return type,
                and how the parameter is passed.
    SOURCE      Displays the source definitions for the specified
                functions.