How to represent dates BC

[jwp]

On Tuesday, July 24, 2012 2:55:29 AM UTC-7, Laszlo Nagy wrote:
>  >>> conn.getqueryvalue("select '1311-03-14 BC'::date")
> What is the good representation here? Should I implement my own date 

Do your datetime formatting in postgres: "select '1311-03-14 BC'::date::text"

PG does have a have a reasonable set of functions for working with datetime.
If you need something more complicated than a simple cast to text, I'd suggest creating a function:

CREATE OR REPLACE FUNCTION fmt_my_dates(date) RETURNS text LANGUAGE SQL AS
$$
SELECT EXTRACT(.. FROM $1)::text || ...
$$;