Access a Field / Column of a resultset by Number

hy group,

i currently look for a solution to access a resultset in a db-stored
function by number. in plpgsql thats not possible.
so i checked out plpython. so far so good, thats working:

CREATE OR REPLACE FUNCTION dokv_dorecnokeywords(sqlstatement VARCHAR)
RETURNS VOID AS
$$
  rv = plpy.execute(sqlstatement, 1)
  |||||->"SELECT * FROM art WHERE ak_nr='TEST'"
  s  = 'ak_bez'  |||| fieldname is static here, should be by number
  plpy.notice(s+'='+rv[0][s])
  return
$$ LANGUAGE plpythonu;

now i need a solution to get the number of fields as well as the
fieldnames of that resultset and run through all fields (by number or by
name). (i need the fieldname too)

--

Daniel Schuchardt
/Softwareentwicklung/

/http://www.prodat-sql.de/