Isso pode ser feito usando dblink. Eu mostrei um exemplo com uma inserção sendo confirmada, você precisará adicionar sua lógica de loop while e confirmar cada loop. Você pode http://www.postgresql.org/docs/9.3/static/contrib-dblink-connect.html
CREATE OR REPLACE FUNCTION log_the_dancing(ip_dance_entry text)
RETURNS INT AS
$BODY$
DECLARE
BEGIN
PERFORM dblink_connect('dblink_trans','dbname=sandbox port=5433 user=postgres');
PERFORM dblink('dblink_trans','INSERT INTO dance_log(dance_entry) SELECT ' || '''' || ip_dance_entry || '''');
PERFORM dblink('dblink_trans','COMMIT;');
PERFORM dblink_disconnect('dblink_trans');
RETURN 0;
END;
$BODY$
LANGUAGE plpgsql VOLATILE
COST 100;
ALTER FUNCTION log_the_dancing(ip_dance_entry text)
OWNER TO postgres;
BEGIN TRANSACTION;
select log_the_dancing('The Flamingo');
select log_the_dancing('Break Dance');
select log_the_dancing('Cha Cha');
ROLLBACK TRANSACTION;
--Show records committed even though we rolled back outer transaction
select *
from dance_log;