SELECT DISTINCT ON (id) id, description
FROM list_index li
ORDER BY id, rpt_key DESC;

##</code><code>##

SELECT DISTINCT id,
	(SELECT description from list_index li_i
	 WHERE li_i.id = li_o.id
	 ORDER BY created_at DESC limit 1) AS description
	FROM list_index li_o;

##</code><code>##

SELECT id,
	(SELECT description from list_index li_i
	 WHERE li_i.id = li_o.id
	 ORDER BY created_at DESC limit 1) AS description
	FROM
		(SELECT DISTINCT id FROM list_index) li_o;