On 20/07/2012 22:33, Claudio Freire wrote:
> On Fri, Jul 20, 2012 at 6:27 PM, Ioannis Anagnostopoulos
> <ioannis(at)anatec(dot)com> wrote:
>> On 20/07/2012 22:23, Claudio Freire wrote:
>>> On Fri, Jul 20, 2012 at 6:19 PM, Ioannis Anagnostopoulos
>>> <ioannis(at)anatec(dot)com> wrote:
>>>> " -> Nested Loop (cost=0.00..20942.93 rows=53 width=144) (actual
>>>> time=62.174..17783236.718 rows=387105 loops=1)"
>>>> " Join Filter: (feed_all_y2012m07.message_copies.msg_id =
>>>> feed_all_y2012m07.ship_pos_messages.msg_id)"
>>>> " -> Append (cost=0.00..19057.93 rows=53 width=33) (actual
>>>> time=62.124..5486473.545 rows=387524 loops=1)"
>>> Misestimated row counts... did you try running an analyze, or upping
>>> statistic targets?
>> I have run analyse every so often. I think the problem is that as I get 16K
>> new rows every minutes, the "stats" are always out... Possible?
>
> Looking at this:
>
> " -> Index Scan using
> idx_message_copies_wk2_date_src_pos_partial on message_copies_wk2
> message_copies (cost=0.00..19057.93 rows=52 width=32) (actual
> time=62.124..5486270.845 rows=387524 loops=1)"
> " Index Cond: ((date_trunc('day'::text,
> msg_date_rec) = '2012-07-17 00:00:00'::timestamp without time zone)
> AND (src_id = 1))"
> " Filter: ((date_part('day'::text,
> msg_date_rec) = 17::double precision) AND (NOT (((((pos_georef1)::text
> || (pos_georef2)::text) || (pos_georef3)::text) ||
> (pos_georef4)::text) IS NULL)) AND (((((pos_georef1)::text ||
> (pos_georef2)::text) || (pos_georef3)::text) || (pos_georef4)::text)
> <> ''::text))"
>
> It's very possible.
>
> I think pg 9.1 had a fix for that, but I'm not sure it will help in
> your case, I'd have to know what that index looks like.
Here is the index:
CREATE INDEX idx_message_copies_wk2_date_src_pos_partial
ON feed_all_y2012m07.message_copies_wk2
USING btree
(date_trunc('day'::text, msg_date_rec), src_id, (((pos_georef1::text
|| pos_georef2::text) || pos_georef3::text) || pos_georef4::text))
TABLESPACE archive
WHERE (((pos_georef1::text || pos_georef2::text) ||
pos_georef3::text) || pos_georef4::text) IS NOT NULL OR NOT
(((pos_georef1::text || pos_georef2::text) || pos_georef3::text) ||
pos_georef4::text) = ''::text;