Hi, I have the following query - is there anything i've missed or is it
just slow?!
I have an index on meta.date that i thought might have been used but
isn't (I know it would only be a small performance increase in the
current plan).
meta.date is between 1999 and 2003. I think generally the most
efficient order to do things would be to extract all the messages
within the date range and then search over just them.
I am currently in the process of setting up full text indexing as
described in the techdocs.postgresql.org i guess this is the main way
of speeding up searches through ~40GB of bulk text?
Thanks!...
m
EXPLAIN ANALYZE SELECT meta.msg_id, date, from_line, subject FROM
message ,meta WHERE meta.date >= '15-06-2003 00:00:00' AND meta.date <=
'26-06-2003 00:00:00' AND message.header||message.body ILIKE '%chicken%'
AND meta.sys_id = message.sys_id ORDER BY meta.date DESC;
QUERY PLAN
------------------------------------------------------------------------
------------------------------------------------------------------------
------
Sort (cost=50.16..50.17 rows=1 width=120) (actual time=412333.65..
412333.76 rows=166 loops=1)
Sort Key: meta.date
-> Nested Loop (cost=0.00..50.15 rows=1 width=120) (actual time=
400713.41..412332.53 rows=166 loops=1)
-> Seq Scan on message (cost=0.00..25.00 rows=5 width=8) (actual time=
58.18..410588.49 rows=20839 loops=1)
Filter: ((header || body) ~~* '%chicken%'::text)
-> Index Scan using meta_pkey on meta (cost=0.00..5.02 rows=1 width=
112) (actual time=0.07..0.07 rows=0 loops=20839)
Index Cond: (meta.sys_id = "outer".sys_id)
Filter: ((date >= '2003-06-15 00:00:00'::timestamp without time zone)
AND (date <= '2003-06-26 00:00:00'::timestamp without time zone))
Total runtime: 412334.08 msec
(9 rows)