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Hi Vitaly, Yep... gorfs.nodes is a view. And the schema is: gorfs.inode_segments So... CREATE INDEX index_name ON gorfs.inode_segments(st_ctime) Is that correct? It would be "st_ctime"? I've rewriten the query as well. Thank you for that! Thank you Lucas > Date: Sun, 10 Jan 2016 21:23:01 -0800 > Subject: Re: Slow Query - PostgreSQL 9.2 > From: vitaly.burovoy@xxxxxxxxx > To: smerlo50@xxxxxxxxxxx > CC: pgsql-general@xxxxxxxxxxxxxx > > On 1/10/16, Vitaly Burovoy <vitaly.burovoy@xxxxxxxxx> wrote: > > On 1/10/16, Saulo Merlo <smerlo50@xxxxxxxxxxx> wrote: > >> I've got a slow query.. I'd like to make it faster.. Make add an index? > >> Query: > >> SELECT > >> <<overquoting>> > >> FROM gorfs.nodes AS f > >> <<overquoting>> > >> WHERE f.file_data IS NOT NULL > >> AND ((transaction_timestamp() AT TIME ZONE 'UTC') > (f.last_changed + > >> '24 > >> months' :: INTERVAL)) LIMIT 100; > > > >> <<overquoting>> > >> "Total runtime: 94989.208 ms"What could I do to make it faster? Thank > >> you. > > > > At least you can add an index: > > CREATE INDEX ON gorfs.nodes(last_changed) > > > > and rewrite part of WHERE clause to: > > (f.last_changed < (transaction_timestamp() AT TIME ZONE 'UTC' - '24 > > months'::INTERVAL)) > > > > It allows to decrease the slowest part of your query (sequence > > scanning of a table, all 13.5M rows): > >> -> Seq Scan on "inodes" "t" (cost=0.00..1411147.24 rows=13416537 > >> width=29) (actual time=94987.224..94987.224 rows=0 loops=1) > >> Filter: ("timezone"('UTC'::"text", "transaction_timestamp"()) > > >> (("st_ctime")::timestamp without time zone + '2 years'::interval)) > > > > compare that time to the one in the topmost row of EXPLAIN: > >> Limit (cost=1556.99..1336437.30 rows=100 width=186) (actual > >> time=94987.261..94987.261 rows=0 loops=1) > > Hmm. It seems that gorfs.nodes is a view. > So creating index should be something like (I have no idea that schema > name for it): > CREATE INDEX ON _schema_name_.inodes(st_ctime) > > -- > Best regards, > Vitaly Burovoy > > > -- > Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) > To make changes to your subscription: > http://www.postgresql.org/mailpref/pgsql-general |
