I'm getting sequential scans (and poor performance), on scans using my
primary keys. This is an older postgres.
Can anyone help figure out why?
demo=# \d xx_thing Table "public.xx_thing" Column | Type |
Modifiers
-------------------------+-----------------------------+-----------thing_id | bigint
|not null
thing_model | character varying(128) |thing_color | character varying(128) |thing_year
| integer |
Indexes: "xx_thing_pkey" primary key, btree (thing_id)
demo=# analyze verbose xx_thing_event;
INFO: analyzing "public.xx_thing_event"
INFO: "xx_thing_event": 3374 pages, 3000 rows sampled, 197478 estimated
total rows
demo=# explain update xx_thing_event set thing_color='foo' where
thing_event_id=10000; QUERY PLAN
---------------------------------------------------------------------Seq Scan on xx_thing_event (cost=0.00..5842.48
rows=1width=110) Filter: (thing_event_id = 10000)
(2 rows)
demo=# select * from version(); version
----------------------------------------------------------------------------------------------------------PostgreSQL
7.4.1on i686-pc-linux-gnu, compiled by GCC gcc (GCC) 3.2.3
20030502 (Red Hat Linux 3.2.3-20)
(1 row)