On Tue, 25 Jun 2019 at 05:31, Justin Pryzby <pryzby@xxxxxxxxxxxxx> wrote: > ts=# explain SELECT * FROM eric_enodeb_cell_metrics WHERE start_time BETWEEN '2019-01-01 04:00' AND '2019-01-01 05:00' OR start_time BETWEEN '2019-01-02 04:00' AND '2019-01-02 05:00'; > Append (cost=36.04..39668.56 rows=12817 width=2730) > -> Bitmap Heap Scan on eric_enodeb_cell_20190101 (cost=36.04..19504.14 rows=6398 width=2730) > Recheck Cond: (((start_time >= '2019-01-01 04:00:00-05'::timestamp with time zone) AND (start_time <= '2019-01-01 05:00:00-05'::timestamp with time zone)) OR ((start_time >= '2019-01-02 04:00:00-05'::timestamp with time zone) AND (start_time <= '2019-01-02 05:00:00-05'::timestamp with time zone))) > -> BitmapOr (cost=36.04..36.04 rows=6723 width=0) > -> Bitmap Index Scan on eric_enodeb_cell_20190101_idx (cost=0.00..16.81 rows=6465 width=0) > Index Cond: ((start_time >= '2019-01-01 04:00:00-05'::timestamp with time zone) AND (start_time <= '2019-01-01 05:00:00-05'::timestamp with time zone)) > -> Bitmap Index Scan on eric_enodeb_cell_20190101_idx (cost=0.00..16.03 rows=259 width=0) > Index Cond: ((start_time >= '2019-01-02 04:00:00-05'::timestamp with time zone) AND (start_time <= '2019-01-02 05:00:00-05'::timestamp with time zone)) > -> Bitmap Heap Scan on eric_enodeb_cell_20190102 (cost=36.08..20100.34 rows=6419 width=2730) > Recheck Cond: (((start_time >= '2019-01-01 04:00:00-05'::timestamp with time zone) AND (start_time <= '2019-01-01 05:00:00-05'::timestamp with time zone)) OR ((start_time >= '2019-01-02 04:00:00-05'::timestamp with time zone) AND (start_time <= '2019-01-02 05:00:00-05'::timestamp with time zone))) > -> BitmapOr (cost=36.08..36.08 rows=6982 width=0) > -> Bitmap Index Scan on eric_enodeb_cell_20190102_idx (cost=0.00..16.03 rows=259 width=0) > Index Cond: ((start_time >= '2019-01-01 04:00:00-05'::timestamp with time zone) AND (start_time <= '2019-01-01 05:00:00-05'::timestamp with time zone)) > -> Bitmap Index Scan on eric_enodeb_cell_20190102_idx (cost=0.00..16.84 rows=6723 width=0) > Index Cond: ((start_time >= '2019-01-02 04:00:00-05'::timestamp with time zone) AND (start_time <= '2019-01-02 05:00:00-05'::timestamp with time zone)) > > Is there some reason why the partition constraints aren't excluding any of the > index scans ? Yeah, we don't do anything to remove base quals that are redundant due to the partition constraint. There was a patch [1] to try and fix this but it's not seen any recent activity. [1] https://commitfest.postgresql.org/19/1264/ -- David Rowley http://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Training & Services
