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782514a0f1
We have an index on Notifications(service_id, created_at), by updating the query to use between created_at rather than date(created_at) this query will use the index. Changing the query plan to use an index scan rather than a sequence scan, see query plans below. This query is still rather slow but is improved by this update. https://www.pivotaltracker.com/story/show/178263480 explain analyze SELECT notification_type, notification_status, count(id) FROM notifications WHERE service_id = 'e791dbd4-09ea-413a-b773-ead8728ddb09' AND date(created_at) = '2021-05-23' AND key_type != 'test' GROUP BY notification_type, notification_status; QUERY PLAN ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ Finalize GroupAggregate (cost=6326816.31..6326926.48 rows=24 width=22) (actual time=91666.805..91712.976 rows=10 loops=1) Group Key: notification_type, notification_status -> Gather Merge (cost=6326816.31..6326925.88 rows=48 width=22) (actual time=91666.712..91712.962 rows=30 loops=1) Workers Planned: 2 Workers Launched: 2 -> Partial GroupAggregate (cost=6325816.28..6325920.31 rows=24 width=22) (actual time=91662.907..91707.027 rows=10 loops=3) Group Key: notification_type, notification_status -> Sort (cost=6325816.28..6325842.23 rows=10379 width=30) (actual time=91635.890..91676.225 rows=270884 loops=3) Sort Key: notification_type, notification_status Sort Method: external merge Disk: 10584kB Worker 0: Sort Method: external merge Disk: 10648kB Worker 1: Sort Method: external merge Disk: 10696kB -> Parallel Seq Scan on notifications (cost=0.00..6325123.93 rows=10379 width=30) (actual time=0.036..91513.985 rows=270884 loops=3) Filter: (((key_type)::text <> 'test'::text) AND (service_id = 'e791dbd4-09ea-413a-b773-ead8728ddb09'::uuid) AND (date(created_at) = '2021-05-23'::date)) Rows Removed by Filter: 16191366 Planning Time: 0.760 ms Execution Time: 91714.500 ms (17 rows) explain analyze SELECT notification_type, notification_status, count(id) FROM notifications WHERE service_id = 'e791dbd4-09ea-413a-b773-ead8728ddb09' AND created_at >= '2021-05-22 23:00' and created_at < '2021-05-23 23:00' AND key_type != 'test' GROUP BY notification_type, notification_status; QUERY PLAN -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Finalize GroupAggregate (cost=2114273.37..2114279.57 rows=24 width=22) (actual time=21032.076..21035.725 rows=10 loops=1) Group Key: notification_type, notification_status -> Gather Merge (cost=2114273.37..2114278.97 rows=48 width=22) (actual time=21032.056..21035.703 rows=30 loops=1) Workers Planned: 2 Workers Launched: 2 -> Sort (cost=2113273.35..2113273.41 rows=24 width=22) (actual time=21029.261..21029.265 rows=10 loops=3) Sort Key: notification_type, notification_status Sort Method: quicksort Memory: 25kB Worker 0: Sort Method: quicksort Memory: 25kB Worker 1: Sort Method: quicksort Memory: 25kB -> Partial HashAggregate (cost=2113272.56..2113272.80 rows=24 width=22) (actual time=21029.228..21029.230 rows=10 loops=3) Group Key: notification_type, notification_status -> Parallel Bitmap Heap Scan on notifications (cost=114455.71..2111695.14 rows=210322 width=30) (actual time=4983.790..20960.581 rows=271217 loops=3) Recheck Cond: ((service_id = 'e791dbd4-09ea-413a-b773-ead8728ddb09'::uuid) AND (created_at >= '2021-05-22 23:00:00'::timestamp without time zone) AND (created_at < '2021-05-23 23:00:00'::timestamp without time zone)) Rows Removed by Index Recheck: 1456269 Filter: ((key_type)::text <> 'test'::text) Heap Blocks: exact=12330 lossy=123418 -> Bitmap Index Scan on ix_notifications_service_created_at (cost=0.00..114329.51 rows=543116 width=0) (actual time=4973.139..4973.140 rows=813671 loops=1) Index Cond: ((service_id = 'e791dbd4-09ea-413a-b773-ead8728ddb09'::uuid) AND (created_at >= '2021-05-22 23:00:00'::timestamp without time zone) AND (created_at < '2021-05-23 23:00:00'::timestamp without time zone)) Planning Time: 0.191 ms Execution Time: 21035.770 ms (21 rows)