QUERY PLAN
Sort (cost=28156.13..28162.97 rows=2736 width=18)
Sort Key: c.object_type
-> HashAggregate (cost=27972.57..27999.93 rows=2736 width=18)
Group Key: c.object_type, sub.unreadcount
-> Hash Left Join (cost=21143.78..27763.60 rows=41795 width=10)
Hash Cond: ((c.object_type)::text = (sub.object_type)::text)
-> Hash Right Join (cost=10076.41..16578.36 rows=41795 width=2)
Hash Cond: (uc.comment_id = c.id)
Filter: ((uc.remind_user_id = 1001) OR (c.created_by = 1001))
-> Seq Scan on tbl_unread_comments uc (cost=0.00..5202.40 rows=39830 width=8)
Filter: (remind_user_id = 1001)
-> Hash (cost=6934.61..6934.61 rows=180704 width=10)
-> Seq Scan on tbl_comments c (cost=0.00..6934.61 rows=180704 width=10)
Filter: is_system
-> Hash (cost=11066.77..11066.77 rows=48 width=11)
-> Subquery Scan on sub (cost=11051.47..11066.77 rows=48 width=11)
-> Finalize GroupAggregate (cost=11051.47..11066.29 rows=48 width=11)
Group Key: uc_1.object_type
-> Gather Merge (cost=11051.47..11065.57 rows=48 width=11)
Workers Planned: 1
-> Partial GroupAggregate (cost=10051.46..10060.16 rows=48 width=11)
Group Key: uc_1.object_type
-> Sort (cost=10051.46..10054.20 rows=1096 width=3)
Sort Key: uc_1.object_type
-> Nested Loop (cost=0.42..9996.12 rows=1096 width=3)
-> Parallel Seq Scan on tbl_unread_comments uc_1 (cost=0.00..3786.59 rows=1306 width=7)
Filter: ((NOT is_read) AND (remind_user_id = 1001))
-> Index Scan using tbl_comments_pkey on tbl_comments c_1 (cost=0.42..4.75 rows=1 width=4)
Index Cond: (id = uc_1.comment_id)
Filter: is_system