QUERY PLAN
Group (cost=16734.75..16738.25 rows=448 width=18)
Group Key: c.object_type, sub.unreadcount
-> Sort (cost=16734.75..16735.92 rows=467 width=10)
Sort Key: c.object_type, sub.unreadcount
-> Hash Left Join (cost=11890.22..16714.05 rows=467 width=10)
Hash Cond: ((c.object_type)::text = (sub.object_type)::text)
-> Hash Right Join (cost=7732.27..12554.68 rows=467 width=2)
Hash Cond: (uc.comment_id = c.id)
Filter: ((uc.remind_user_id = 5250) OR (c.created_by = 5250))
-> Seq Scan on tbl_unread_comments uc (cost=0.00..4165.14 rows=484 width=8)
Filter: (remind_user_id = 5250)
-> Hash (cost=5413.41..5413.41 rows=133349 width=10)
-> Seq Scan on tbl_comments c (cost=0.00..5413.41 rows=133349 width=10)
Filter: is_system
-> Hash (cost=4157.75..4157.75 rows=16 width=10)
-> Subquery Scan on sub (cost=4155.81..4157.75 rows=16 width=10)
-> Finalize GroupAggregate (cost=4155.81..4157.59 rows=16 width=10)
Group Key: uc_1.object_type
-> Gather Merge (cost=4155.81..4157.37 rows=12 width=10)
Workers Planned: 1
-> Partial GroupAggregate (cost=3155.80..3156.01 rows=12 width=10)
Group Key: uc_1.object_type
-> Sort (cost=3155.80..3155.83 rows=12 width=2)
Sort Key: uc_1.object_type
-> Nested Loop (cost=0.42..3155.58 rows=12 width=2)
-> Parallel Seq Scan on tbl_unread_comments uc_1 (cost=0.00..3029.02 rows=15 width=6)
Filter: ((NOT is_read) AND (remind_user_id = 5250))
-> Index Scan using tbl_comments_pkey on tbl_comments c_1 (cost=0.42..8.44 rows=1 width=4)
Index Cond: (id = uc_1.comment_id)
Filter: is_system