QUERY PLAN
Sort (cost=20709.53..20711.28 rows=700 width=18)
Sort Key: c.object_type
-> HashAggregate (cost=20669.45..20676.45 rows=700 width=18)
Group Key: c.object_type, sub.unreadcount
-> Hash Left Join (cost=15243.08..20604.03 rows=13084 width=10)
Hash Cond: ((c.object_type)::text = (sub.object_type)::text)
-> Hash Right Join (cost=8485.57..13806.98 rows=13084 width=2)
Hash Cond: (uc.comment_id = c.id)
Filter: ((uc.remind_user_id = 1004) OR (c.created_by = 1004))
-> Seq Scan on tbl_unread_comments uc (cost=0.00..4467.15 rows=13052 width=8)
Filter: (remind_user_id = 1004)
-> Hash (cost=5930.98..5930.98 rows=146927 width=10)
-> Seq Scan on tbl_comments c (cost=0.00..5930.98 rows=146927 width=10)
Filter: is_system
-> Hash (cost=6757.20..6757.20 rows=25 width=10)
-> Subquery Scan on sub (cost=6751.22..6757.20 rows=25 width=10)
-> Finalize GroupAggregate (cost=6751.22..6756.95 rows=25 width=10)
Group Key: uc_1.object_type
-> Gather Merge (cost=6751.22..6756.58 rows=25 width=10)
Workers Planned: 1
-> Partial GroupAggregate (cost=5751.21..5753.75 rows=25 width=10)
Group Key: uc_1.object_type
-> Sort (cost=5751.21..5751.97 rows=306 width=2)
Sort Key: uc_1.object_type
-> Nested Loop (cost=0.42..5738.57 rows=306 width=2)
-> Parallel Seq Scan on tbl_unread_comments uc_1 (cost=0.00..3248.68 rows=378 width=6)
Filter: ((NOT is_read) AND (remind_user_id = 1004))
-> Index Scan using tbl_comments_pkey on tbl_comments c_1 (cost=0.42..6.59 rows=1 width=4)
Index Cond: (id = uc_1.comment_id)
Filter: is_system