QUERY PLAN
Sort (cost=23778.64..23784.75 rows=2444 width=18)
Sort Key: c.object_type
-> HashAggregate (cost=23616.66..23641.10 rows=2444 width=18)
Group Key: c.object_type, sub.unreadcount
-> Hash Left Join (cost=18224.37..23576.39 rows=8054 width=10)
Hash Cond: ((c.object_type)::text = (sub.object_type)::text)
-> Hash Right Join (cost=7365.19..12694.34 rows=8054 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..5223.45 rows=40269 width=8)
Filter: (remind_user_id = 1001)
-> Hash (cost=6931.60..6931.60 rows=34687 width=10)
-> Seq Scan on tbl_comments c (cost=0.00..6931.60 rows=34687 width=10)
Filter: (NOT is_system)
-> Hash (cost=10858.59..10858.59 rows=47 width=11)
-> Subquery Scan on sub (cost=10850.14..10858.59 rows=47 width=11)
-> Finalize GroupAggregate (cost=10850.14..10858.12 rows=47 width=11)
Group Key: uc_1.object_type
-> Gather Merge (cost=10850.14..10857.42 rows=47 width=11)
Workers Planned: 1
-> Partial GroupAggregate (cost=9850.13..9852.12 rows=47 width=11)
Group Key: uc_1.object_type
-> Sort (cost=9850.13..9850.64 rows=202 width=3)
Sort Key: uc_1.object_type
-> Nested Loop (cost=0.42..9842.40 rows=202 width=3)
-> Parallel Seq Scan on tbl_unread_comments uc_1 (cost=0.00..3801.85 rows=1252 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..4.82 rows=1 width=4)
Index Cond: (id = uc_1.comment_id)
Filter: (NOT is_system)