QUERY PLAN
Finalize Aggregate (cost=4919.59..4919.60 rows=1 width=8)
-> Gather (cost=4919.48..4919.59 rows=1 width=8)
Workers Planned: 1
-> Partial Aggregate (cost=3919.48..3919.49 rows=1 width=8)
-> Nested Loop (cost=0.42..3919.44 rows=14 width=0)
-> Parallel Seq Scan on tbl_unread_comments uc (cost=0.00..3784.44 rows=16 width=4)
Filter: ((NOT is_read) AND (remind_user_id = 1000))
-> Index Scan using tbl_comments_pkey on tbl_comments c (cost=0.42..8.44 rows=1 width=4)
Index Cond: (id = uc.comment_id)
Filter: is_system