QUERY PLAN
Finalize Aggregate (cost=4966.61..4966.62 rows=1 width=8)
-> Gather (cost=4966.50..4966.61 rows=1 width=8)
Workers Planned: 1
-> Partial Aggregate (cost=3966.50..3966.51 rows=1 width=8)
-> Nested Loop (cost=0.42..3966.46 rows=16 width=0)
-> Parallel Seq Scan on tbl_unread_comments uc (cost=0.00..3806.15 rows=19 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