QUERY PLAN
Finalize Aggregate (cost=6644.01..6644.02 rows=1 width=8)
-> Gather (cost=6643.90..6644.01 rows=1 width=8)
Workers Planned: 1
-> Partial Aggregate (cost=5643.90..5643.91 rows=1 width=8)
-> Nested Loop (cost=0.42..5643.15 rows=298 width=0)
-> Parallel Seq Scan on tbl_unread_comments uc (cost=0.00..3231.58 rows=364 width=4)
Filter: ((NOT is_read) AND (remind_user_id = 5252))
-> Index Scan using tbl_comments_pkey on tbl_comments c (cost=0.42..6.63 rows=1 width=4)
Index Cond: (id = uc.comment_id)
Filter: is_system