QUERY PLAN
Finalize Aggregate (cost=4970.87..4970.88 rows=1 width=8)
-> Gather (cost=4970.76..4970.87 rows=1 width=8)
Workers Planned: 1
-> Partial Aggregate (cost=3970.76..3970.77 rows=1 width=8)
-> Nested Loop (cost=0.42..3970.75 rows=3 width=0)
-> Parallel Seq Scan on tbl_unread_comments uc (cost=0.00..3810.44 rows=19 width=4)
Filter: ((NOT is_read) AND (remind_user_id = 5250))
-> 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: (NOT is_system)