QUERY PLAN
Aggregate (cost=157.12..157.13 rows=1 width=8)
-> Sort (cost=156.86..156.91 rows=17 width=231)
Sort Key: s.status, u.pinyin_shortcut, s.target_completed_at, s.updated_at DESC
-> Group (cost=156.39..156.52 rows=17 width=231)
Group Key: s.id, u.id
-> Sort (cost=156.39..156.43 rows=17 width=29)
Sort Key: s.id, u.id
-> Hash Left Join (cost=9.17..156.04 rows=17 width=29)
Hash Cond: (s.head_of = u.id)
-> Seq Scan on tbl_tasks s (cost=0.00..146.82 rows=17 width=34)
Filter: (task_group_id = 65)
-> Hash (cost=7.41..7.41 rows=141 width=7)
-> Seq Scan on tbl_users u (cost=0.00..7.41 rows=141 width=7)