QUERY PLAN
GroupAggregate (cost=94.71..94.82 rows=6 width=12)
Group Key: case_id
-> Sort (cost=94.71..94.73 rows=6 width=4)
Sort Key: case_id
-> Seq Scan on tbl_pre_sales (cost=0.00..94.64 rows=6 width=4)
Filter: (case_id = ANY ('{8250,8258,8255,8253,8245,8248}'::integer[]))