QUERY PLAN
GroupAggregate (cost=94.65..94.67 rows=1 width=12)
Group Key: case_id
-> Sort (cost=94.65..94.65 rows=1 width=4)
Sort Key: case_id
-> Seq Scan on tbl_pre_sales (cost=0.00..94.64 rows=1 width=4)
Filter: ((created_by = 1000) AND (case_id = ANY ('{8267,8266,8265,8260}'::integer[])))