QUERY PLAN
GroupAggregate (cost=330.93..331.70 rows=43 width=12)
Group Key: client_id
-> Sort (cost=330.93..331.04 rows=45 width=8)
Sort Key: client_id
-> Seq Scan on tbl_cases (cost=0.00..329.69 rows=45 width=8)
Filter: (client_id = ANY ('{399,1661,2120,2162,2169,622,2152,1465,2147,1283}'::integer[]))