QUERY PLAN
GroupAggregate (cost=332.46..333.88 rows=78 width=12)
Group Key: client_id
-> Sort (cost=332.46..332.67 rows=86 width=8)
Sort Key: client_id
-> Seq Scan on tbl_cases (cost=0.00..329.69 rows=86 width=8)
Filter: (client_id = ANY ('{399,1661,2120,2162,2169,1465,2147,1283,2095,39}'::integer[]))