QUERY PLAN
GroupAggregate (cost=354.56..356.02 rows=80 width=12)
Group Key: client_id
-> Sort (cost=354.56..354.78 rows=89 width=8)
Sort Key: client_id
-> Seq Scan on tbl_cases (cost=0.00..351.67 rows=89 width=8)
Filter: (client_id = ANY ('{3331,3290,2153,42,2131,2213,111,33,2118,122}'::integer[]))