EXPLAIN ANALYZE on counters WITH primary key on (count_type, count_id)

counters-explain-withpk.txt

test=# explain (analyze, buffers, verbose) update counters set count = count + 1 where count_type = 0 and count_id = 1;                                                                                     
                                                   QUERY PLAN                                                   
----------------------------------------------------------------------------------------------------------------
 Update on public.counters  (cost=0.00..5.03 rows=1 width=18) (actual time=0.036..0.036 rows=0 loops=1)
   Buffers: shared hit=6
   ->  Seq Scan on public.counters  (cost=0.00..5.03 rows=1 width=18) (actual time=0.020..0.021 rows=1 loops=1)
         Output: count_type, count_id, (count + 1), ctid
         Filter: ((counters.count_type = 0) AND (counters.count_id = 1))
         Rows Removed by Filter: 4
         Buffers: shared hit=5
 Total runtime: 0.059 ms
(8 rows)