"Aggregate  (cost=21166.32..21166.33 rows=1 width=8) (actual time=87.265..87.266 rows=1 loops=1)"
"  Output: count(*)"
"  Buffers: shared hit=4885"
"  ->  Bitmap Heap Scan on public.mytable  (cost=7599.68..21155.90 rows=4166 width=0) (actual time=80.274..86.811 rows=3890 loops=1)"
"        Recheck Cond: (((mytable.c = 3) OR (mytable.d = 4)) AND ((mytable.a = 1) OR (mytable.b = 2)))"
"        Heap Blocks: exact=3782"
"        Buffers: shared hit=4885"
"        ->  BitmapAnd  (cost=7599.68..7599.68 rows=4209 width=0) (actual time=78.628..78.628 rows=0 loops=1)"
"              Buffers: shared hit=1103"
"              ->  BitmapOr  (cost=3796.47..3796.47 rows=205002 width=0) (actual time=42.314..42.314 rows=0 loops=1)"
"                    Buffers: shared hit=551"
"                    ->  Bitmap Index Scan on c  (cost=0.00..1856.94 rows=100334 width=0) (actual time=30.602..30.602 rows=99580 loops=1)"
"                          Index Cond: (mytable.c = 3)"
"                          Buffers: shared hit=275"
"                    ->  Bitmap Index Scan on d  (cost=0.00..1937.44 rows=104668 width=0) (actual time=11.707..11.707 rows=99981 loops=1)"
"                          Index Cond: (mytable.d = 4)"
"                          Buffers: shared hit=276"
"              ->  BitmapOr  (cost=3802.97..3802.97 rows=205335 width=0) (actual time=30.455..30.455 rows=0 loops=1)"
"                    Buffers: shared hit=552"
"                    ->  Bitmap Index Scan on a  (cost=0.00..1937.44 rows=104668 width=0) (actual time=17.524..17.524 rows=99931 loops=1)"
"                          Index Cond: (mytable.a = 1)"
"                          Buffers: shared hit=276"
"                    ->  Bitmap Index Scan on b  (cost=0.00..1863.44 rows=100667 width=0) (actual time=12.923..12.923 rows=99923 loops=1)"
"                          Index Cond: (mytable.b = 2)"
"                          Buffers: shared hit=276"
"Planning Time: 0.240 ms"
"Execution Time: 87.358 ms"

"Aggregate  (cost=13454.71..13454.72 rows=1 width=8) (actual time=8.351..8.352 rows=1 loops=1)"
"  Output: count(*)"
"  Buffers: shared hit=3804"
"  ->  Bitmap Heap Scan on public.mytable  (cost=99.04..13444.41 rows=4118 width=0) (actual time=1.440..7.945 rows=3890 loops=1)"
"        Recheck Cond: (((mytable.a = 1) AND (mytable.c = 3)) OR ((mytable.b = 2) AND (mytable.c = 3)) OR ((mytable.a = 1) AND (mytable.d = 4)) OR ((mytable.b = 2) AND (mytable.d = 4)))"
"        Heap Blocks: exact=3782"
"        Buffers: shared hit=3804"
"        ->  BitmapOr  (cost=99.04..99.04 rows=4119 width=0) (actual time=0.897..0.897 rows=0 loops=1)"
"              Buffers: shared hit=22"
"              ->  Bitmap Index Scan on ac  (cost=0.00..21.59 rows=916 width=0) (actual time=0.223..0.223 rows=998 loops=1)"
"                    Index Cond: ((mytable.a = 1) AND (mytable.c = 3))"
"                    Buffers: shared hit=6"
"              ->  Bitmap Index Scan on bc  (cost=0.00..22.11 rows=967 width=0) (actual time=0.211..0.211 rows=980 loops=1)"
"                    Index Cond: ((mytable.b = 2) AND (mytable.c = 3))"
"                    Buffers: shared hit=5"
"              ->  Bitmap Index Scan on ad  (cost=0.00..23.30 rows=1087 width=0) (actual time=0.136..0.136 rows=963 loops=1)"
"                    Index Cond: ((mytable.a = 1) AND (mytable.d = 4))"
"                    Buffers: shared hit=5"
"              ->  Bitmap Index Scan on bd  (cost=0.00..27.91 rows=1148 width=0) (actual time=0.325..0.325 rows=978 loops=1)"
"                    Index Cond: ((mytable.b = 2) AND (mytable.d = 4))"
"                    Buffers: shared hit=6"
"Planning Time: 0.209 ms"
"Execution Time: 8.434 ms"

Aggregate  (cost=906.77..906.78 rows=1 width=8) (actual time=16.878..16.879 rows=1 loops=1)
  Output: count(*)
  Buffers: shared hit=166
  ->  Bitmap Heap Scan on public.mytable  (cost=748.67..906.67 rows=40 width=0) (actual time=16.728..16.863 rows=46 loops=1)
        Recheck Cond: (((mytable.a = 1) OR (mytable.b = 2)) AND ((mytable.c = 3) OR (mytable.d = 4)))
        Heap Blocks: exact=46
        Buffers: shared hit=166
        ->  BitmapAnd  (cost=748.67..748.67 rows=40 width=0) (actual time=16.524..16.524 rows=0 loops=1)
              Buffers: shared hit=120
              ->  BitmapOr  (cost=374.15..374.15 rows=19901 width=0) (actual time=7.290..7.290 rows=0 loops=1)
                    Buffers: shared hit=60
                    ->  Bitmap Index Scan on a  (cost=0.00..187.02 rows=9945 width=0) (actual time=3.577..3.577 rows=10083 loops=1)
                          Index Cond: (mytable.a = 1)
                          Buffers: shared hit=30
                    ->  Bitmap Index Scan on b  (cost=0.00..187.11 rows=9956 width=0) (actual time=3.709..3.709 rows=9963 loops=1)
                          Index Cond: (mytable.b = 2)
                          Buffers: shared hit=30
              ->  BitmapOr  (cost=374.27..374.27 rows=19918 width=0) (actual time=7.196..7.196 rows=0 loops=1)
                    Buffers: shared hit=60
                    ->  Bitmap Index Scan on c  (cost=0.00..187.17 rows=9965 width=0) (actual time=3.748..3.748 rows=9915 loops=1)
                          Index Cond: (mytable.c = 3)
                          Buffers: shared hit=30
                    ->  Bitmap Index Scan on d  (cost=0.00..187.08 rows=9953 width=0) (actual time=3.444..3.445 rows=9945 loops=1)
                          Index Cond: (mytable.d = 4)
                          Buffers: shared hit=30
Planning Time: 0.206 ms
Execution Time: 16.949 ms

Aggregate  (cost=176.68..176.69 rows=1 width=8) (actual time=0.334..0.335 rows=1 loops=1)	
  Output: count(*)	
  Buffers: shared hit=58	
  ->  Bitmap Heap Scan on public.mytable  (cost=18.18..176.58 rows=40 width=0) (actual time=0.161..0.315 rows=46 loops=1)	
        Recheck Cond: (((mytable.a = 1) AND (mytable.c = 3)) OR ((mytable.b = 2) AND (mytable.c = 3)) OR ((mytable.a = 1) AND (mytable.d = 4)) OR ((mytable.b = 2) AND (mytable.d = 4)))	
        Heap Blocks: exact=46	
        Buffers: shared hit=58	
        ->  BitmapOr  (cost=18.18..18.18 rows=40 width=0) (actual time=0.138..0.138 rows=0 loops=1)	
              Buffers: shared hit=12	
              ->  Bitmap Index Scan on ac  (cost=0.00..4.53 rows=10 width=0) (actual time=0.039..0.040 rows=11 loops=1)	
                    Index Cond: ((mytable.a = 1) AND (mytable.c = 3))	
                    Buffers: shared hit=3	
              ->  Bitmap Index Scan on bc  (cost=0.00..4.53 rows=10 width=0) (actual time=0.023..0.023 rows=10 loops=1)	
                    Index Cond: ((mytable.b = 2) AND (mytable.c = 3))	
                    Buffers: shared hit=3	
              ->  Bitmap Index Scan on ad  (cost=0.00..4.53 rows=10 width=0) (actual time=0.057..0.057 rows=11 loops=1)	
                    Index Cond: ((mytable.a = 1) AND (mytable.d = 4))	
                    Buffers: shared hit=3	
              ->  Bitmap Index Scan on bd  (cost=0.00..4.53 rows=10 width=0) (actual time=0.016..0.016 rows=14 loops=1)	
                    Index Cond: ((mytable.b = 2) AND (mytable.d = 4))	
                    Buffers: shared hit=3	
Planning Time: 0.363 ms	
Execution Time: 0.410 ms