BEGIN; BEGIN EXPLAIN (ANALYZE, BUFFERS) select s_name, count(*) as numwait from supplier, lineitem l1, orders, nation where s_suppkey = l1.l_suppkey and o_orderkey = l1.l_orderkey and o_orderstatus = 'F' and l1.l_receiptdate > l1.l_commitdate and exists ( select * from lineitem l2 where l2.l_orderkey = l1.l_orderkey and l2.l_suppkey <> l1.l_suppkey ) and not exists ( select * from lineitem l3 where l3.l_orderkey = l1.l_orderkey and l3.l_suppkey <> l1.l_suppkey and l3.l_receiptdate > l3.l_commitdate ) and s_nationkey = n_nationkey and n_name = 'CHINA' group by s_name order by numwait desc, s_name LIMIT 100; QUERY PLAN ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ Limit (cost=1952672.94..1952672.94 rows=1 width=26) (actual time=50662.398..50662.419 rows=100 loops=1) Buffers: shared hit=13723729 read=801718 written=4595 -> Sort (cost=1952672.94..1952672.94 rows=1 width=26) (actual time=50662.395..50662.403 rows=100 loops=1) Sort Key: (count(*)), supplier.s_name Sort Method: top-N heapsort Memory: 32kB Buffers: shared hit=13723729 read=801718 written=4595 -> HashAggregate (cost=1952672.92..1952672.93 rows=1 width=26) (actual time=50659.749..50661.169 rows=3988 loops=1) Group Key: supplier.s_name Buffers: shared hit=13723721 read=801718 written=4595 -> Nested Loop Anti Join (cost=2443.74..1952672.91 rows=1 width=26) (actual time=18.457..50580.913 rows=39923 loops=1) Buffers: shared hit=13723721 read=801718 written=4595 -> Nested Loop Semi Join (cost=2443.17..1952671.61 rows=1 width=34) (actual time=18.268..47101.013 rows=705190 loops=1) Join Filter: (orders.o_orderkey = l2.l_orderkey) Buffers: shared hit=10191557 read=799682 written=4585 -> Nested Loop (cost=2442.61..1433336.65 rows=388697 width=38) (actual time=18.174..40768.450 rows=731492 loops=1) Buffers: shared hit=6690087 read=637598 written=3612 -> Hash Join (cost=2442.17..1011465.62 rows=801411 width=34) (actual time=18.068..30482.493 rows=1512908 loops=1) Hash Cond: (l1.l_suppkey = supplier.s_suppkey) Buffers: shared hit=690483 read=577312 written=3255 -> Index Scan using lineitem_l_orderkey_idx_part1 on lineitem l1 (cost=0.56..925877.67 rows=20035263 width=8) (actual time=0.089..21658.148 rows=37928740 loops=1) Buffers: shared hit=688642 read=577299 written=3255 -> Hash (cost=2391.61..2391.61 rows=4000 width=30) (actual time=17.928..17.928 rows=3988 loops=1) Buckets: 4096 Batches: 1 Memory Usage: 282kB Buffers: shared hit=1838 read=13 -> Nested Loop (cost=79.29..2391.61 rows=4000 width=30) (actual time=1.281..16.754 rows=3988 loops=1) Buffers: shared hit=1838 read=13 -> Seq Scan on nation (cost=0.00..1.31 rows=1 width=4) (actual time=0.012..0.017 rows=1 loops=1) Filter: (n_name = 'CHINA'::bpchar) Rows Removed by Filter: 24 Buffers: shared hit=1 -> Bitmap Heap Scan on supplier (cost=79.29..2350.29 rows=4000 width=34) (actual time=1.262..15.898 rows=3988 loops=1) Recheck Cond: (s_nationkey = nation.n_nationkey) Heap Blocks: exact=1837 Buffers: shared hit=1837 read=13 -> Bitmap Index Scan on supplier_s_nationkey_s_suppkey_idx (cost=0.00..78.29 rows=4000 width=0) (actual time=0.965..0.965 rows=3988 loops=1) Index Cond: (s_nationkey = nation.n_nationkey) Buffers: shared read=13 -> Index Scan using orders_o_orderkey_o_orderdate_idx on orders (cost=0.43..0.52 rows=1 width=4) (actual time=0.006..0.006 rows=0 loops=1512908) Index Cond: (o_orderkey = l1.l_orderkey) Filter: (o_orderstatus = 'F'::bpchar) Rows Removed by Filter: 1 Buffers: shared hit=5999604 read=60286 written=357 -> Index Scan using lineitem_l_orderkey_idx on lineitem l2 (cost=0.56..1.15 rows=15 width=8) (actual time=0.008..0.008 rows=1 loops=731492) Index Cond: (l_orderkey = l1.l_orderkey) Filter: (l_suppkey <> l1.l_suppkey) Rows Removed by Filter: 0 Buffers: shared hit=3501470 read=162084 written=973 -> Index Scan using lineitem_l_orderkey_idx_part1 on lineitem l3 (cost=0.56..0.91 rows=5 width=8) (actual time=0.004..0.004 rows=1 loops=705190) Index Cond: (l_orderkey = l1.l_orderkey) Filter: (l_suppkey <> l1.l_suppkey) Rows Removed by Filter: 0 Buffers: shared hit=3532164 read=2036 written=10 Planning time: 10.799 ms Execution time: 50662.820 ms (54 rows) COMMIT; COMMIT