BEGIN;
BEGIN
EXPLAIN (ANALYZE, BUFFERS)
select
	s_name,
	s_address
from
	supplier,
	nation
where
	s_suppkey in (
		select
			distinct (ps_suppkey)
		from
			partsupp,
			part
		where
			ps_partkey=p_partkey
			and p_name like 'purple%'
			and ps_availqty > (
				select
					0.5 * sum(l_quantity)
				from
					lineitem
				where
					l_partkey = ps_partkey
					and l_suppkey = ps_suppkey
					and l_shipdate >= '1997-01-01'
					and l_shipdate < cast(date '1997-01-01' + interval '1 year' as date)
			)
	)
	and s_nationkey = n_nationkey
	and n_name = 'CHINA'
order by
	s_name;
                                                                                                  QUERY PLAN                                                                                                   
---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 Sort  (cost=12740712.16..12740715.08 rows=1170 width=51) (actual time=15637.792..15637.911 rows=1745 loops=1)
   Sort Key: supplier.s_name
   Sort Method: quicksort  Memory: 251kB
   Buffers: shared hit=2749476 read=404538 dirtied=5558 written=433
   ->  Nested Loop  (cost=12736245.92..12740652.53 rows=1170 width=51) (actual time=15462.671..15622.036 rows=1745 loops=1)
         Join Filter: (supplier.s_nationkey = nation.n_nationkey)
         Rows Removed by Join Filter: 43273
         Buffers: shared hit=2749471 read=404538 dirtied=5558 written=433
         ->  Seq Scan on nation  (cost=0.00..1.31 rows=1 width=4) (actual time=0.013..0.022 rows=1 loops=1)
               Filter: (n_name = 'CHINA'::bpchar)
               Rows Removed by Filter: 24
               Buffers: shared hit=1
         ->  Hash Semi Join  (cost=12736245.92..12740285.46 rows=29261 width=55) (actual time=15462.629..15613.155 rows=45018 loops=1)
               Hash Cond: (supplier.s_suppkey = partsupp.ps_suppkey)
               Buffers: shared hit=2749470 read=404538 dirtied=5558 written=433
               ->  Seq Scan on supplier  (cost=0.00..3179.00 rows=100000 width=59) (actual time=0.017..47.807 rows=100000 loops=1)
                     Buffers: shared hit=2179
               ->  Hash  (cost=12735880.15..12735880.15 rows=29261 width=4) (actual time=15462.557..15462.557 rows=45018 loops=1)
                     Buckets: 4096  Batches: 1  Memory Usage: 1583kB
                     Buffers: shared hit=2747291 read=404538 dirtied=5558 written=433
                     ->  HashAggregate  (cost=12735294.93..12735587.54 rows=29261 width=4) (actual time=15414.579..15446.006 rows=45018 loops=1)
                           Buffers: shared hit=2747291 read=404538 dirtied=5558 written=433
                           ->  Nested Loop  (cost=0.00..12735221.78 rows=29261 width=4) (actual time=1.241..15289.750 rows=59728 loops=1)
                                 Buffers: shared hit=2747291 read=404538 dirtied=5558 written=433
                                 ->  Seq Scan on part  (cost=0.00..65522.00 rows=22022 width=4) (actual time=0.067..1132.302 rows=21998 loops=1)
                                       Filter: ((p_name)::text ~~ 'purple%'::text)
                                       Rows Removed by Filter: 1978002
                                       Buffers: shared hit=20342 read=20180 written=36
                                 ->  Index Scan using pk_partsupp on partsupp  (cost=0.00..575.31 rows=1 width=8) (actual time=0.510..0.641 rows=3 loops=21998)
                                       Index Cond: (ps_partkey = part.p_partkey)
                                       Filter: ((ps_availqty)::double precision > (SubPlan 1))
                                       Rows Removed by Filter: 1
                                       Buffers: shared hit=2726949 read=384358 dirtied=5558 written=397
                                       SubPlan 1
                                         ->  Aggregate  (cost=140.92..140.93 rows=1 width=4) (actual time=0.147..0.147 rows=1 loops=87992)
                                               Buffers: shared hit=2669826 read=350624 dirtied=5558 written=357
                                               ->  Index Scan using lineitem_l_partkey_l_quantity_l_shipmode_idx on lineitem  (cost=0.00..140.92 rows=1 width=4) (actual time=0.091..0.145 rows=1 loops=87992)
                                                     Index Cond: (l_partkey = partsupp.ps_partkey)
                                                     Filter: ((l_shipdate >= '1997-01-01'::date) AND (l_shipdate < '1998-01-01'::date) AND (l_suppkey = partsupp.ps_suppkey))
                                                     Rows Removed by Filter: 29
                                                     Buffers: shared hit=2669826 read=350624 dirtied=5558 written=357
 Total runtime: 15639.862 ms
(42 rows)

COMMIT;
COMMIT