BEGIN;
BEGIN
EXPLAIN (ANALYZE, BUFFERS)
select
	nation,
	o_year,
	sum(amount) as sum_profit
from
	(
		select
			n_name as nation,
			extract(year from o_orderdate) as o_year,
			l_extendedprice * (1 - l_discount) - ps_supplycost * l_quantity as amount
		from
			part,
			supplier,
			lineitem,
			partsupp,
			orders,
			nation
		where
			s_suppkey = l_suppkey
			and ps_suppkey = l_suppkey
			and ps_partkey = l_partkey
			and p_partkey = l_partkey
			and o_orderkey = l_orderkey
			and s_nationkey = n_nationkey
			and p_name like '%coral%'
	) as profit
group by
	nation,
	o_year
order by
	nation,
	o_year desc;
                                                                                   QUERY PLAN                                                                                   
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 GroupAggregate  (cost=3523174.98..3523179.99 rows=143 width=46) (actual time=655567.273..659098.207 rows=175 loops=1)
   Buffers: shared hit=30497024 read=489074 dirtied=11 written=1741
   ->  Sort  (cost=3523174.98..3523175.34 rows=143 width=46) (actual time=655552.406..656520.519 rows=3266801 loops=1)
         Sort Key: nation.n_name, (date_part('year'::text, (orders.o_orderdate)::timestamp without time zone))
         Sort Method: quicksort  Memory: 557698kB
         Buffers: shared hit=30497024 read=489074 dirtied=11 written=1741
         ->  Nested Loop  (cost=2852904.45..3523169.87 rows=143 width=46) (actual time=197458.307..633941.045 rows=3266801 loops=1)
               Buffers: shared hit=30497016 read=489074 dirtied=11 written=1741
               ->  Nested Loop  (cost=2852904.45..3523129.08 rows=143 width=24) (actual time=197456.894..529488.921 rows=3266801 loops=1)
                     Buffers: shared hit=23963414 read=489074 dirtied=11 written=1741
                     ->  Nested Loop  (cost=2852904.45..3522846.73 rows=143 width=24) (actual time=197456.796..324362.813 rows=3266801 loops=1)
                           Buffers: shared hit=11018874 read=348768 dirtied=4 written=165
                           ->  Merge Join  (cost=2852904.45..3522805.09 rows=143 width=28) (actual time=197456.222..217207.659 rows=3266801 loops=1)
                                 Merge Cond: ((partsupp.ps_partkey = lineitem.l_partkey) AND (partsupp.ps_suppkey = lineitem.l_suppkey))
                                 Buffers: shared hit=1200945 read=348768 dirtied=4 written=165
                                 ->  Index Scan using pk_partsupp on partsupp  (cost=0.00..603091.29 rows=8000000 width=12) (actual time=0.027..11146.432 rows=7999993 loops=1)
                                       Buffers: shared hit=417200 read=17009 written=160
                                 ->  Sort  (cost=2852904.42..2861840.42 rows=3574400 width=28) (actual time=197456.091..200763.833 rows=3266801 loops=1)
                                       Sort Key: part.p_partkey, lineitem.l_suppkey
                                       Sort Method: quicksort  Memory: 353523kB
                                       Buffers: shared hit=783745 read=331759 dirtied=4 written=5
                                       ->  Hash Join  (cost=66998.45..2463844.04 rows=3574400 width=28) (actual time=2577.901..193159.556 rows=3266801 loops=1)
                                             Hash Cond: (lineitem.l_partkey = part.p_partkey)
                                             Buffers: shared hit=783742 read=331759 dirtied=4 written=5
                                             ->  Seq Scan on lineitem  (cost=0.00..1680211.57 rows=60523557 width=24) (actual time=0.034..62246.456 rows=60044082 loops=1)
                                                   Buffers: shared hit=749756 read=325220 dirtied=4 written=5
                                             ->  Hash  (cost=65522.00..65522.00 rows=118116 width=4) (actual time=2577.628..2577.628 rows=108789 loops=1)
                                                   Buckets: 16384  Batches: 1  Memory Usage: 3825kB
                                                   Buffers: shared hit=33983 read=6539
                                                   ->  Seq Scan on part  (cost=0.00..65522.00 rows=118116 width=4) (actual time=0.022..2500.376 rows=108789 loops=1)
                                                         Filter: ((p_name)::text ~~ '%coral%'::text)
                                                         Rows Removed by Filter: 1891211
                                                         Buffers: shared hit=33983 read=6539
                           ->  Index Scan using pk_supplier on supplier  (cost=0.00..0.28 rows=1 width=8) (actual time=0.031..0.031 rows=1 loops=3266801)
                                 Index Cond: (s_suppkey = lineitem.l_suppkey)
                                 Buffers: shared hit=9817929
                     ->  Index Scan using pk_orders on orders  (cost=0.00..1.96 rows=1 width=8) (actual time=0.061..0.061 rows=1 loops=3266801)
                           Index Cond: (o_orderkey = lineitem.l_orderkey)
                           Buffers: shared hit=12944540 read=140306 dirtied=7 written=1576
               ->  Index Scan using pk_nation on nation  (cost=0.00..0.27 rows=1 width=30) (actual time=0.029..0.029 rows=1 loops=3266801)
                     Index Cond: (n_nationkey = supplier.s_nationkey)
                     Buffers: shared hit=6533602
 Total runtime: 659211.701 ms
(43 rows)

COMMIT;
COMMIT