BEGIN;
BEGIN
EXPLAIN (ANALYZE, BUFFERS)
select
	l_shipmode,
	sum(case
		when o_orderpriority = '1-URGENT'
			or o_orderpriority = '2-HIGH'
			then 1
		else 0
	end) as high_line_count,
	sum(case
		when o_orderpriority <> '1-URGENT'
			and o_orderpriority <> '2-HIGH'
			then 1
		else 0
	end) as low_line_count
from
	orders,
	lineitem
where
	o_orderkey = l_orderkey
	and l_shipmode in ('RAIL', 'AIR')
	and l_commitdate < l_receiptdate
	and l_shipdate < l_commitdate
	and l_receiptdate >= date '1997-01-01'
	and l_receiptdate < date '1997-01-01' + interval '1 year'
group by
	l_shipmode
order by
	l_shipmode;
                                                                                          QUERY PLAN                                                                                          
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 Sort  (cost=982844.78..982844.79 rows=1 width=27) (actual time=40156.612..40156.612 rows=2 loops=1)
   Sort Key: lineitem.l_shipmode
   Sort Method: quicksort  Memory: 25kB
   Buffers: shared hit=695042 read=668969 dirtied=939 written=27282
   ->  HashAggregate  (cost=982844.76..982844.77 rows=1 width=27) (actual time=40156.491..40156.492 rows=2 loops=1)
         Buffers: shared hit=695037 read=668969 dirtied=939 written=27282
         ->  Hash Join  (cost=592539.42..977764.48 rows=290302 width=27) (actual time=17066.319..39541.875 rows=311791 loops=1)
               Hash Cond: (lineitem.l_orderkey = orders.o_orderkey)
               Buffers: shared hit=695037 read=668969 dirtied=939 written=27282
               ->  Index Scan using lineitem_l_orderkey_idx_part2 on lineitem  (cost=0.00..376153.12 rows=290302 width=15) (actual time=0.314..20977.642 rows=311791 loops=1)
                     Filter: ((l_shipmode = ANY ('{RAIL,AIR}'::bpchar[])) AND (l_receiptdate >= '1997-01-01'::date) AND (l_receiptdate < '1998-01-01 00:00:00'::timestamp without time zone))
                     Rows Removed by Filter: 6885460
                     Buffers: shared hit=466971 read=643004 dirtied=939 written=27282
               ->  Hash  (cost=404477.52..404477.52 rows=15044952 width=20) (actual time=17046.399..17046.399 rows=15015000 loops=1)
                     Buckets: 2097152  Batches: 1  Memory Usage: 762481kB
                     Buffers: shared hit=228063 read=25965
                     ->  Seq Scan on orders  (cost=0.00..404477.52 rows=15044952 width=20) (actual time=0.019..6909.604 rows=15015000 loops=1)
                           Buffers: shared hit=228063 read=25965
 Total runtime: 40330.810 ms
(19 rows)

COMMIT;
COMMIT