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 ('MAIL', 'AIR')
	and l_commitdate < l_receiptdate
	and l_shipdate < l_commitdate
	and l_receiptdate >= date '1994-01-01'
	and l_receiptdate < date '1994-01-01' + interval '1 year'
group by
	l_shipmode
order by
	l_shipmode;
                                                                                          QUERY PLAN                                                                                          
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 Sort  (cost=983439.51..983439.51 rows=1 width=27) (actual time=37055.202..37055.203 rows=2 loops=1)
   Sort Key: lineitem.l_shipmode
   Sort Method: quicksort  Memory: 25kB
   Buffers: shared hit=443458 read=923323 dirtied=615 written=29819
   ->  HashAggregate  (cost=983439.49..983439.50 rows=1 width=27) (actual time=37055.096..37055.097 rows=2 loops=1)
         Buffers: shared hit=443453 read=923323 dirtied=615 written=29819
         ->  Hash Join  (cost=593129.56..978355.86 rows=290493 width=27) (actual time=16697.007..36545.070 rows=311082 loops=1)
               Hash Cond: (lineitem.l_orderkey = orders.o_orderkey)
               Buffers: shared hit=443453 read=923323 dirtied=615 written=29819
               ->  Index Scan using lineitem_l_orderkey_idx_part2 on lineitem  (cost=0.00..376148.39 rows=290493 width=15) (actual time=0.142..18411.508 rows=311082 loops=1)
                     Filter: ((l_shipmode = ANY ('{MAIL,AIR}'::bpchar[])) AND (l_receiptdate >= '1994-01-01'::date) AND (l_receiptdate < '1995-01-01 00:00:00'::timestamp without time zone))
                     Rows Removed by Filter: 6878925
                     Buffers: shared hit=196950 read=915542 dirtied=590 written=29744
               ->  Hash  (cost=404880.36..404880.36 rows=15059936 width=20) (actual time=16679.491..16679.491 rows=15000000 loops=1)
                     Buckets: 2097152  Batches: 1  Memory Usage: 761719kB
                     Buffers: shared hit=246500 read=7781 dirtied=25 written=75
                     ->  Seq Scan on orders  (cost=0.00..404880.36 rows=15059936 width=20) (actual time=0.018..6746.465 rows=15000000 loops=1)
                           Buffers: shared hit=246500 read=7781 dirtied=25 written=75
 Total runtime: 37212.359 ms
(19 rows)

COMMIT;
COMMIT