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', 'TRUCK')
	and l_commitdate < l_receiptdate
	and l_shipdate < l_commitdate
	and l_receiptdate >= date '1996-01-01'
	and l_receiptdate < date '1996-01-01' + interval '1 year'
group by
	l_shipmode
order by
	l_shipmode;
                                                                                           QUERY PLAN                                                                                           
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 Sort  (cost=986219.40..986219.41 rows=1 width=27) (actual time=52030.502..52030.503 rows=2 loops=1)
   Sort Key: lineitem.l_shipmode
   Sort Method: quicksort  Memory: 25kB
   Buffers: shared hit=831910 read=536054 dirtied=980 written=7962
   ->  HashAggregate  (cost=986219.38..986219.39 rows=1 width=27) (actual time=52030.391..52030.392 rows=2 loops=1)
         Buffers: shared hit=831905 read=536054 dirtied=980 written=7962
         ->  Hash Join  (cost=594902.33..981083.20 rows=293496 width=27) (actual time=22079.282..51355.859 rows=312329 loops=1)
               Hash Cond: (lineitem.l_orderkey = orders.o_orderkey)
               Buffers: shared hit=831905 read=536054 dirtied=980 written=7962
               ->  Index Scan using lineitem_l_orderkey_idx_part2 on lineitem  (cost=0.00..377009.12 rows=293496 width=15) (actual time=2.679..27872.129 rows=312329 loops=1)
                     Filter: ((l_shipmode = ANY ('{MAIL,TRUCK}'::bpchar[])) AND (l_receiptdate >= '1996-01-01'::date) AND (l_receiptdate < '1997-01-01 00:00:00'::timestamp without time zone))
                     Rows Removed by Filter: 6877350
                     Buffers: shared hit=659764 read=453151 dirtied=795 written=5393
               ->  Hash  (cost=406090.48..406090.48 rows=15104948 width=20) (actual time=22054.790..22054.790 rows=15000000 loops=1)
                     Buckets: 2097152  Batches: 1  Memory Usage: 761719kB
                     Buffers: shared hit=172138 read=82903 dirtied=185 written=2569
                     ->  Seq Scan on orders  (cost=0.00..406090.48 rows=15104948 width=20) (actual time=0.016..11041.238 rows=15000000 loops=1)
                           Buffers: shared hit=172138 read=82903 dirtied=185 written=2569
 Total runtime: 52215.369 ms
(19 rows)

COMMIT;
COMMIT