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', 'RAIL')
	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=990589.41..990589.42 rows=1 width=27) (actual time=52511.406..52511.406 rows=2 loops=1)
   Sort Key: lineitem.l_shipmode
   Sort Method: quicksort  Memory: 25kB
   Buffers: shared hit=1161735 read=210898 dirtied=300 written=96
   ->  HashAggregate  (cost=990589.39..990589.40 rows=1 width=27) (actual time=52511.247..52511.248 rows=2 loops=1)
         Buffers: shared hit=1161730 read=210898 dirtied=300 written=96
         ->  Hash Join  (cost=597265.22..985437.13 rows=294415 width=27) (actual time=22722.179..51870.744 rows=312558 loops=1)
               Hash Cond: (lineitem.l_orderkey = orders.o_orderkey)
               Buffers: shared hit=1161730 read=210898 dirtied=300 written=96
               ->  Index Scan using lineitem_l_orderkey_idx_part2 on lineitem  (cost=0.00..378971.44 rows=294415 width=15) (actual time=0.513..27927.613 rows=312558 loops=1)
                     Filter: ((l_shipmode = ANY ('{MAIL,RAIL}'::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: 6884024
                     Buffers: shared hit=969788 read=146783 dirtied=77 written=6
               ->  Hash  (cost=407703.43..407703.43 rows=15164943 width=20) (actual time=22711.063..22711.063 rows=15015000 loops=1)
                     Buckets: 2097152  Batches: 1  Memory Usage: 762481kB
                     Buffers: shared hit=191939 read=64115 dirtied=223 written=90
                     ->  Seq Scan on orders  (cost=0.00..407703.43 rows=15164943 width=20) (actual time=0.085..13680.963 rows=15015000 loops=1)
                           Buffers: shared hit=191939 read=64115 dirtied=223 written=90
 Total runtime: 52627.971 ms
(19 rows)

COMMIT;
COMMIT