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 ('AIR', 'FOB')
	and l_commitdate < l_receiptdate
	and l_shipdate < l_commitdate
	and l_receiptdate >= date '1993-01-01'
	and l_receiptdate < date '1993-01-01' + interval '1 year'
group by
	l_shipmode
order by
	l_shipmode;
                                                                                         QUERY PLAN                                                                                          
---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 Sort  (cost=991871.16..991871.16 rows=1 width=27) (actual time=23371.054..23371.055 rows=2 loops=1)
   Sort Key: lineitem.l_shipmode
   Sort Method: quicksort  Memory: 25kB
   Buffers: shared hit=1011177 read=355308 written=391
   ->  HashAggregate  (cost=991871.14..991871.15 rows=1 width=27) (actual time=23370.984..23370.986 rows=2 loops=1)
         Group Key: lineitem.l_shipmode
         Buffers: shared hit=1011172 read=355308 written=391
         ->  Hash Join  (cost=598445.93..986746.40 rows=292842 width=27) (actual time=11482.928..23071.543 rows=312870 loops=1)
               Hash Cond: (lineitem.l_orderkey = orders.o_orderkey)
               Buffers: shared hit=1011172 read=355308 written=391
               ->  Index Scan using lineitem_l_orderkey_idx_part2 on lineitem  (cost=0.43..379149.59 rows=292842 width=15) (actual time=0.301..11186.616 rows=312870 loops=1)
                     Filter: ((l_shipmode = ANY ('{AIR,FOB}'::bpchar[])) AND (l_receiptdate >= '1993-01-01'::date) AND (l_receiptdate < '1994-01-01 00:00:00'::timestamp without time zone))
                     Rows Removed by Filter: 6883800
                     Buffers: shared hit=828991 read=280926 written=322
               ->  Hash  (cost=408509.11..408509.11 rows=15194911 width=20) (actual time=11389.165..11389.165 rows=15015000 loops=1)
                     Buckets: 16777216  Batches: 1  Memory Usage: 893553kB
                     Buffers: shared hit=182178 read=74382 written=69
                     ->  Seq Scan on orders  (cost=0.00..408509.11 rows=15194911 width=20) (actual time=0.023..6255.349 rows=15015000 loops=1)
                           Buffers: shared hit=182178 read=74382 written=69
 Planning time: 3.091 ms
 Execution time: 23382.562 ms
(21 rows)

COMMIT;
COMMIT