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 ('FOB', '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=988852.98..988852.99 rows=1 width=27) (actual time=30613.821..30613.821 rows=2 loops=1)
   Sort Key: lineitem.l_shipmode
   Sort Method: quicksort  Memory: 25kB
   Buffers: shared hit=1229067 read=133227 written=3984
   ->  HashAggregate  (cost=988852.96..988852.97 rows=1 width=27) (actual time=30613.737..30613.738 rows=2 loops=1)
         Group Key: lineitem.l_shipmode
         Buffers: shared hit=1229062 read=133227 written=3984
         ->  Hash Join  (cost=596675.51..983771.84 rows=290350 width=27) (actual time=17165.377..30172.389 rows=312034 loops=1)
               Hash Cond: (lineitem.l_orderkey = orders.o_orderkey)
               Buffers: shared hit=1229062 read=133227 written=3984
               ->  Index Scan using lineitem_l_orderkey_idx_part2 on lineitem  (cost=0.43..378023.32 rows=290350 width=15) (actual time=0.132..12290.701 rows=312034 loops=1)
                     Filter: ((l_shipmode = ANY ('{FOB,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: 6884528
                     Buffers: shared hit=1051376 read=55109 written=3821
               ->  Hash  (cost=407300.59..407300.59 rows=15149959 width=20) (actual time=16727.301..16727.301 rows=15015000 loops=1)
                     Buckets: 16777216  Batches: 1  Memory Usage: 893553kB
                     Buffers: shared hit=177683 read=78118 written=163
                     ->  Seq Scan on orders  (cost=0.00..407300.59 rows=15149959 width=20) (actual time=0.028..6951.082 rows=15015000 loops=1)
                           Buffers: shared hit=177683 read=78118 written=163
 Planning time: 4.616 ms
 Execution time: 30653.294 ms
(21 rows)

COMMIT;
COMMIT