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 ('RAIL', '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=989412.00..989412.01 rows=1 width=27) (actual time=26573.049..26573.049 rows=2 loops=1)
   Sort Key: lineitem.l_shipmode
   Sort Method: quicksort  Memory: 25kB
   Buffers: shared hit=653230 read=713521 dirtied=498 written=19624
   ->  HashAggregate  (cost=989411.98..989411.99 rows=1 width=27) (actual time=26572.984..26572.985 rows=2 loops=1)
         Group Key: lineitem.l_shipmode
         Buffers: shared hit=653225 read=713521 dirtied=498 written=19624
         ->  Hash Join  (cost=596675.51..984287.90 rows=292805 width=27) (actual time=13423.625..26264.996 rows=312907 loops=1)
               Hash Cond: (lineitem.l_orderkey = orders.o_orderkey)
               Buffers: shared hit=653225 read=713521 dirtied=498 written=19624
               ->  Index Scan using lineitem_l_orderkey_idx_part2 on lineitem  (cost=0.43..378462.66 rows=292805 width=15) (actual time=0.229..12350.749 rows=312907 loops=1)
                     Filter: ((l_shipmode = ANY ('{RAIL,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: 6883655
                     Buffers: shared hit=485876 read=625066 dirtied=498 written=19317
               ->  Hash  (cost=407300.59..407300.59 rows=15149959 width=20) (actual time=13149.780..13149.780 rows=15015000 loops=1)
                     Buckets: 16777216  Batches: 1  Memory Usage: 893553kB
                     Buffers: shared hit=167346 read=88455 written=307
                     ->  Seq Scan on orders  (cost=0.00..407300.59 rows=15149959 width=20) (actual time=0.021..5747.440 rows=15015000 loops=1)
                           Buffers: shared hit=167346 read=88455 written=307
 Planning time: 2.975 ms
 Execution time: 26603.095 ms
(21 rows)

COMMIT;
COMMIT