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 ('SHIP', 'MAIL')
	and l_commitdate < l_receiptdate
	and l_shipdate < l_commitdate
	and l_receiptdate >= date '1997-01-01'
	and l_receiptdate < date '1997-01-01' + interval '1 year'
group by
	l_shipmode
order by
	l_shipmode;
                                                                                          QUERY PLAN                                                                                           
-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 Sort  (cost=990896.26..990896.26 rows=1 width=27) (actual time=43787.195..43787.196 rows=2 loops=1)
   Sort Key: lineitem.l_shipmode
   Sort Method: quicksort  Memory: 25kB
   Buffers: shared hit=605063 read=764723 dirtied=253 written=271
   ->  HashAggregate  (cost=990896.24..990896.25 rows=1 width=27) (actual time=43787.075..43787.076 rows=2 loops=1)
         Buffers: shared hit=605058 read=764723 dirtied=253 written=271
         ->  Hash Join  (cost=597855.36..985813.71 rows=290430 width=27) (actual time=16405.866..43182.265 rows=311536 loops=1)
               Hash Cond: (lineitem.l_orderkey = orders.o_orderkey)
               Buffers: shared hit=605058 read=764723 dirtied=253 written=271
               ->  Index Scan using lineitem_l_orderkey_idx_part2 on lineitem  (cost=0.00..378882.42 rows=290430 width=15) (actual time=0.209..25373.863 rows=311536 loops=1)
                     Filter: ((l_shipmode = ANY ('{SHIP,MAIL}'::bpchar[])) AND (l_receiptdate >= '1997-01-01'::date) AND (l_receiptdate < '1998-01-01 00:00:00'::timestamp without time zone))
                     Rows Removed by Filter: 6884990
                     Buffers: shared hit=349003 read=764468 written=271
               ->  Hash  (cost=408106.27..408106.27 rows=15179927 width=20) (actual time=16389.795..16389.795 rows=15015000 loops=1)
                     Buckets: 2097152  Batches: 1  Memory Usage: 762481kB
                     Buffers: shared hit=256052 read=255 dirtied=253
                     ->  Seq Scan on orders  (cost=0.00..408106.27 rows=15179927 width=20) (actual time=0.023..8036.049 rows=15015000 loops=1)
                           Buffers: shared hit=256052 read=255 dirtied=253
 Total runtime: 43962.686 ms
(19 rows)

COMMIT;
COMMIT