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', 'SHIP')
	and l_commitdate < l_receiptdate
	and l_shipdate < l_commitdate
	and l_receiptdate >= date '1995-01-01'
	and l_receiptdate < date '1995-01-01' + interval '1 year'
group by
	l_shipmode
order by
	l_shipmode;
                                                                                          QUERY PLAN                                                                                           
-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 Sort  (cost=983881.61..983881.61 rows=1 width=27) (actual time=36817.505..36817.505 rows=2 loops=1)
   Sort Key: lineitem.l_shipmode
   Sort Method: quicksort  Memory: 25kB
   Buffers: shared hit=699285 read=664078 dirtied=1072 written=52982
   ->  HashAggregate  (cost=983881.59..983881.60 rows=1 width=27) (actual time=36817.391..36817.393 rows=2 loops=1)
         Buffers: shared hit=699280 read=664078 dirtied=1072 written=52982
         ->  Hash Join  (cost=593129.56..978775.58 rows=291772 width=27) (actual time=15489.899..36241.261 rows=311273 loops=1)
               Hash Cond: (lineitem.l_orderkey = orders.o_orderkey)
               Buffers: shared hit=699280 read=664078 dirtied=1072 written=52982
               ->  Index Scan using lineitem_l_orderkey_idx_part2 on lineitem  (cost=0.00..376528.14 rows=291772 width=15) (actual time=0.286..19449.070 rows=311273 loops=1)
                     Filter: ((l_shipmode = ANY ('{RAIL,SHIP}'::bpchar[])) AND (l_receiptdate >= '1995-01-01'::date) AND (l_receiptdate < '1996-01-01 00:00:00'::timestamp without time zone))
                     Rows Removed by Filter: 6885910
                     Buffers: shared hit=458496 read=650578 dirtied=1072 written=52982
               ->  Hash  (cost=404880.36..404880.36 rows=15059936 width=20) (actual time=15475.254..15475.254 rows=15015000 loops=1)
                     Buckets: 2097152  Batches: 1  Memory Usage: 762481kB
                     Buffers: shared hit=240781 read=13500
                     ->  Seq Scan on orders  (cost=0.00..404880.36 rows=15059936 width=20) (actual time=0.014..6790.722 rows=15015000 loops=1)
                           Buffers: shared hit=240781 read=13500
 Total runtime: 36963.268 ms
(19 rows)

COMMIT;
COMMIT