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', 'RAIL')
	and l_commitdate < l_receiptdate
	and l_shipdate < l_commitdate
	and l_receiptdate >= date '1996-01-01'
	and l_receiptdate < date '1996-01-01' + interval '1 year'
group by
	l_shipmode
order by
	l_shipmode;
                                                                                          QUERY PLAN                                                                                          
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 Sort  (cost=994876.28..994876.29 rows=1 width=27) (actual time=64127.990..64127.991 rows=2 loops=1)
   Sort Key: lineitem.l_shipmode
   Sort Method: quicksort  Memory: 25kB
   Buffers: shared hit=1060001 read=311441 written=23
   ->  HashAggregate  (cost=994876.26..994876.27 rows=1 width=27) (actual time=64127.834..64127.836 rows=2 loops=1)
         Buffers: shared hit=1059996 read=311441 written=23
         ->  Hash Join  (cost=600218.27..989738.72 rows=293574 width=27) (actual time=31281.858..63443.108 rows=312777 loops=1)
               Hash Cond: (lineitem.l_orderkey = orders.o_orderkey)
               Buffers: shared hit=1059996 read=311441 written=23
               ->  Index Scan using lineitem_l_orderkey_idx_part2 on lineitem  (cost=0.00..380346.26 rows=293574 width=15) (actual time=6.840..30684.377 rows=312777 loops=1)
                     Filter: ((l_shipmode = ANY ('{AIR,RAIL}'::bpchar[])) AND (l_receiptdate >= '1996-01-01'::date) AND (l_receiptdate < '1997-01-01 00:00:00'::timestamp without time zone))
                     Rows Removed by Filter: 6883838
                     Buffers: shared hit=927656 read=186458 written=23
               ->  Hash  (cost=409719.23..409719.23 rows=15239923 width=20) (actual time=31255.211..31255.211 rows=15015000 loops=1)
                     Buckets: 2097152  Batches: 1  Memory Usage: 762481kB
                     Buffers: shared hit=132337 read=124983
                     ->  Seq Scan on orders  (cost=0.00..409719.23 rows=15239923 width=20) (actual time=0.030..21650.937 rows=15015000 loops=1)
                           Buffers: shared hit=132337 read=124983
 Total runtime: 64317.917 ms
(19 rows)

COMMIT;
COMMIT