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 ('MAIL', 'REG AIR')
	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=986977.44..986977.44 rows=1 width=27) (actual time=26848.295..26848.296 rows=2 loops=1)
   Sort Key: lineitem.l_shipmode
   Sort Method: quicksort  Memory: 25kB
   Buffers: shared hit=850192 read=514338 written=517
   ->  HashAggregate  (cost=986977.42..986977.43 rows=1 width=27) (actual time=26848.208..26848.210 rows=2 loops=1)
         Group Key: lineitem.l_shipmode
         Buffers: shared hit=850187 read=514338 written=517
         ->  Hash Join  (cost=595495.23..981876.61 rows=291475 width=27) (actual time=10736.319..26461.373 rows=312515 loops=1)
               Hash Cond: (lineitem.l_orderkey = orders.o_orderkey)
               Buffers: shared hit=850187 read=514338 written=517
               ->  Index Scan using lineitem_l_orderkey_idx_part2 on lineitem  (cost=0.43..377273.21 rows=291475 width=15) (actual time=0.325..15154.461 rows=312515 loops=1)
                     Filter: ((l_shipmode = ANY ('{MAIL,"REG AIR"}'::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: 6884244
                     Buffers: shared hit=653015 read=456212 written=444
               ->  Hash  (cost=406494.91..406494.91 rows=15119991 width=20) (actual time=10633.195..10633.195 rows=15015000 loops=1)
                     Buckets: 16777216  Batches: 1  Memory Usage: 893553kB
                     Buffers: shared hit=197169 read=58126 written=73
                     ->  Seq Scan on orders  (cost=0.00..406494.91 rows=15119991 width=20) (actual time=0.028..5708.182 rows=15015000 loops=1)
                           Buffers: shared hit=197169 read=58126 written=73
 Planning time: 4.482 ms
 Execution time: 26862.759 ms
(21 rows)

COMMIT;
COMMIT