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', 'AIR')
	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=984128.23..984128.23 rows=1 width=27) (actual time=78280.428..78280.428 rows=2 loops=1)
   Sort Key: lineitem.l_shipmode
   Sort Method: quicksort  Memory: 25kB
   Buffers: shared hit=1048619 read=318415 written=74
   ->  HashAggregate  (cost=984128.21..984128.22 rows=1 width=27) (actual time=78280.320..78280.320 rows=2 loops=1)
         Buffers: shared hit=1048614 read=318415 written=74
         ->  Hash Join  (cost=593719.70..979039.35 rows=290792 width=27) (actual time=23489.808..77489.818 rows=312831 loops=1)
               Hash Cond: (lineitem.l_orderkey = orders.o_orderkey)
               Buffers: shared hit=1048614 read=318415 written=74
               ->  Index Scan using lineitem_l_orderkey_idx_part2 on lineitem  (cost=0.00..376232.40 rows=290792 width=15) (actual time=0.331..52365.584 rows=312831 loops=1)
                     Filter: ((l_shipmode = ANY ('{MAIL,AIR}'::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: 6884371
                     Buffers: shared hit=795156 read=317336 written=73
               ->  Hash  (cost=405283.20..405283.20 rows=15074920 width=20) (actual time=23479.612..23479.612 rows=15015000 loops=1)
                     Buckets: 2097152  Batches: 1  Memory Usage: 762481kB
                     Buffers: shared hit=253455 read=1079 written=1
                     ->  Seq Scan on orders  (cost=0.00..405283.20 rows=15074920 width=20) (actual time=0.035..14448.996 rows=15015000 loops=1)
                           Buffers: shared hit=253455 read=1079 written=1
 Total runtime: 78449.850 ms
(19 rows)

COMMIT;
COMMIT