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', 'MAIL')
	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=994505.98..994505.98 rows=1 width=27) (actual time=26684.425..26684.425 rows=2 loops=1)
   Sort Key: lineitem.l_shipmode
   Sort Method: quicksort  Memory: 25kB
   Buffers: shared hit=1190653 read=177240 written=6433
   ->  HashAggregate  (cost=994505.96..994505.97 rows=1 width=27) (actual time=26684.304..26684.305 rows=2 loops=1)
         Buffers: shared hit=1190648 read=177240 written=6433
         ->  Hash Join  (cost=599625.78..989333.31 rows=295580 width=27) (actual time=13368.615..26293.104 rows=312574 loops=1)
               Hash Cond: (lineitem.l_orderkey = orders.o_orderkey)
               Buffers: shared hit=1190648 read=177240 written=6433
               ->  Index Scan using lineitem_l_orderkey_idx_part2 on lineitem  (cost=0.00..380470.65 rows=295580 width=15) (actual time=0.633..11870.379 rows=312574 loops=1)
                     Filter: ((l_shipmode = ANY ('{RAIL,MAIL}'::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: 6884151
                     Buffers: shared hit=949171 read=161648 written=6433
               ->  Hash  (cost=409314.79..409314.79 rows=15224879 width=20) (actual time=13351.591..13351.591 rows=15015000 loops=1)
                     Buckets: 2097152  Batches: 1  Memory Usage: 762481kB
                     Buffers: shared hit=241474 read=15592
                     ->  Seq Scan on orders  (cost=0.00..409314.79 rows=15224879 width=20) (actual time=0.018..6511.755 rows=15015000 loops=1)
                           Buffers: shared hit=241474 read=15592
 Total runtime: 26789.168 ms
(19 rows)

COMMIT;
COMMIT