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', 'AIR')
	and l_commitdate < l_receiptdate
	and l_shipdate < l_commitdate
	and l_receiptdate >= date '1993-01-01'
	and l_receiptdate < date '1993-01-01' + interval '1 year'
group by
	l_shipmode
order by
	l_shipmode;
                                                                                          QUERY PLAN                                                                                          
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 Sort  (cost=991664.45..991664.45 rows=1 width=27) (actual time=39607.620..39607.621 rows=2 loops=1)
   Sort Key: lineitem.l_shipmode
   Sort Method: quicksort  Memory: 25kB
   Buffers: shared hit=679390 read=690396 dirtied=864 written=217
   ->  HashAggregate  (cost=991664.43..991664.44 rows=1 width=27) (actual time=39607.473..39607.473 rows=2 loops=1)
         Buffers: shared hit=679385 read=690396 dirtied=864 written=217
         ->  Hash Join  (cost=597855.36..986527.86 rows=293518 width=27) (actual time=16614.867..38995.596 rows=312975 loops=1)
               Hash Cond: (lineitem.l_orderkey = orders.o_orderkey)
               Buffers: shared hit=679385 read=690396 dirtied=864 written=217
               ->  Index Scan using lineitem_l_orderkey_idx_part2 on lineitem  (cost=0.00..379500.07 rows=293518 width=15) (actual time=1.334..21003.555 rows=312975 loops=1)
                     Filter: ((l_shipmode = ANY ('{RAIL,AIR}'::bpchar[])) AND (l_receiptdate >= '1993-01-01'::date) AND (l_receiptdate < '1994-01-01 00:00:00'::timestamp without time zone))
                     Rows Removed by Filter: 6883551
                     Buffers: shared hit=423384 read=690087 dirtied=112 written=216
               ->  Hash  (cost=408106.27..408106.27 rows=15179927 width=20) (actual time=16603.061..16603.061 rows=15015000 loops=1)
                     Buckets: 2097152  Batches: 1  Memory Usage: 762481kB
                     Buffers: shared hit=255998 read=309 dirtied=752 written=1
                     ->  Seq Scan on orders  (cost=0.00..408106.27 rows=15179927 width=20) (actual time=0.023..7639.027 rows=15015000 loops=1)
                           Buffers: shared hit=255998 read=309 dirtied=752 written=1
 Total runtime: 39826.620 ms
(19 rows)

COMMIT;
COMMIT