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', 'SHIP')
	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=990438.33..990438.34 rows=1 width=27) (actual time=50892.698..50892.699 rows=2 loops=1)
   Sort Key: lineitem.l_shipmode
   Sort Method: quicksort  Memory: 25kB
   Buffers: shared hit=1227544 read=150000 dirtied=178 written=6
   ->  HashAggregate  (cost=990438.31..990438.32 rows=1 width=27) (actual time=50892.564..50892.565 rows=2 loops=1)
         Buffers: shared hit=1227539 read=150000 dirtied=178 written=6
         ->  Hash Join  (cost=597265.22..985340.28 rows=291316 width=27) (actual time=21104.018..50242.950 rows=313314 loops=1)
               Hash Cond: (lineitem.l_orderkey = orders.o_orderkey)
               Buffers: shared hit=1227539 read=150000 dirtied=178 written=6
               ->  Index Scan using lineitem_l_orderkey_idx_part2 on lineitem  (cost=0.00..378971.44 rows=291316 width=15) (actual time=0.158..27881.422 rows=313314 loops=1)
                     Filter: ((l_shipmode = ANY ('{AIR,SHIP}'::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: 6883268
                     Buffers: shared hit=982593 read=138889 dirtied=148 written=6
               ->  Hash  (cost=407703.43..407703.43 rows=15164943 width=20) (actual time=21090.157..21090.157 rows=15015000 loops=1)
                     Buckets: 2097152  Batches: 1  Memory Usage: 762481kB
                     Buffers: shared hit=244943 read=11111 dirtied=30
                     ->  Seq Scan on orders  (cost=0.00..407703.43 rows=15164943 width=20) (actual time=0.027..11954.677 rows=15015000 loops=1)
                           Buffers: shared hit=244943 read=11111 dirtied=30
 Total runtime: 50983.804 ms
(19 rows)

COMMIT;
COMMIT