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 ('TRUCK', '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=994748.07..994748.08 rows=1 width=27) (actual time=37280.974..37280.974 rows=2 loops=1)
   Sort Key: lineitem.l_shipmode
   Sort Method: quicksort  Memory: 25kB
   Buffers: shared hit=862084 read=509358
   ->  HashAggregate  (cost=994748.05..994748.06 rows=1 width=27) (actual time=37280.819..37280.820 rows=2 loops=1)
         Buffers: shared hit=862079 read=509358
         ->  Hash Join  (cost=600218.27..989656.53 rows=290944 width=27) (actual time=21494.613..36832.809 rows=312574 loops=1)
               Hash Cond: (lineitem.l_orderkey = orders.o_orderkey)
               Buffers: shared hit=862079 read=509358
               ->  Index Scan using lineitem_l_orderkey_idx_part2 on lineitem  (cost=0.00..380346.26 rows=290944 width=15) (actual time=0.373..14212.213 rows=312574 loops=1)
                     Filter: ((l_shipmode = ANY ('{TRUCK,"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: 6884041
                     Buffers: shared hit=726144 read=387970
               ->  Hash  (cost=409719.23..409719.23 rows=15239923 width=20) (actual time=21481.654..21481.654 rows=15015000 loops=1)
                     Buckets: 2097152  Batches: 1  Memory Usage: 762481kB
                     Buffers: shared hit=135932 read=121388
                     ->  Seq Scan on orders  (cost=0.00..409719.23 rows=15239923 width=20) (actual time=0.029..13057.647 rows=15015000 loops=1)
                           Buffers: shared hit=135932 read=121388
 Total runtime: 37382.943 ms
(19 rows)

COMMIT;
COMMIT