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', 'TRUCK')
	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=984884.72..984884.72 rows=1 width=27) (actual time=36597.199..36597.199 rows=2 loops=1)
   Sort Key: lineitem.l_shipmode
   Sort Method: quicksort  Memory: 25kB
   Buffers: shared hit=992088 read=371376 written=2941
   ->  HashAggregate  (cost=984884.70..984884.71 rows=1 width=27) (actual time=36597.070..36597.070 rows=2 loops=1)
         Buffers: shared hit=992083 read=371376 written=2941
         ->  Hash Join  (cost=593719.70..979807.27 rows=290139 width=27) (actual time=16850.626..35995.319 rows=312336 loops=1)
               Hash Cond: (lineitem.l_orderkey = orders.o_orderkey)
               Buffers: shared hit=992083 read=371376 written=2941
               ->  Index Scan using lineitem_l_orderkey_idx_part2 on lineitem  (cost=0.00..377020.72 rows=290139 width=15) (actual time=0.174..17660.570 rows=312336 loops=1)
                     Filter: ((l_shipmode = ANY ('{MAIL,TRUCK}'::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: 6877529
                     Buffers: shared hit=773233 read=335689 written=590
               ->  Hash  (cost=405283.20..405283.20 rows=15074920 width=20) (actual time=16833.360..16833.360 rows=15000000 loops=1)
                     Buckets: 2097152  Batches: 1  Memory Usage: 761719kB
                     Buffers: shared hit=218847 read=35687 written=2351
                     ->  Seq Scan on orders  (cost=0.00..405283.20 rows=15074920 width=20) (actual time=0.028..8187.329 rows=15000000 loops=1)
                           Buffers: shared hit=218847 read=35687 written=2351
 Total runtime: 36747.660 ms
(19 rows)

COMMIT;
COMMIT