Hi all,
Please see this case.
TPC-DS query 95:
with ws_wh as
(select ws1.ws_order_number,ws1.ws_warehouse_sk wh1,ws2.ws_warehouse_sk wh2
from web_sales ws1,web_sales ws2
where ws1.ws_order_number = ws2.ws_order_number
and ws1.ws_warehouse_sk <> ws2.ws_warehouse_sk)
select
count(distinct
Hi all,
Still for the query 95:
with ws_wh as
(select ws1.ws_order_number,ws1.ws_warehouse_sk wh1,ws2.ws_warehouse_sk wh2
from web_sales ws1,web_sales ws2
where ws1.ws_order_number = ws2.ws_order_number
and ws1.ws_warehouse_sk <> ws2.ws_warehouse_sk)
select
count(distinct ws_order_number
>> The default configurations of PostgreSQL incur the error: "ERROR: could not
>> resize shared memory segment "/PostgreSQL.3539600020" to 2097152 bytes: No
>> space left on device"
>No comment on your optimiser experiments for now, but for this error:
>it reminds me of a low/default --shm-siz
>It is all the time a challenge for PostgreSQL to estimate such a filter
>because of absent information on joint column distribution.
>Can you research this way by building extended statistics on these
>clauses? It could move the plan to the more optimal direction.
Thanks a lot for your effort to
Please see this case:
TPC-H query 2:
select
s_acctbal,
s_name,
n_name,
p_partkey,
p_mfgr,
s_address,
s_phone,
s_comment
from
PART,
SUPPLIER,
PARTSUPP,
NATION,
REGION
where
p_partkey = ps_partkey
and s_suppkey = ps_suppkey
and p_size
sheng Ba
From: Tom Lane
Sent: Saturday, October 26, 2024 8:28 AM
To: Ba Jinsheng
Cc: pgsql-performance@lists.postgresql.org
Subject: Re: Unexpected Performance for the Function simplify_function
- External Email -
Ba Jinsheng writes:
>> It looks like the better p
>It looks like the better plan involves a
>nestloop with inner indexscan on lineitem, which is something whose
>estimated cost depends enormously on random_page_cost. You've given
>us exactly zero detail about your test conditions, so it's hard to say
>more than that.
I used the default configura
Jinsheng Ba
From: Andrei Lepikhov
Sent: Friday, October 25, 2024 4:13 AM
To: Ba Jinsheng
Cc: pgsql-performance@lists.postgresql.org
Subject: Re: Unexpected Performance for the Function simplify_function
- External Email -
On 10/25/24 02:43, Ba
Dear PostgreSQL Community,
For the query 10 in TPC-H benchmark:
select
c_custkey,
c_name,
sum(l_extendedprice * (1 - l_discount)) as revenue,
c_acctbal,
n_name,
c_address,
c_phone,
c_comment
from
CUSTOMER,
ORDERS,
LINEITEM,
NA
