t;> select *
>> from information_schema.role_usage_grants f1
>> where grantor =
>> ( select max(ref_2.grantor)
>> from
>>information_schema.role_usage_grants as ref_2,
>>lateral (
>> select
>> max((null)
pg_catalog.pg_amop as ref_3
> ) as subq_0
> where ref_2.object_catalog = f1.object_catalog
> )
> ;
>
>
> CORRELATED querying time
> on old version(9.4/9.5): 0.6s
> on latest version(10): 113s
> 188 times slower
>
>
>
> -
ing time
on old version(9.4/9.5): 0.6s
on latest version(10): 113s
188 times slower
From: Tom Lane
Sent: Saturday, October 13, 2018 5:59:06 PM
To: Jung, Jinho
Cc: pgsql-hackers@lists.postgresql.org
Subject: Re: Regarding query minimizer (simplifier)
"Jung
"Jung, Jinho" writes:
> Hello, I am Jinho Jung, Phd Student from GeorgiaTech, and try to find any SQL
> queries that cause performance regression. While conducting evaluation, I
> found an interesting query which makes x80 times slower execution in version
> 10.5 than version 9.4. Please see th
Hello, I am Jinho Jung, Phd Student from GeorgiaTech, and try to find any SQL
queries that cause performance regression. While conducting evaluation, I found
an interesting query which makes x80 times slower execution in version 10.5
than version 9.4. Please see the attached files, if you are i
