public inbox for [email protected]
help / color / mirror / Atom feedFrom: Robert Haas <[email protected]>
To: Etsuro Fujita <[email protected]>
Cc: Tom Lane <[email protected]>
Cc: Andres Freund <[email protected]>
Cc: Ashutosh Bapat <[email protected]>
Cc: Rajkumar Raghuwanshi <[email protected]>
Cc: pgsql-hackers <[email protected]>
Subject: Re: Expression errors with "FOR UPDATE" and postgres_fdw with partition wise join enabled.
Date: Tue, 14 Aug 2018 15:51:10 +0000
Message-ID: <CA+TgmoaNuWR-Krw9L2NOARNd7gJfHXwgOO8=8J4YAp+P4a1djA@mail.gmail.com> (raw)
In-Reply-To: <[email protected]>
References: <[email protected]>
<CA+TgmoZboTszGQk3OecBOZUFNNjzKE-SOo_Q46xtTJ4Yj95-RQ@mail.gmail.com>
<[email protected]>
<[email protected]>
<[email protected]>
<CA+TgmobR9XWEhmF3s_WsoLNnnjaFyS_xtbrVG3dCGiUgof20Nw@mail.gmail.com>
<CA+TgmoZSaKq-fYALn5jf6c_X3==Rb2s8eqLDwGpV=LNNhTXYwg@mail.gmail.com>
<[email protected]>
<CA+TgmoYYTCQL=TUYbUz2b=CsQeB4o1L2+_=zHynxGVmyKUtH1A@mail.gmail.com>
<[email protected]>
<CA+TgmoazFzdp5ZVwUjk_b2cuB90WCeeWtzt1ShSbXGyg67c+Zw@mail.gmail.com>
<[email protected]>
<[email protected]>
<CA+TgmoZMdNiKUGV0=-QLV1f1-Xr0CDT+8y9wLktuEiQGkt64UQ@mail.gmail.com>
<CA+TgmoZjYHtkw-o_4=-GXb6obF1epyivr+WnZ1SQCnU6fgtf+w@mail.gmail.com>
<[email protected]>
<[email protected]>
<[email protected]>
<[email protected]>
<CA+TgmoYhgEkcR1E-BMS-2G8A4_5z0bbN6vCO+uR7HyQCOsWpEw@mail.gmail.com>
<[email protected]>
On Mon, Aug 13, 2018 at 12:32 PM, Etsuro Fujita
<[email protected]> wrote:
> One thing I noticed might be an improvement is to skip
> build_joinrel_partition_info if the given joinrel will be to have
> consider_partitionwise_join=false; in the previous patch, that function
> created the joinrel's partition info such as part_scheme and part_rels if
> the joinrel is considered as partitioned, independently of the flag
> consider_partitionwise_join for it, but if that flag is false, we don't
> generate PWJ paths for the joinrel, so we would not need to create that
> partition info at all. This would not only avoid unnecessary processing in
> that function, but also make unnecessary the changes I made to
> try_partitionwise_join, generate_partitionwise_join_paths,
> apply_scanjoin_target_to_paths, and create_ordinary_grouping_paths. So I
> updated the patch that way. Please find attached an updated version of the
> patch.
I guess the question is whether there are (or might be in the future)
other dependencies on part_scheme. For example, it looks like
partition pruning uses it. I'm not sure whether partition pruning
supports a plan like:
Append
-> Nested Loop
-> Seq Scan on p1
-> Index Scan on q1
<repeat the above for p2/q2 etc.>
If it doesn't, that's just an implementation restriction; somebody
might want to fix things so it works, if it doesn't already.
--
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company
view thread (115+ messages) latest in thread
reply
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Reply to all the recipients using the --to and --cc options:
reply via email
To: [email protected]
Cc: [email protected], [email protected], [email protected], [email protected], [email protected], [email protected]
Subject: Re: Expression errors with "FOR UPDATE" and postgres_fdw with partition wise join enabled.
In-Reply-To: <CA+TgmoaNuWR-Krw9L2NOARNd7gJfHXwgOO8=8J4YAp+P4a1djA@mail.gmail.com>
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
This inbox is served by agora; see mirroring instructions
for how to clone and mirror all data and code used for this inbox