Re: Transactions involving multiple postgres foreign servers, take 2 - Mailing list pgsql-hackers

From Fujii Masao
Subject Re: Transactions involving multiple postgres foreign servers, take 2
Date
Msg-id 45841cea-d757-b290-2a11-a81e06c8de9a@oss.nttdata.com
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In response to Re: Transactions involving multiple postgres foreign servers, take 2  (Masahiko Sawada <sawada.mshk@gmail.com>)
Responses Re: Transactions involving multiple postgres foreign servers, take 2  (Masahiko Sawada <sawada.mshk@gmail.com>)
List pgsql-hackers

On 2021/06/30 10:05, Masahiko Sawada wrote:
> I've attached the new version patch that incorporates the comments
> from Fujii-san and Ikeda-san I got so far.

Thanks for updating the patches!

I'm now reading 0001 and 0002 patches and wondering if we can commit them
at first because they just provide independent basic mechanism for
foreign transaction management.

One question regarding them is; Why did we add new API only for "top" foreign
transaction? Even with those patches, old API (CallSubXactCallbacks) is still
being used for foreign subtransaction and xact_depth is still being managed
in postgres_fdw layer (not PostgreSQL core). Is this intentional?
Sorry if this was already discussed before.

As far as I read the code, keep using old API for foreign subtransaction doesn't
cause any actual bug. But it's just strange and half-baked to manage top and
sub transaction in the differenet layer and to use old and new API for them.

OTOH, I'm afraid that adding new (not-essential) API for foreign subtransaction
might increase the code complexity unnecessarily.

Thought?

Regards,

-- 
Fujii Masao
Advanced Computing Technology Center
Research and Development Headquarters
NTT DATA CORPORATION



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