Message-ID: <8aae908b-7e9d-4287-959d-18765f84c725@postgrespro.ru>
Date: Wed, 6 Mar 2024 09:26:49 +0700
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Subject: Re: Hooking into ExplainOneQuery() complicated by missing
 standard_ExplainOneQuery
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To: Michael Paquier <michael@paquier.xyz>, Mats Kindahl <mats@timescale.com>
Cc: Aleksander Alekseev <aleksander@timescale.com>,
 pgsql-hackers@lists.postgresql.org
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 <Zeep3F-uh8oDpuR3@paquier.xyz>
From: Andrei Lepikhov <a.lepikhov@postgrespro.ru>
Organization: Postgres Professional
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On 6/3/2024 06:25, Michael Paquier wrote:
>> Just to elaborate: the intention was to allow a section to be added to
>> every node in the plan containing information from further down and also
>> allow this information to propagate upwards. We happen to have buffer
>> information right now, but allowing something similar to be added
>> dynamically by extending ExplainNode and passing down a callback to
>> standard_ExplainOneQuery.
> 
> Or an extra hook at the end of ExplainNode() to be able to append more
> information at node level?  Not sure if others would agree with that,
> though.

We already discussed EXPLAIN hooks, at least in [1]. IMO, extensions 
should have a chance to add something to the node explain and the 
summary, if only because they can significantly influence the planner 
and executor's behaviour.

[1] 
https://www.postgresql.org/message-id/flat/6cd5caa7-06e1-4460-bf35-00a59da3f677%40garret.ru

-- 
regards,
Andrei Lepikhov
Postgres Professional