Message-ID: <433d0845248e86c0317d9d396926182cfe157340.camel@j-davis.com>
Subject: Re: [17] CREATE SUBSCRIPTION ... SERVER
From: Jeff Davis <pgsql@j-davis.com>
To: Ashutosh Bapat <ashutosh.bapat.oss@gmail.com>, Joe Conway
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Cc: pgsql-hackers@postgresql.org
Date: Fri, 01 Sep 2023 11:54:44 -0700
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On Fri, 2023-09-01 at 12:28 +0530, Ashutosh Bapat wrote:
> Thinking larger, how about we allow any FDW to be used here.

That's a possibility, but I think that means the subscription would
need to constantly re-check the parameters rather than relying on the
FDW's validator.

Otherwise it might be the wrong kind of FDW, and the user might be able
to circumvent the password_required protection. It might not even be a
postgres-related FDW at all, which would be a bit strange.

If it's constantly re-checking the parameters then it raises the
possibility that some "ALTER SERVER" or "ALTER USER MAPPING" succeeds
but then subscriptions to that foreign server start failing, which
would not be ideal. But I could be fine with that.

> But I think there's some value in bringing
> together these two subsystems which deal with foreign data logically
> (as in logical vs physical view of data).

I still don't understand how a core dependency on an extension would
work.

Regards,
	Jeff Davis