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From: Nazir Bilal Yavuz <byavuz81@gmail.com>
Date: Wed, 19 Nov 2025 10:27:59 +0300
Message-ID: 
 <CAN55FZ0tgjF1beJSRXw3rgkbzwPZ7ngChJkPZm9aJkPuaF=dmg@mail.gmail.com>
Subject: Re: Trying out read streams in pgvector (an extension)
To: Melanie Plageman <melanieplageman@gmail.com>
Cc: Thomas Munro <thomas.munro@gmail.com>,
 "Jonathan S. Katz" <jkatz@postgresql.org>,
	pgsql-hackers <pgsql-hackers@postgresql.org>
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Hi,

On Wed, 19 Nov 2025 at 00:17, Melanie Plageman
<melanieplageman@gmail.com> wrote:
>
> To make sure 1) distance isn't reset to a resume_distance from
> read_stream_begin_relation() and 2) unexpected buffers aren't returned
> from the read stream, we could error out in read_stream_resume() if
> pinned_buffers > 0. And in read_stream_reset(), we would save distance
> in resume_distance before clearing distance. That would allow calling
> read_stream_resume() either if you called read_stream_reset() or if
> you exhausted the stream yourself. See rough attached patch for a
> sketch of this.

This looks correct to me. What do you think about using an assert
instead of erroring out?

-- 
Regards,
Nazir Bilal Yavuz
Microsoft