Re: Make stream_prepare an optional callback

On 09.03.21 09:39, Amit Kapila wrote:
> It is attached with the initial email.

Oh, sorry, I looked up the initial email, but still didn't see the patch.

> I think so. The behavior has to be similar to other optional callbacks
> like message_cb, truncate_cb, stream_truncate_cb. Basically, we don't
> need to error out if those callbacks are not provided.

Right, but the patch proposes to error out. I wonder whether that could
be avoided.

> The extension can request two_phase without streaming.

Sure. I'm worried about the case both are requested, but filter_prepare
returns false, i.e. asking for a streamed prepare without providing the
corresponding callback.

I wonder whether Postgres could deny the stream_prepare right away and
not even invoke filter_prepare. And instead just skip it because the
output plugin did not provide an appropriate callback.

An error is not as nice, but I'm okay with that as well.

Best Regards

Markus