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From: Daniele Varrazzo <daniele.varrazzo@gmail.com>
Date: Tue, 10 Nov 2020 03:30:47 +0000
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Subject: Re: psycopg3 and adaptation choices
To: Christophe Pettus <xof@thebuild.com>
Cc: psycopg@postgresql.org
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On Tue, 10 Nov 2020 at 03:20, Christophe Pettus <xof@thebuild.com> wrote:
>
> I don't want to derail this, but a question: Can a connection be set to use the simple-query protocol instead of the extended-query protocol in 3?

It won't be set explicitly to use simple/extended protocol, but if a
query is passed with no parameter (because it just has no variable
part, or because it's being composed client-side using functionalities
similar to psycopg2.sql) then the simple-query protocol is used [1].
This is mostly useful to pass several queries at once, because the
extended query protocol doesn't allow more than one query at time [2].

[1] https://github.com/psycopg/psycopg3/blob/bc02ae1c9c42892966ff079250c24ff5eae28b48/psycopg3/psycopg3/cursor.py#L243-L254
[2] https://www.postgresql.org/docs/current/libpq-exec.html#LIBPQ-PQEXECPARAMS

-- Daniele