Dominique Devienne <ddevienne(at)gmail(dot)com> writes:
> For the first time, I'm checking the OIDs returned
> (via the result set's PQftype API), by "regular" SELECT:
> ...
> And to my surprise, they are not!
> The ones from the COPY are all zeros.
> Is that normal?
The CopyInResponse and CopyOutResponse messages don't carry any
column name or type indications, so yes it's normal.
https://www.postgresql.org/docs/current/protocol-message-formats.html
Maybe we missed a bet there, but AFAIR you are the first person to
ask for this in twenty-plus years.
regards, tom lane