Re: COPY TO (FREEZE)?

Hi,

On Tue, Aug 02, 2022 at 01:30:46PM +0900, Kyotaro Horiguchi wrote:
> I noticed that COPY TO accepts FREEZE option but it is pointless.
>
> Don't we reject that option as the first-attached does?

I agree that we should reject it, +1 for the patch.

> By the way, most of the invalid option combinations for COPY are
> marked as ERRCODE_FEATURE_NOT_SUPPORTED. I looks to me saying that
> "that feature is theoretically possible or actually realized
> elsewhere, but impossible now or here".
>
> If it is correct, aren't they better be ERRCODE_INVALID_PARAMETER_VALUE? The
> code is being used for similar messages "unrecognized parameter <name>" and
> "parameter <name> specified more than once" (or some others?). At least a
> quote string longer than a single character seems like to fit
> INVALID_PARAMETER_VALUE. (I believe we don't mean to support multicharacter
> (or even multibyte) escape/quote character anddelimiter). That being said,
> I'm not sure if the change will be worth the trouble.

I also feel weird about it. I raised the same point recently about COPY FROM +
HEADER MATCH (1), and at that time there wasn't a real consensus on the way to
go, just keep the things consistent. I'm +0.5 on that patch for the same
reason as back then. My only concern is that it can in theory break things if
you rely on the current sqlstate, but given the errors I don't think it's
really a problem.

[1]: https://www.postgresql.org/message-id/flat/20220614091319.jk4he5migtpwyd7r%40jrouhaud#b18bf3705fb9f69d0112b6febf0fa1be