Re: Extend COPY FROM with HEADER to skip multiple lines

On 2025/06/10 9:43, Shinya Kato wrote:
>>> However, a similar proposal was made earlier [1], and seemingly
>>> some hackers weren't in favor of it. It's probably worth reading
>>> that thread to understand the previous concerns.
>>>
>>> [1] https://postgr.es/m/CALAY4q8nGSXp0P5uf56vn-mD7reWqZP5k6PS1CGUm26X4FsYJA@mail.gmail.com
>>
>> Oh, I missed it. I will check it soon.
> 
> I read it.
> 
> There are clear differences from the earlier proposal. My sole
> motivation is to skip multiple headers, and I don't believe a feature
> for skipping footers is necessary. To be clear, I think it's best to
> simply extend the current HEADER option.

Sounds ok to me.


> Regarding the concern about adding ETL-like functionality, this
> feature is already implemented in other RDBMSs, which is why I believe
> it is also necessary for PostgreSQL.
> 
> Honestly, I haven't implemented it yet, so I'm not sure about the
> performance. However, I don't expect it to be significantly different
> from the current HEADER option that skips a single line.

So it seems better for you to implement the patch at first and then
check the performance overhead etc if necessary.

Regards,

-- 
Fujii Masao
NTT DATA Japan Corporation