Re: Make COPY format extendable: Extract COPY TO format implementations

On Thu, Dec 21, 2023 at 6:35 PM Sutou Kouhei <kou@clear-code.com> wrote:
>
> Hi,
>
> In <CAD21AoCunywHird3GaPzWe6s9JG1wzxj3Cr6vGN36DDheGjOjA@mail.gmail.com>
>   "Re: Make COPY format extendable: Extract COPY TO format implementations" on Mon, 11 Dec 2023 23:31:29 +0900,
>   Masahiko Sawada <sawada.mshk@gmail.com> wrote:
>
> > I've sketched the above idea including a test module in
> > src/test/module/test_copy_format, based on v2 patch. It's not splitted
> > and is dirty so just for discussion.
>
> I implemented a sample COPY TO handler for Apache Arrow that
> supports only integer and text.
>
> I needed to extend the patch:
>
> 1. Add an opaque space for custom COPY TO handler
>    * Add CopyToState{Get,Set}Opaque()
>    https://github.com/kou/postgres/commit/5a610b6a066243f971e029432db67152cfe5e944
>
> 2. Export CopyToState::attnumlist
>    * Add CopyToStateGetAttNumList()
>    https://github.com/kou/postgres/commit/15fcba8b4e95afa86edb3f677a7bdb1acb1e7688

I think we can move CopyToState to copy.h and we don't need to have
set/get functions for its fields.

Regards,

--
Masahiko Sawada
Amazon Web Services: https://aws.amazon.com