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

Sutou Kouhei <kou@clear-code.com>

From: Sutou Kouhei <kou@clear-code.com>
To: sawada.mshk@gmail.com
Cc: michael@paquier.xyz, zhjwpku@gmail.com, pgsql-hackers@postgresql.org
Date: 2025-02-28T03:57:09Z
Lists: pgsql-hackers
Hi,

In <CAD21AoDABLkUTTOwWa1he6gbc=nM46COMu-BvWjc_i6USnNbHw@mail.gmail.com>
  "Re: Make COPY format extendable: Extract COPY TO format implementations" on Thu, 27 Feb 2025 15:24:26 -0800,
  Masahiko Sawada <sawada.mshk@gmail.com> wrote:

> Pushed the 0001 patch.

Thanks!

> Regarding the 0002 patch, I realized we stopped exposing
> NextCopyFromRawFields() function:
> 
>  --- a/src/include/commands/copy.h
> +++ b/src/include/commands/copy.h
> @@ -107,8 +107,6 @@ extern CopyFromState BeginCopyFrom(ParseState
> *pstate, Relation rel, Node *where
>  extern void EndCopyFrom(CopyFromState cstate);
>  extern bool NextCopyFrom(CopyFromState cstate, ExprContext *econtext,
>                          Datum *values, bool *nulls);
> -extern bool NextCopyFromRawFields(CopyFromState cstate,
> -                                 char ***fields, int *nfields);
> 
> I think that this change is not relevant with the refactoring and
> probably we should keep it exposed as extension might be using it.
> Considering that we added pg_attribute_always_inline to the function,
> does it work even if we omit pg_attribute_always_inline to its
> function declaration in the copy.h file?

Unfortunately, no. The inline + constant argument
optimization requires "static".

How about the following?

static pg_attribute_always_inline bool
NextCopyFromRawFieldsInternal(CopyFromState cstate, char ***fields, int *nfields, bool is_csv)
{
    ...
}

bool
NextCopyFromRawFields(CopyFromState cstate, char ***fields, int *nfields)
{
    return NextCopyFromRawFieldsInternal(cstate, fields, nfields, cstate->opts.csv_mode);
}


Thanks,
-- 
kou



Commits

  1. Refactor Copy{From|To}GetRoutine() to use pass-by-reference argument.

  2. Refactor COPY FROM to use format callback functions.

  3. Refactor COPY TO to use format callback functions.

  4. Another try to fix BF failure introduced in commit ddd5f4f54a.

  5. Revert "Refactor CopyReadAttributes{CSV,Text}() to use a callback in COPY FROM"

  6. Improve COPY TO performance when server and client encodings match

  7. Simplify signature of CopyAttributeOutCSV() in copyto.c

  8. Revert "Refactor CopyAttributeOut{CSV,Text}() to use a callback in COPY TO"

  9. Refactor CopyAttributeOut{CSV,Text}() to use a callback in COPY TO

  10. Refactor CopyReadAttributes{CSV,Text}() to use a callback in COPY FROM

  11. Add progress reporting of skipped tuples during COPY FROM.

  12. pgbench: Add \syncpipeline

  13. meson: Make gzip and tar optional

  14. Export the external file reader used in COPY FROM as APIs.