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Date: Mon, 1 Sep 2025 12:02:15 -0700
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Subject: Re: In-order pg_dump (or in-order COPY TO)
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Dimitrios Apostolou <jimis@gmx.net>, pgsql-general@lists.postgresql.org
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From: Adrian Klaver <adrian.klaver@aklaver.com>
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On 9/1/25 10:54, Tom Lane wrote:
> Adrian Klaver <adrian.klaver@aklaver.com> writes:
>> I did some digging in the code and see that the TOC is more then that,
>> it stores a range of data. Still have not part where the offsets are
>> ignored for writes to stdout, but will keep on digging.
> 
> The TOC is initially written out with zeroes for the offsets.
> Then the per-table data parts are written out, tracking where
> each one begins.  At the end, if the output file is seekable,
> pg_dump seeks back to the start and re-writes the whole TOC
> section, now with data offsets populated.  But output to a
> pipe won't be seekable.

Got it, thanks.

> 
> 			regards, tom lane


-- 
Adrian Klaver
adrian.klaver@aklaver.com