From: Tom Lane <tgl@sss.pgh.pa.us>
To: Adrian Klaver <adrian.klaver@aklaver.com>
cc: Dimitrios Apostolou <jimis@gmx.net>, pgsql-general@lists.postgresql.org
Subject: Re: In-order pg_dump (or in-order COPY TO)
In-reply-to: <d6390ed7-771d-4ebb-bea1-749883b25d00@aklaver.com>
References: <s0491qrn-343s-0757-8sn5-120rr8610qqq@tzk.arg> <daf47435-539f-4368-869c-dd19a341399b@aklaver.com> <3541781s-75o7-26pp-46pp-qs54o4406192@tzk.arg> <c8d89b11-bada-4f23-9ff4-a8ed966f81a2@aklaver.com> <4ss66r31-558o-qq24-332q-no351p7n5osr@tzk.arg> <0dc17a73-2372-4613-a50e-610ae7d02b93@aklaver.com> <E48B611D-7D61-4575-A820-B2C3EC2E0551@gmx.net> <ccf26ec1-4fdf-496f-b222-de700071bdc1@aklaver.com> <84F8AAF7-8FC6-463C-827F-5D09E24EA911@gmx.net> <d6390ed7-771d-4ebb-bea1-749883b25d00@aklaver.com>
Comments: In-reply-to Adrian Klaver <adrian.klaver@aklaver.com>
	message dated "Mon, 01 Sep 2025 10:24:15 -0700"
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Date: Mon, 01 Sep 2025 13:54:16 -0400
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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.

			regards, tom lane