Re: ON CONFLICT DO NOTHING on pg_dump

On Tue, Jun 12, 2018 at 09:05:23AM +0000, Ideriha, Takeshi wrote:
> >From: Surafel Temesgen [mailto:surafel3000(at)gmail(dot)com]
> >Subject: ON CONFLICT DO NOTHING on pg_dump
>
> >Sometimes I have to maintain two similar database and I have to update one from the other and notice having the option to add ON CONFLICT DO NOTHING clause to >INSERT command in the dump data will allows pg_restore to be done with free of ignore error.
>
> Hi,
> I feel like that on-conflict-do-nothing support is useful especially coupled with --data-only option.
> Only the difference of data can be restored.

But that's additive-only. Only missing rows are restored this way, and
differences are not addressed.

If you want restore to restore data properly and concurrently (as
opposed to renaming a new database into place or whatever) then you'd
want a) MERGE, b) dump to generate MERGE statements. A concurrent data
restore operation would be rather neat.

Nico
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