| From: | Karsten Hilbert <Karsten(dot)Hilbert(at)gmx(dot)net> |
|---|---|
| To: | Ruslan Zakirov <ruslan(dot)zakirov(at)gmail(dot)com> |
| Cc: | pgsql-general(at)lists(dot)postgresql(dot)org |
| Subject: | Re: Reproducing incorrect order with order by in a subquery |
| Date: | 2023-06-15 18:15:46 |
| Message-ID: | ZItVUvAFtq75Ts7o@hermes.hilbert.loc |
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| Lists: | pgsql-general |
Am Thu, Jun 15, 2023 at 12:58:55AM +0300 schrieb Ruslan Zakirov:
e.g.
> https://mariadb.com/kb/en/why-is-order-by-in-a-from-subquery-ignored/
...
> My goal was to find a small dataset that demonstrates this ordering
> mismatch.
I attempted to think it through whether it is even *possible*
to find a dataset (of any size) which *reliably* demonstrates
the ordering mismatch.
To my understanding -- since the outer query *can* (per
happenstance) return rows in the order of the subquery's
ORDER BY it is not possible to reliably demonstrate that it
won't, is it ?
Karsten
--
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