Re: UUID v7 - Mailing list pgsql-hackers

From Andrey M. Borodin
Subject Re: UUID v7
Date
Msg-id 3D3C3CFB-A689-47F0-968E-E136D6B126CF@yandex-team.ru
Whole thread Raw
In response to Re: UUID v7  (Masahiko Sawada <sawada.mshk@gmail.com>)
Responses Re: UUID v7
List pgsql-hackers

> On 1 Nov 2024, at 03:00, Masahiko Sawada <sawada.mshk@gmail.com> wrote:
>
> Therefore, if the
> system clock moves backward due to NTP, we cannot guarantee
> monotonicity and sortability. Is that right?

Not exactly. Monotonicity is ensured for a given backend. We make sure that timestamp is advanced at least for ~250ns
forwardon each UUID generation. 60 bits of time are unique and ascending for a given backend. 

Thanks!


Best regards, Andrey Borodin.


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