Re: Add MIN/MAX aggregate support for uuid

On Tue Jun 23, 2026 at 6:04 PM UTC, Tristan Partin wrote:
> I noticed that we support various comparison operators on uuid values.
> However, we were missing support for the MIN and MAX aggregate
> functions, which seems like a logical thing to also support if we
> support operators.
>
> The use case that I envision the most is finding the oldest and newest
> UUID v7 values in a set. UUID v7 is a timestamp-prefixed identifier.
> According to RFC 9562[0], the first 48 bits of a UUID v7 value are
> a Unix Epoch timestamp. Additionally, Postgres implements Method 3 of
> Section 6.2[1] for UUID v7 such that the next 12 bits bits store a
> 1/4096 (or 2^12) fraction of sub-millisecond precision. See the comment
> in generate_uuidv7() for more details.
>
> [0]: https://datatracker.ietf.org/doc/html/rfc9562#name-uuid-version-7
> [1]: https://datatracker.ietf.org/doc/html/rfc9562#monotonicity_counters

And of course no patch attached :(.

--
Tristan Partin
PostgreSQL Contributors Team
AWS (https://aws.amazon.com)