Comment by NyxWulf
13 hours ago
It's not just index pages. Generally databases write records into pages, which are then grouped into extents. If the primary key gives an ordering you can create new pages and start filling them up in an orderly fashion. If it's random, you are doing random inserts into pages everywhere all the time, then you start running out of room in pages and have to start splitting them. UUIDv7 solves the most painful parts of this problem in general and is a much better option for a Primary Key than UUIDv1-4.
> Generally
Except for Postgres
Postgresql uses pages too. The records aren't kept in any kind of order, but the indexes are. So uuidv7 is still useful for postgresql because it means inserts are less likely to be spread across many pages in the primary index.