UUID v7 Explained
A look at the internal structure of the latest standard, v7, and how to adopt it.
Structure
The first 48 bits hold a Unix millisecond timestamp, followed by the version and variant bits and the remaining random data. This lets v7 satisfy both chronological ordering and uniqueness at the same time.
Advantages
New values are inserted sequentially at the end of the index, greatly reducing the page-split problem of random v4. You can also derive the approximate creation time directly from the ID, which is useful for logging and sorting.
Adoption
Some languages do not yet offer v7 in their standard library, so you may need a separate package. When migrating an existing v4 table, the safest approach is incremental: apply v7 only to newly created records.