UUIDv7

UUIDv7 for Elixir and (optionally) Ecto, using an 18-bit randomly-seeded counter.

Uses suggestions described in Section 6.2 from this IETF Draft to add additional sort precision to a version 7 UUID.

When should I use this package?

• You want sequential, time-based, ordered IDs (per-node).
• You are willing to trade a small amount of raw performance for these guarantees. You are taking a hit for backwards time-leap protection and the counter with rollover protection.

When should I not use this package?

• You don't care about sort/order precision beyond milliseconds.

There are other UUID packages, that only have millisecond precision, for example:

• martinthenth/uuidv7
• bitwalker/uniq

Installation

The package can be installed by adding uuid_v7 to your list of dependencies in mix.exs:

def deps do
  [
    {:uuid_v7, "~> 0.4.2"}
  ]
end

Usage

iex> UUIDv7.generate()
"018e90d8-06e8-7f9f-bfd7-6730ba98a51b"

iex> UUIDv7.bingenerate()
<<1, 142, 144, 216, 124, 16, 127, 196, 158, 92, 92, 74, 83, 46, 116, 173>>

Usage with Ecto

Use this the same way you would use Ecto.UUID. For example:

defmodule MyApp.Blog.Post do
  use Ecto.Schema

  @primary_key {:id, UUIDv7, autogenerate: true}

  @foreign_key_type UUIDv7

  schema "blog_posts" do
    field :text, :string
    # etc.
  end
end