uuid-ossp: Unique Identifiers

The uuid-ossp extension can be used to generate a UUID.


A UUID is a "Universally Unique Identifier" and it is, for practical purposes, unique. This makes them particularly well suited as Primary Keys. It is occasionally referred to as a GUID, which stands for "Globally Unique Identifier".

Enable the extension

Note: Currently uuid-ossp extension is enabled by default and cannot be disabled.

  1. Go to the Database page in the Dashboard.
  2. Click on Extensions in the sidebar.
  3. Search for "uuid-ossp" and enable the extension.

The uuid type

Once the extension is enabled, you now have access to a uuid type.


Creates a UUID value based on the combination of computer’s MAC address, current timestamp, and a random value.


Creates UUID values based solely on random numbers. You can also use Postgres's built-in gen_random_uuid() function to generate a UUIDv4.


Within a query

select uuid_generate_v4();

As a primary key

Automatically create a unique, random ID in a table:

create table contacts (
id uuid default uuid_generate_v4(),
first_name text,
last_name text,
primary key (id)