uuid-ossp: Unique Identifiers
The uuid-ossp extension can be used to generate a UUID.
Overview
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.
- Go to the Database page in the Dashboard.
- Click on Extensions in the sidebar.
- Search for "uuid-ossp" and enable the extension.
The uuid type
Once the extension is enabled, you now have access to a uuid type.
uuid_generate_v1()
Creates a UUID value based on the combination of computer’s MAC address, current timestamp, and a random value.
UUIDv1 leaks identifiable details, which might make it unsuitable for certain security-sensitive applications.
uuid_generate_v4()
Creates UUID values based solely on random numbers. You can also use Postgres's built-in gen_random_uuid() function to generate a UUIDv4.
Examples
Within a query
_10select uuid_generate_v4();
As a primary key
Automatically create a unique, random ID in a table:
_10create table contacts (_10 id uuid default uuid_generate_v4(),_10 first_name text,_10 last_name text,_10 primary key (id)_10);