pg_slug_gen

Overview

Version

Build

You can build the RPM / DEB packages for pg_slug_gen using pig build:

pig build pkg pg_slug_gen         # build RPM / DEB packages

Install

You can install pg_slug_gen directly. First, make sure the PGDG and PIGSTY repositories are added and enabled:

pig repo add pgsql -u          # Add repo and update cache

Install the extension using pig or apt/yum/dnf:

pig install pg_slug_gen;          # Install for current active PG version

pig ext install -y pg_slug_gen -v 18  # PG 18
pig ext install -y pg_slug_gen -v 17  # PG 17
pig ext install -y pg_slug_gen -v 16  # PG 16
pig ext install -y pg_slug_gen -v 15  # PG 15

dnf install -y pg_slug_gen_18       # PG 18
dnf install -y pg_slug_gen_17       # PG 17
dnf install -y pg_slug_gen_16       # PG 16
dnf install -y pg_slug_gen_15       # PG 15

apt install -y postgresql-18-pg-slug-gen   # PG 18
apt install -y postgresql-17-pg-slug-gen   # PG 17
apt install -y postgresql-16-pg-slug-gen   # PG 16
apt install -y postgresql-15-pg-slug-gen   # PG 15

Create Extension:

CREATE EXTENSION pg_slug_gen;

Usage

Sources: repo README, official PGXN release page, official release README, official release SQL, official release metadata

pg_slug_gen generates timestamp-based slugs with cryptographic randomness. The official 1.0.0 release describes it as a secure, URL-friendly short ID generator where the requested length selects the timestamp precision.

CREATE EXTENSION pg_slug_gen;

SELECT gen_random_slug();
SELECT gen_random_slug(13);

Function

• gen_random_slug(slug_length int DEFAULT 16) returns text

The release SQL comment and README document these supported values:

• 10: seconds
• 13: milliseconds
• 16: microseconds, also the default
• 19: nanoseconds

Precision And Format

Each precision maps to a timestamp width and a fixed slug shape:

• 10 digits: 5-5 format, 11 characters total
• 13 digits: 6-7 format, 14 characters total
• 16 digits: 8-8 format, 17 characters total
• 19 digits: 9-10 format, 20 characters total

The README states the collision-free window is bounded by timestamp precision: at most 1 insert per second, millisecond, microsecond, or nanosecond respectively.

Examples

SELECT gen_random_slug();
SELECT gen_random_slug(10);
SELECT gen_random_slug(16);

CREATE TABLE products (
  id serial PRIMARY KEY,
  name text NOT NULL,
  slug text DEFAULT gen_random_slug() UNIQUE
);

How It Works

The official README describes this algorithm:

• take the current timestamp at the chosen precision
• map each digit to a QWERTY-based character bucket
• choose one random character from that bucket with pg_strong_random()
• insert a hyphen at the midpoint

Caveats

• This is a secure short-ID generator, not a text transliteration or title-to-URL slugifier.
• Same-timestamp collisions are still possible; upstream only claims uniqueness when inserts do not exceed one per chosen time unit.
• The catalog URL is the current https://github.com/nandoolle/pg_slug_gen repository; the PGXN release metadata still points to the older fernandoolle GitHub URL.
• The curated package matrix targets PostgreSQL 15 through 18, while PGXN metadata only declares a minimum PostgreSQL version. Use the catalog matrix for packaged availability.