pg_cron

Overview

require cron.database_name

Version

Install

You can install pg_cron directly. First, make sure the PGDG repository is added and enabled:

pig repo add pgdg -u          # Add PGDG repo and update cache

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

• Install
• pig
• dnf
• apt

pig install pg_cron;          # Install for current active PG version

pig ext install -y pg_cron -v 18  # PG 18
pig ext install -y pg_cron -v 17  # PG 17
pig ext install -y pg_cron -v 16  # PG 16
pig ext install -y pg_cron -v 15  # PG 15
pig ext install -y pg_cron -v 14  # PG 14

dnf install -y pg_cron_18       # PG 18
dnf install -y pg_cron_17       # PG 17
dnf install -y pg_cron_16       # PG 16
dnf install -y pg_cron_15       # PG 15
dnf install -y pg_cron_14       # PG 14

apt install -y postgresql-18-cron   # PG 18
apt install -y postgresql-17-cron   # PG 17
apt install -y postgresql-16-cron   # PG 16
apt install -y postgresql-15-cron   # PG 15
apt install -y postgresql-14-cron   # PG 14

Preload:

shared_preload_libraries = 'pg_cron';

Create Extension:

CREATE EXTENSION pg_cron;

Usage

beware that cron.database has to be set before adding to shared_preload_libraries

-- Delete old data on Saturday at 3:30am (GMT)
SELECT cron.schedule('30 3 * * 6', $$DELETE FROM events WHERE event_time < now() - interval '1 week'$$);
 schedule
----------
       42

-- Vacuum every day at 10:00am (GMT)
SELECT cron.schedule('nightly-vacuum', '0 10 * * *', 'VACUUM');
 schedule
----------
       43

-- Change to vacuum at 3:00am (GMT)
SELECT cron.schedule('nightly-vacuum', '0 3 * * *', 'VACUUM');
 schedule
----------
       43

-- Stop scheduling jobs
SELECT cron.unschedule('nightly-vacuum' );
 unschedule 
------------
 t

SELECT cron.unschedule(42);
 unschedule
------------
          t

-- Vacuum every Sunday at 4:00am (GMT) in a database other than the one pg_cron is installed in
SELECT cron.schedule_in_database('weekly-vacuum', '0 4 * * 0', 'VACUUM', 'some_other_database');
 schedule
----------
       44

-- Call a stored procedure every 5 seconds
SELECT cron.schedule('process-updates', '5 seconds', 'CALL process_updates()');

-- Process payroll at 12:00 of the last day of each month
SELECT cron.schedule('process-payroll', '0 12 $ * *', 'CALL process_payroll()');

Crontab format:

 ┌───────────── min (0 - 59)
 │ ┌────────────── hour (0 - 23)
 │ │ ┌─────────────── day of month (1 - 31) or last day of the month ($)
 │ │ │ ┌──────────────── month (1 - 12)
 │ │ │ │ ┌───────────────── day of week (0 - 6) (0 to 6 are Sunday to
 │ │ │ │ │                  Saturday, or use names; 7 is also Sunday)
 │ │ │ │ │
 │ │ │ │ │
 * * * * *