---
title: "Schedules: cron-triggered functions"
description: "Run a function on a cron schedule using pg_cron"
---

Schedules invoke functions on a recurring cron expression. [pg_cron](https://github.com/citusdata/pg_cron) fires an HTTP request to the function URL at each tick and logs the result.

## Concepts

A schedule is a cron expression, a target URL, and headers. On creation, `${{secrets.KEY}}` placeholders in headers are resolved and encrypted with `pgcrypto`. At each tick, `execute_job()` decrypts headers, calls the function, and writes status and duration to `schedules.job_logs`.

## Usage

Standard 5-field cron (no seconds). Reference secrets in headers instead of hardcoding keys.

```text
*/5 * * * *   every 5 minutes
0 * * * *     every hour
0 0 * * *     daily at midnight
0 9 * * 1     every Monday at 9am
0 0 1 * *     first of every month
```

Create via dashboard or SQL:

```sql
select schedules.create_job(
  name       => 'daily-cleanup',
  schedule   => '0 0 * * *',
  url        => 'https://myapp.functions.insforge.app/cleanup',
  headers    => jsonb_build_object('Authorization', 'Bearer ${{secrets.CRON_TOKEN}}')
);
```

## Limits

Minimum interval is 1 minute (pg_cron). Failed runs are logged but not retried, so the function must be idempotent. Deleting a referenced secret breaks every job using it until you update or disable the schedule.

## More resources

- [pg_cron docs](https://github.com/citusdata/pg_cron) for cron syntax.
- [Functions overview](/core-concepts/functions/overview) for the runtime.
- [crontab.guru](https://crontab.guru) to check an expression.
