Postgres Data Freshness Monitoring with Email Alerts

This n8n workflow automates monitoring of Postgres database tables to ensure data freshness. It queries specified tables for the most recent timestamp in a designated date column (e.g., 'last_updated' or event timestamp), calculates days since last update, filters out fresh tables (default: updated within 3 days), and emails a list of stale tables with details.

Benefits include proactive detection of data pipeline issues, preventing reliance on outdated data in analytics or apps, and reducing manual checks. Ideal for ETL processes, event logging, or any Postgres setup where timely updates are critical.

Use cases: Monitor expense tables in HR/ops for recent submissions, track sales data freshness in e-commerce, ensure IoT sensor logs are current, or audit compliance data. Customize staleness window, tables monitored, and integrate with alerting workflows for Slack/Teams notifications.

Setup is straightforward: Add Postgres/email credentials, edit the 'Produce tables + date columns' node with your [table, column] pairs, tweak thresholds, and activate on a schedule (e.g., daily cron).