n8n & PostgreSQL: Daily Data Alert Setup 📊

Learn how to build a daily data-quality alert system using n8n and PostgreSQL.
In this step-by-step walkthrough, I show how to connect Postgres, write a simple SQL check, add conditional logic, and trigger an automated email alert every morning.

This demo uses test data, but the workflow works the same way on real production tables.

What you’ll learn:
• How to run n8n and PostgreSQL locally using Docker
• How to connect n8n to your database
• How to write and execute a data-quality SQL check
• How to use the IF node for dynamic logic
• How to send automated email alerts when issues are detected

Workflow summary:

Schedule trigger at 9 AM

Postgres node runs a SQL check

IF node checks for issues

Gmail node sends formatted alerts

If you want the full SQL, workflow JSON, or help building your own automations, comment below or reach out.

Tools used:
n8n, PostgreSQL, Docker, Gmail