Send SMS alerts based on database queries (Twilio and Postgres)

This workflow automatically queries a Postgres database to find outlier readings for which SMS notifications have not been sent.
This is Workflow 2 in the blog tutorial Database activity monitoring and alerting.

Prerequisites

• A Postgres database set up and credentials
• A Twilio account and credentials

Nodes

• Cron node triggers the workflow every minute, so the database is queried at regular intervals.
• Postgres nodes extract values from, and update values in the database.
• Twilio node sends an alert SMS about the outlier reading to a specified phone number.
• Set node sets the notification value to true.