Working with Azure SQL Triggers in Azure Functions

We can now use SQL triggers in Azure Functions to listen to SQL Change Tracking!

Azure SQL triggers for Azure Functions came into public preview for C# Functions last month. When you enable Change Tracking on a table in Azure SQL Database, Managed Instance or SQL Server (yes, on-prem SQL Server), you can create a function that will be triggered every time a row is created, updated or deleted.

In this article, we’ll dive into the details of SQL Trigger Functions, how Change Tracking works and how we can configure our Functions to listen to SQL Change Tracking. We’ll finish off by discussing how we can monitor how our functions scale as more changes are being processed using the scale controller logs.

About SQL Trigger Functions

As I mentioned before, the Azure SQL trigger uses SQL change tracking functionality to monitor a SQL table for changes, and then triggers a Function when a row is created, updated or deleted in that table.

At the time of writing, this feature is in public preview. Currently, you are limited to C# Functions that are hosted on either Premium or Dedicated plans. Another limitation is that isolated worker process functions aren’t supported yet.