The SQL Server Connector allows you to connect to a remote SQL Server database and retrieve data as requested by the application.
You can use this to provide or modify data in your application. It is mostly used to handle contextual data (that is not expected to change often), but can also provide live data in real-time if the database it is connected to is configured to do so.
Most importantly, it should have service broker functionality enabled, and should allow the creation of queues and table triggers by the user whose credentials are being used.
SQL Server database credentials are required to use this Connector.