Reference Data JOIN (Azure Stream Analytics)

Updated: April 22, 2016

Applies To: Azure

In a usual scenario, we use an event processing engine to compute streaming data with very low latency. In many cases users need to correlate persisted historical data or a slow changing dataset (aka. reference data) with the real-time event stream to make smarter decisions about the system. For example, join my event stream to a static dataset which maps IP Addresses to locations. This is the only JOIN supported in Stream Analytics where a temporal bound is not necessary.

If a commercial vehicle is registered with the Toll Company, they can pass through the toll booth without being stopped for inspection. We will use a commercial vehicle registration lookup table to identify all commercial vehicles with expired registration.

SELECT I1.EntryTime, I1.LicensePlate, I1.TollId, R.RegistrationId  
FROM Input1 I1 TIMESTAMP BY EntryTime  
JOIN Registration R  
ON I1.LicensePlate = R.LicensePlate  
WHERE R.Expired = ‘1’  
  

Note
Using Reference Data JOIN requires that an input source for Reference Data is defined.