Stream analytics is a fully managed data and event processing engine that helps in providing real-time analytics on the data getting streamed. While Cosmos DB and Azure SQL provide data that is already available in their storage, stream analytics provides analytics computation on data that is getting streamed live as they are ingested. They are not queries against data stored in permanent storage. This is an extremely powerful capability for getting real-time insights instead of finding insights much after the event occurred.

The beauty of stream analytics lies in the fact that the data can come from anywhere--applications, IoT devices, other Azure services, such as event hubs or any other system.

The other fundamental core tenet of stream analytics is the processing of a large volume of data. It has been created to process a huge quantity of data and extract insights and information out of it in real-time.

It also allows necessary integration with other systems and services to act on the extracted insights, such as sending notifications, raising alerts, logging into multiple log analytics services, and reporting using visualization tools.

The crux of stream analytic lies in the fact that data of a high volume, velocity, and multiple format can be processed by a single service in real-time and means actions can be taken on the same.

The architecture of stream analytics is shown in the following diagram:

Stream analytics provides Extract-Transform-Load (ETL) functionality for real-time processes. It defines a job that is configured with incoming data along with source of data, transformations, and the output data log with destinations.

There are many use cases for implementing stream analytics. They are as follows:

• Many industries need real-time analytic solutions, such as parking system, highway toll-booth systems, movie ticket sales, and so on
• Social media sentiment analysis
• Web traffic analysis
• Log analytics for security and other breaches and more
• Infrastructure monitoring

There are multiple components that are part of the Azure stream analytics service.