Azure Event Hubs, Azure Stream Analytics, and Power BI. When you are designing your stream processing solution, one consideration is interoperability. Azure Event Hubs, Azure Stream Analytics, and Power BI are compatible with each other and can be used seamlessly to implement your data stream processing design. Other products are available on the Azure platform for streaming, such as HDInsight 3.6, Hadoop, Azure Databricks, Apache Storm, and WebJobs.

Windowed aggregates. Windowing is provided through temporal features like tumbling, hopping, sliding, session, and snapshot windows. Aggregate functions are methods that can calculate averages, maximums, minimums, and medians. Windowed aggregates enable you to aggregate temporal windows.

Partitions. Partitioning is the grouping of similar data together in close physical proximity in order to gain more efficient storage and query execution speed. Both efficiency and speed of execution are attained when data with matching partition keys is stored and retrieved from a single node. Data queries that pull data from remote datastores, different partition keys, or data that is located on more than a single node take longer to complete.

Time management. The tracking of the time when data is streaming into an ingestion point is crucial when it comes to recovering from a disruption. The timestamps linked to an event message, such as event time, arrival time, and the watermark, all help in this recovery. The event time identifies when the data message was created on the data‐producing IoT device. The arrival time is the enqueued time and reflects when the event message arrived at the ingestion endpoint, like Event Hubs.

Watermark. As shown in Figure 7.41, the watermark is a time that reflects the temporal time frame in which the data was processed by the stream processor. If the time window is 5 seconds, all event messages processed within that time window will receive the same watermark.