Different joins in Structured Streaming

One of the key features of Structured Streaming is its ability to join different types of data streams together in one sink.

Stream-stream joins

Stream-stream joins, also known as stream-stream co-grouping or stream-stream correlation, involve joining two or more streaming data sources based on a common key or condition. In this type of join, each incoming event from the streams is matched with events from other streams that share the same key or satisfy the specified condition.

Stream-stream joins enable real-time data correlation and enrichment, making it possible to combine multiple streams of data to gain deeper insights and perform complex analytics. However, stream-stream joins present unique challenges compared to batch or stream-static joins, due to the unbounded nature of streaming data and potential event-time skew.

One common approach to stream-stream joins is the use of windowing operations. By defining overlapping or...