The second installment of the DeltaStream 101 series explores how DeltaStream can enrich, filter, and aggregate streaming data from different sources like Apache Kafka and Amazon Kinesis to meet product data needs more efficiently. By using a real-life example, the process demonstrates enriching a clicks stream by integrating user data from a Kinesis changelog, which allows for counting clicks per URL and device type. This enriched stream is then used to aggregate clicks per URL and region, facilitated by DeltaStream's capability to perform temporal joins and maintain updated user information. The setup involves declaring a Kinesis store and creating changelogs to manage user information updates. By leveraging SQL-based queries, developers can build complex streaming applications quickly without the need for extensive maintenance, showcasing DeltaStream’s potential to simplify and enhance stream processing.