Confluent has recently released another version of KSQL, or should I say the aptly renamed ksqlDB. It is currently community licensed and fully available on Github (https://github.com/confluent/ksql). Whether you currently have a Kafka instance up and running or not, you can be up and running with this on Docker Compose fairly quickly if you wanted to try some things out on a VM.
Two of the main features it boasts are pull queries and connector management.
A pull query is a form of query issued by a client that retrieves a result as of "now," like a query against a traditional RDBS. Pull queries have limitations ANSI SQL does not, but nevertheless, potentially greatly simplify the architecture of typical stream processing use cases.
A pull query has the following general structure:
SELECT select_expr [...] FROM aggregate_table WHERE ROWKEY=key [AND window_bounds];
As aforementioned, ksqldb also integrates with Kafka Connect as well as create and manage connectors.
I look forward to taking more time to test out these features, and I'm already anxious for the next release.
you can find great documentation on ksqldb at: