A KSQL query is a declarative SQL statement that continuously processes Kafka-backed streams or tables. Unlike a conventional query over a static snapshot, it evaluates events as they arrive and can publish changing results. ksqlDB deploys queries across a server cluster, reducing the coding and administrative work of a standalone stream-processing application. section 8.4.1
KSQL query
A KSQL query is a SQL-based query that continuously processes streams or tables backed by Kafka topics.
How Kafka for Architects covers it
- How deep it goes
- Explains filtering, aggregation, grouping, windows, and cluster execution, while deferring low-level programming details.
- Examples
- Demonstrates expensive-order filtering, country counts, hourly tumbling windows, and typed Orders streams.
- What you can do after
- Apply it via ksqlDB to define, filter, and aggregate continuously changing Kafka data.
- How it connects
- Connects SQL, Kafka topics, stream processing, Kafka Streams, REST APIs, and event-driven architecture.
Related concepts
- ksqlDBused by · ksqlDB is a streaming database system that uses SQL-like statements to process Apache Kafka event streams continuously.
This explainer was generated by Manning's knowledge graph from the text of Kafka for Architects. The section links point to the parts of the book it draws on.