ksqlDB: SQL on Streams

SQL that doesn't stop

ksqlDB compiles SQL-shaped statements down to Kafka Streams topologies. You get:

• CREATE STREAM / CREATE TABLE over existing topics,
• persistent (continuous) queries that never return,
• pull queries on materialised tables (point lookups against state stores),
• HTTP endpoint for both push and pull.

Great for analyst-driven feature work; less great when you need fine-grained Processor API control — drop down to Kafka Streams when ksqlDB's optimiser gets in your way.

Define orders_stream over the orders topic, then a persistent query that emits a new stream orders_high_value containing only orders ≥ $1,000. (Treat the playground as ksqlDB-script-shaped pseudocode.)