Observing data changes with Change Data Capture (CDC)

Change Data Capture (CDC) in ScyllaDB is an advanced feature designed to facilitate real-time data processing by logging all mutations in selected database tables, enabling immediate reactions to data changes. Unlike Apache Cassandra's approach, ScyllaDB's CDC is more integrated, using a regular table format accessible via the CQL protocol, which simplifies the data capture process and resolves issues related to distributed data systems. CDC logs changes in the form of preimage and postimage data, allowing users to track modifications comprehensively. The feature also supports real-time processing applications, such as Kafka Streams or Spark, and provides seamless integration with other systems for data replication and monitoring. While CDC does impact system performance by increasing write operations, it offers enhanced functionality for processing and analyzing rapidly changing data. The feature, initially introduced in ScyllaDB Open Source 3.2 and improved in subsequent releases, remains in development with plans for general availability in ScyllaDB Open Source 4.1.