CDC Change Data Capture
Change Data Capture — streaming all DB changes (insert/update/delete) as events without modifying application code. The source is typically the DB log (binlog, WAL). Debezium is the de-facto open source tool.
Use cases: replicate to a data warehouse (Snowflake, BigQuery), invalidate cache, trigger downstream jobs, microservice event bus, audit log. Pull CDC: the app polls a last-modified timestamp (brittle). Log CDC: reads the binary log, also captures deletes — Debezium, Maxwell, Aurora MySQL native CDC. Outputs to Kafka, Pulsar, Kinesis. Competitors: AWS DMS, Striim, Fivetran (proprietary). Quickly becoming a standard architecture for the modern data stack.