What Is a Change Data Capture Stream?
Change data capture (CDC) reads a database transaction log and turns committed row changes into an ordered stream of events. Downstream consumers subscribe to the stream to replicate data, update caches, or feed analytics in near real time. Because it taps the log, CDC captures every change without polling or modifying application queries.
Why it matters
Keeping derived systems in sync by polling is slow and lossy, whereas a change stream delivers updates as they happen. CDC is a common backbone for the outbox relay, cache invalidation, and data pipelines.
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