Change Data Capture (CDC) is a technique used in databases and data integration systems to capture and track changes made to data in real-time. It enables the identification and extraction of individual data changes, such as inserts, updates, and deletes, and propagates those changes to other systems or processes that need to be aware of the updates.
The primary purpose of CDC is to keep different systems or components synchronized and updated with the latest changes in a source system without the need for manual intervention or full data replication. By capturing and delivering only the changed data, CDC provides a more efficient and optimized way to maintain data consistency across multiple systems.
CDC typically works by monitoring the database transaction logs, which are records of all changes made to the database. When a database transaction occurs, CDC captures the relevant information from the transaction log and transforms it into a format suitable for consumption by downstream systems. The captured changes can be delivered to other databases, data warehouses, analytics platforms, or any other system that requires real-time data updates.
CDC offers several benefits, including:
- Real-time data synchronization: CDC allows systems to stay up-to-date with the latest changes in the source system, minimizing data latency and ensuring timely availability of information.
- Reduced processing overhead: By capturing and propagating only the changes, CDC avoids the need for full data transfers or comparisons, resulting in reduced network bandwidth and processing requirements.
- Improved data integration: CDC simplifies the integration of data from multiple systems by providing a standardized mechanism to capture and deliver changes across different platforms.
- Auditing and compliance: CDC logs and tracks every change made to the data, providing a reliable audit trail for compliance purposes and enabling data lineage and traceability.
CDC is commonly used in scenarios such as data replication, data warehousing, business intelligence, real-time analytics, and maintaining data consistency across distributed systems. It is a valuable tool for organizations that require timely and accurate data synchronization across multiple systems.