Description

Change Data Capture (CDC) is a process that identifies and captures changes made to data in a database, and then delivers those changes in near real-time to a downstream process or system. This includes changes such as insertions, deletions, and updates to the data.

How it Works

CDC works by continuously monitoring the source system for any changes made to the data. Whenever a change is detected, it captures and records it in a separate location, such as a database or log file, or sends it to a message broker. The source of change data for CDC is typically the transaction log of a database. As inserts, updates, and deletes are applied to tracked source tables, entries that describe those changes are added to the log. The log serves as input to the capture process, which reads the log and adds information about changes to the tracked table’s associated change table.

Benefits

• Provides real-time or near real-time capture of individual data changes.
• Enables faster data propagation and synchronization between systems.
• Ensures up-to-date destination database with the latest changes.
• Reduces impact on system performance by capturing only changed data.
• Decreases network traffic and resource utilization.
• Provides granular and detailed information about data changes.

Limitations

• Requires a source database that supports CDC.
• May have limitations when working with other database features.
• Requires careful management of the capture process and change tables.
• May have service quotas that need to be managed to ensure optimal performance.

Features

• Can handle a variety of data types and structures.
• Supports both push and pull methods of data capture.
• Provides a historical view of the changes made over time to source tables.