Change data capture (CDC) helps you identify data that has changed since the last extraction. You can use the data obtained by using CDC to create history databases or perform near-real-time caching. You can also provide the data to message queues (MQs) so that you can consume the data in MQs for analysis and auditing.
OceanBase Change Data Capture (obcdc) provides incremental data of OceanBase Database in real time as a dynamic-link library.
obcdc requests commit logs (clogs), also known as redo logs, of each partition from OceanBase Database by using remote procedure calls (RPCs). It converts clogs to LogMsg data based on the table and column schemas that are obtained by querying OBServer nodes. After obcdc aggregates data changes of each partition involved in a transaction, it provides the changed data of the transaction to an external process row by row.
Application of obcdc
obcdc provides the incremental transaction data of OceanBase Database to external processes. Processes can call obcdc for data synchronization and subscription.
Data synchronization: Data from OceanBase Database is synchronized to other homogeneous or heterogeneous databases for purposes such as logical migration, logical backup, and logical upgrade.
Data subscription: Data from OceanBase Database is synchronized to MQs or data warehouses for purposes such as real-time computing, auditing, and monitoring.
For more information about how to use obcdc, see obcdc development instructions.