Change Data Capture (CDC) tools are designed to track and manage the changes made in a database, which makes them effective for synchronizing data between different databases or systems. To use CDC tools for database synchronization, you first need to configure the source database to capture the changes. This typically involves enabling CDC on the desired tables. For example, if you are using Microsoft SQL Server, you can enable CDC using the sys.sp_cdc_enable_table stored procedure, which will start tracking changes like INSERTs, UPDATEs, and DELETEs.
Once CDN is enabled, the CDC tool will create change tables that record all the modifications in the tracked tables. This allows you to query the changes at any time without needing to interact directly with the main tables. For instance, in an ETL (Extract, Transform, Load) process, you could extract the change records from these CDC tables regularly (e.g., hourly or daily). You can connect to the CDC logs using SQL queries or API calls and pull only the most recent updates to minimize data movement and ensure that you are working with the latest information.
Finally, after extracting the changes from the source database, the next step is to apply these changes to the target database. Depending on the database systems in use, this may involve straightforward SQL commands or more complex procedures if you need to handle transformations or conflict resolutions. For example, if you're syncing data from a SQL Server database to a PostgreSQL database, you might convert the data format as needed and then insert those changes into the target database. It's essential to maintain a reliable mechanism for tracking which changes have been synced to avoid duplicating data or missing updates. Regularly scheduled jobs or event-driven architectures can help automate this synchronization process.