SQL Server › Change Data Capture (CDC)

How would you use Change Data Capture to build a near real time data synchronization pipeline between an operational database and a data warehouse?

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Answer

You would schedule a job that periodically queries the CDC change functions for each tracked table since the last successful run, apply those specific inserted, updated, and deleted rows to your data warehouse tables, and keep track of the last processed log sequence number so each run only picks up genuinely new changes.
-- Store the last processed LSN and use it as the starting point
-- for the next scheduled synchronization run
SELECT * FROM cdc.fn_cdc_get_net_changes_dbo_Orders(@last_lsn, @current_lsn, 'all');
Real-world example A retail analytics team builds a synchronization job that runs every ten minutes, pulling only the changed orders since the last run using CDC, keeping their data warehouse nearly real time without the heavy load of reprocessing the entire orders table repeatedly.

Common follow-ups: How do you handle a situation where the synchronization job fails partway through processing changes?;What is the retention period for CDC change data, and how do you configure it?