Reviewed by Aditya Kumar · Last reviewed 2026-03-24
Architectural logic: Job bookmarks track last processed keys (paths, partition values). Next run skips already processed data. Why: Avoid full scans; reduce cost and time. For JDBC: Use column (e.g., updated_at) as bookmark. Scalability: Many partitions can slow bookmark...
Architectural logic: Job bookmarks track last processed keys (paths, partition values). Next run skips already processed data. Why: Avoid full scans; reduce cost and time. For JDBC: Use column (e.g., updated_at) as bookmark. Scalability: Many partitions can slow bookmark overhead. Best practice: Deterministic ordering; avoid manual bookmark changes; reset for full refresh.
Red Flag: Full scan when bookmark could work. Pro-Move: 'Bookmarks on file source—daily job processes only new partitions; runtime dropped from 2h to 15 min.'
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