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Home/Questions/SQL/Building ETL pipelines to capture changes when new records are inserted into source tables?

Building ETL pipelines to capture changes when new records are inserted into source tables?

SQLeasy0.3 min readPremium

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**Patterns:** (1) Incremental: watermark (max id/updated_at), query WHERE id > watermark. (2) CDC: Debezium, AWS DMS—log-based, low latency. (3) Hash/checksum: compare batches. (4) MERGE: upsert by key. **Snowflake:** Stage + MERGE. Store last watermark in state table. Use event time, not process time, for late arrivals....

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