A naukri.com initiative
Amazon
2w
73
Image Credit: Amazon
Implement historical record lookup and Slowly Changing Dimensions Type-2 using Apache Iceberg
- Tracking and analyzing changes over time has become essential in today’s data-driven world. Apache Iceberg provides a feature known as the change log view that enables us to track insertions, updates, and deletions, giving us a complete picture of how our data has evolved.
- Slowly Changing Dimensions (SCD) Type-2 creates new rows for changed data instead of overwriting existing records, allowing for comprehensive tracking of changes over time.
- With Iceberg, you can create a dedicated view of SCD Type-2 on top of the change log view, eliminating the need to implement specific handling to make changes on SCD Type-2 tables. This approach combines the power of Iceberg’s efficient data management with the historical tracking capabilities of SCD Type-2.
- SCD Type-2 requires additional fields such as effective_start_date, effective_end_date, and current_flag to manage historical records. In traditional implementations, SCD Type-2 requires specific handling in all INSERT, UPDATE, and DELETE operations that affect those additional columns.
- Using Iceberg’s change log view, you can obtain the history of a given record directly from the Iceberg table’s history, without needing to create a separate table for managing record history. This streamlined method not only makes the implementation of SCD Type-2 more straightforward, but also offers improved performance and scalability for handling large volumes of historical data in CDC scenarios.
- SCD Type-2 enables point-in-time analysis, provides detailed audit trails, aids in data quality management, and helps meet compliance requirements by preserving historical data. It is particularly relevant to Change Data Capture (CDC) scenarios, where capturing all data changes over time is crucial.
- This tutorial demonstrates how to implement historical record management and SCD Type-2 using Apache Iceberg, focusing on a typical CDC architecture. It also showcases how a change log view aids historical analysis, improving possibilities for advanced time-based analytics, auditing, and data governance.
- The change log view does not lose any historical record changes even when undergoing compaction. However, the change log view loses historical record changes corresponded to snapshots deleted with expire_snapshots and Glue Data Catalog automatic snapshot deletion. It is not supported in MoR tables.
- Implementing Iceberg’s change log view and SCD Type-2 enables you to manage the history of records and tables without extra effort. It shows how this approach can be implemented, showcasing the efficiency and flexibility it brings to historical data analysis and CDC processes.
- Apache Iceberg makes the implementation of SCD Type-2 more manageable and offers improved performance and scalability for handling large volumes of historical data in CDC scenarios.
Read Full Article
4 Likes
For uninterrupted reading, download the app