Hi @NathanSundarara, Certainly! Let’s explore how you can work with Delta Live Tables (DLT) in the context of Lakehouse federation and materialized views.
Delta Live Tables (DLT):
Materialized Views and Recomputation:
- Materialized views in DLT are powerful constructs for maintaining derived datasets. They allow you to create and keep up-to-date views based on declarative queries.
- In your case, you’ve been loading data incrementally for the last 3 days and recomputing the materialized view. However, you’re encountering a full recompute issue.
Handling Existing Records:
- When recomputing materialized views, DLT processes records as required to return accurate results for the current data state.
- To address existing records, consider using window functions to recompute and keep the last record based on timestamps. This approach ensures that only necessary changes are applied.
DLT and Apply Changes:
- The “Apply changes” operation in DLT is designed for incremental updates. However, it seems that the data changes are causing errors.
- If you’re encountering issues with “Apply changes,” consider the following alternatives:
- Delta Merge: Use Delta’s built-in merge operation to update existing records based on keys efficiently. This can be more efficient than full recomputation.
- Change Data Capture (CDC): Implement CDC strategies to capture and process only the changed data. DLT supports materialized views for CDC processing.
- Custom Logic: Write custom logic to handle incremental updates based on your use case.
Lakehouse Federation:
- The newly announced Lakehouse Federation allows you to access external data sources from Databricks.
- You can use Lakehouse federation to ingest data from supported sources into DLT pipelines.
- Ensure that your DLT pipeline configuration includes the necessary settings for the Lakehouse federation.
Iterate and Monitor:
- As you experiment with different approaches, monitor execution times, resource utilization, and data quality.
- Adjust your pipeline based on performance and reliability requirements.
Remember that DLT provides a robust abstraction layer, but fine-tuning your pipeline often involves a combination of declarative definitions and custom logic.
Feel free to iterate and adapt your solution based on your specific data requirements.