Understanding the Medallion Architecture
The Medallion Architecture is all about managing data in a way that facilitates efficient data engineering and analytics. Let’s break down the architecture into its essential layers:
1. Bronze Layer (Raw Data)
- The Bronze layer serves as the initial landing zone for data from external source systems.
- Here, we maintain the data structures exactly as they exist in the source systems, including any additional metadata columns (e.g., load date/time, process ID).
- The focus in this layer is on quick Change Data Capture (CDC) and historical archiving of source data (cold storage).
- It ensures data lineage, auditability, and the ability to reprocess data if needed without re-reading from the source.
2. Silver Layer (Cleansed and Conformed Data)
- In the Silver layer, data from the Bronze layer undergoes matching, merging, conformance, and cleansing.
- We create an “Enterprise view” of key business entities, concepts, and transactions.
- Examples include master customers, stores, non-duplicated transactions, and cross-reference tables.
- The Silver layer enables self-service analytics, ad-hoc reporting, advanced analytics, and machine learning.
- Data engineers, data scientists, and departmental analysts can leverage this layer for their projects.
3. Gold Layer (High-Quality Data)
- The Gold layer represents the pinnacle of data quality.
- It contains data that has undergone complex transformations, business rules, and enrichment.
- This layer serves as the foundation for enterprise-wide reporting, dashboards, and strategic decision-making.
- Data in the Gold layer is well-structured, reliable, and ready for consumption by business users.
Building Data Pipelines with Databricks
Databricks provides powerful tools like Delta Live Tables (DLT) for creating Medallion Architecture-based data pipelines. Here’s how you can get started:
- Write a few lines of code to define your Bronze, Silver, and Gold tables.
- Utilize streaming tables and materialized views for incremental data refresh.
- Combine streaming and batch processing seamlessly.
Conclusion
The Medallion Architecture empowers organizations to manage data effectively, ensuring that it evolves from raw form to high-quality insights. By following this logical framework, you’ll create a robust data foundation for your Lakehouse, enabling data-driven decision-making and innovation.