Medallion Architecture
What is Medallion Architecture?
The Medallion Architecture is a data design pattern for a Data Lakehouse. It consists of three layers: bronze, silver, and gold, with each representing a progressively higher level of quality as the data flows through them.
The Layers of the Architecture
- Bronze Layer (Raw Data):
Data, from various sources across the enterprise is ingested into the bronze layer. The data is stored in its raw, “as-is” native format, where the it remains append-only and immutable.
This safeguards data integrity with the ability to provide a historical archive of sources with data lineage and audits.
- Silver Layer (Cleaned, Validated & Transformed Data):
The silver layer is where the ingested data gets structured and enriched. The data can be further used downstream for operational and analytical purposes.
The Silver layer gives the ingested data an overview, enabling data engineers, architects, and analysts to create AI, machine learning, BI & reporting projects in the Gold layer within the Medallion architecture of a Data Lakehouse.
- Gold Layer (Curated, Business-level Data):
This layer houses curated, high-quality data in project-specific databases optimized for efficient querying and analyses to meet business needs.
After the gold stage, the data stored within the lakehouse should be ready for consumption by data teams and business users alike.
Analysts primarily depend on core gold tables for their key tasks, and information shared with clients & external stakeholders is seldom stored beyond this level.
Benefits of Medallion Architecture in a Data Lakehouse
Medallion architecture offers a powerful and organized approach to managing data in your lakehouse and it brings numerous benefits to your data operations:
- Enhanced Data Quality & Governance:
Gradual Refinement: Data progresses through a series of cleaning and transformation steps, ensuring improved accuracy and consistency at each stage.
Historical Integrity: Raw data remains untouched in the bronze layer, preserving the complete and unaltered version of your data history.
Reduced Errors: Validation and standardization in the silver layer minimize downstream errors and inconsistencies.
Improved Data Governance: Layered structure facilitates security and access control mechanisms for sensitive data.
- Improved Analytics Performance:
Optimized Data Layout: The gold layer stores data in a format specifically designed for efficient querying and analysis, and this leads to faster insights.
Reduced Processing Overhead: Pre-computed and aggregated data minimizes the need for repetitive calculations, boosting query performance.
Scalability and Flexibility: The layered design accommodates diverse data sources and easily scales to handle growing data volumes.
- Transparency and Accessibility:
Single Source of Truth: The gold layer serves as a unified and reliable data source for all analytics and reporting needs.
Democratized Data Access: Standardized data formats and clear lineage facilitate data utilization by various stakeholders across the organization.
Version Control and Auditing: Track changes and maintain data lineage within each layer, enabling transparent version control and auditability.
By incorporating these benefits, medallion architecture empowers your data lakehouse to become a reliable and efficient engine for generating insightful analytics and informing data-driven decisions throughout your organization.
FAQs
Can Medallion Architecture be implemented in a hybrid cloud environment?
Yes, Medallion Architecture is adaptable to hybrid cloud environments. The layered approach can be implemented across different cloud platforms and on-premises infrastructure.
What are some common challenges in implementing Medallion Architecture?
- Data Quality: Ensuring data accuracy and consistency throughout the layers can be challenging.
- Data Governance: Establishing clear data ownership and access controls is crucial.
- Technical Expertise: Requires skilled data engineers and architects to design and manage the architecture.
How does Medallion Architecture support data democratization?
By providing a clear and structured data landscape, Medallion architecture makes data accessible to a wider audience. The gold layer, in particular, offers standardized data that can be easily consumed by business users for insights and decision-making.
