5.2.3. Lakehouse Architecture

💡 First Principle: A Lakehouse combines the flexibility of a data lake (store any format) with the structure of a data warehouse (schema, ACID transactions, SQL queries). It's the "best of both worlds" architecture that eliminates the need to maintain separate lake and warehouse systems.

Traditional Trade-off:

• Data Lake: Cheap storage, any format, but no transactions, poor query performance
• Data Warehouse: Fast queries, ACID transactions, but expensive, only structured data

Lakehouse Solution:

• Store data in open Delta format on cheap object storage
• Delta Lake provides ACID transactions, schema enforcement, time travel
• Query with both Spark and SQL engines

⚠️ Exam Tip: If a question mentions combining "lake flexibility with warehouse reliability" or "Delta Lake format," think Lakehouse architecture.