2. OLTP vs OLAP and the Modern Data Stack
2.3 Warehouse and Lakehouse Words
Why. Words change every year: warehouse, data lake, lakehouse.
What. Warehouse — structured tables for SQL analytics. Data lake — files (Parquet/CSV) in cheap storage. Lakehouse — lake storage + table management features (e.g. Delta-style ideas) so SQL and files meet.
How. For this course: raw files land in a lake-like zone; clean tables serve BI. Databricks/Fabric chapters show one vendor view of lakehouse.