What is Delta Lake, and have you used any of the Databricks‑specific features like Unity Catalog or Lakehouse architecture?

Delta Lake is an open‑source storage layer that brings ACID transactions, scalable metadata handling, and schema enforcement to data lakes. It stores data in Parquet files and maintains a transaction log (the Delta Log) that records every change, enabling features like time travel, upserts, and schema evolution. Unity Catalog is Databricks’ unified governance layer that provides fine‑grained access control, lineage, and catalog management across all data assets. Lakehouse architecture combines the best of data warehouses and data lakes: it stores raw data in a lake (e.g., Delta Lake) while offering SQL‑based analytics, schema enforcement, and performance optimizations typical of warehouses. I have used Delta Lake to build reliable ETL pipelines, leveraged Unity Catalog for role‑based access control on tables, and designed a Lakehouse solution that supports both batch and streaming analytics on a single platform.