ETL Pipeline for Data Engineering: A Beginner's Guide to Extract, Transform, and Load

An ETL pipeline is the core data-engineering workflow that turns scattered raw payloads — database rows, API responses, log files, SaaS exports — into clean, trusted data inside a warehouse where analysts and BI tools can use it. ETL stands for Extract, Transform, Load : pull raw data from many source systems, reshape and clean it into a consistent schema, then write it into a destination like Amazon Redshift, Snowflake, or a data lake. Every fresher data-engineering interview probes the same th