Definition
ETL, or Extract Transform Load, is a foundational data integration process used to move data from various sources into a central repository like a data warehouse. It involves three key stages: extracting data from its original location, transforming it into a usable format, and loading it into the target system. This process is crucial for consolidating disparate data, enabling comprehensive analysis, and supporting informed decision-making within an organization. For instance, a retail company might use ETL to pull sales data from point-of-sale systems, inventory databases, and online platforms into a single data warehouse for sales trend analysis. ETL is distinct from ELT (Extract Load Transform), where data is loaded first and transformed later, often within the target data warehouse itself. Understanding ETL is vital for cloud data management and appears in domains related to data warehousing and analytics on exams like AWS Certified Solutions Architect Associate.