Glossary · Database

ETL

Extract, Transform, Load–a data integration process that moves data from source systems into a data warehouse.

ETL stands for Extract, Transform, Load–the three steps in a data integration pipeline. Extract pulls data from source systems (databases, APIs, files, SaaS applications). Transform cleanses, validates, deduplicates, and reshapes the data to fit the target schema–this may include type conversions, aggregations, lookups, and business rule applications. Load writes the processed data into the destination (typically a data warehouse). Modern variations include ELT (Extract, Load, Transform), where raw data is loaded first and transformed within the warehouse using its compute power. Popular ETL tools include Apache Airflow, dbt, Fivetran, Stitch, and Talend.

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