ETL Testing

Extract, Transform, Load (ETL) is the general procedure of copying data from one or more data sources into a destination system which represents the data differently from the source(s). The ETL process is often used in data warehousing.

• Data extraction involves extracting data from homogeneous or heterogeneous sources
• Data transformation processes data by cleaning and transforming them into a proper storage format/structure for the purposes of querying and analysis
• Data loading describes the insertion of data into the target data store, data mart, data lake or data warehouse.

A properly designed ETL system extracts data from the source systems, enforces data quality and consistency standards, conforms data so that separate sources can be used together, and finally delivers data in a presentation-ready format.“