Extract Transform and Load

 ETL:

ETL - extract, transform, and load. Extracting data from outside source systems. Transforming raw data to make it fit for use by different departments. Loading transformed data into target systems like data mart or data warehouse.

Why ETL testing is required? 

• To verify the correctness of data transformation against the signed off business requirements and rules. • To verify that expected data is loaded into data mart or data warehouse without loss of any data. • To validate the accuracy of reconciliation reports (if any e.g. in case of comparison of report of transactions made via bank ATM – ATM report vs. Bank Account Report). • To make sure complete process meet performance and scalability requirements • Data security is also sometimes part of ETL testing • To evaluate the reporting efficiency

Tools you have used for ETL testing:

1. Data access tools e.g., TOAD, WinSQL, AQT etc. (used to analyze content of tables) 2. ETL Tools e.g. Informatica, DataStage 3. Test management tool e.g. Test Director, Quality Center etc. ( to maintain requirements, test cases, defects and traceability matrix).