A Brief About ETL vs Database Testing

Both database testing and ETL(Extract-Transform-Load) testing participate in data validation and verification, but they are different to each other. ETL testing is basically done on data in a data warehouse system, historical data for information and reporting purpose, whereas database testing is basically done on processed data systems where the data comes from different applications or source into the transactional database.

There are some major differences between ETL testing and Database testing:

ETL Testing:

• Business Purpose - It is used for Analytical Reporting, information, and forecasting.

• To validate the data movement from the source to the target system.

• Verification of data count in the source and the target system.

• Check data accuracy by extraction of data, do transformation as per requirement.

• Verifying during the transformation, if table relations – joins and keys – are preserved.

• Its contain data Type - De-normalized data with fewer joins, more indexes, and aggregations.

• In ETL Multidimensional modeling is used.

• ETL testing tools include Informatica, QuerySurge, etc.

Image source google

Database Testing

Database testing more over on data accuracy, valid data, and correctness of data. It involves the following operations −

• Verifying the primary and foreign keys are maintained.

• Verifying valid data values available in the columns of the table.

• Verifying data accuracy in columns. Example − Number of days in a Week column shouldn’t have a value greater than 7.

• Verifying missing data in columns. Check if there are null columns which actually should have a valid value.

• Business purpose - It is used to integrate data from multiple applications, Severe impact.

• It contains data type - Normalized data with more joins.

• In Database testing, ER method modeling is used.

• Common database testing tools include Selenium, QTP, TestComplete etc.

Image source Google

Thanks

Abhimanyu