ETL stands for Extract-Transform-Load, and as the name suggests, these are three different tasks combined into one tool. These tasks are then used to extract data from one database and place it into another. 

The First step is Data extraction, which is extracted from the online transactional processing (OLTP) database. Now, this is further modified to meet the data warehouse guidelines. The last step, “Load,” is the process of uploading data that has been extracted & transformed.


ETL testing is the process that is used to check the authenticity of the data extracted from a source. The aim is to make sure the data placed is accurate and authentic. ETL TESTING not only overviews the real data but also validates the data at different stages. A series of tasks do this to troubleshoot each stage of the change that ensures the ETL’s effectiveness. 

ETL validates the Data’s accuracy, runs diagnoses, checks errors, and checks the efficiency of the data. So ETL and data warehouse testing are fundamental for accurate execution and outcome.

This testing is applied to ensure that the data loaded from a specific source to the destination is correct. It also involves a thorough investigation. That is performed on data at different stages used between source and destination. 

ETL Testing Training: Steps involved in the ETL process

ETL also goes through different steps, just like other testing software. The main processes involved in the ETL testing process are as follows.

  1. Identifying data sources and requirements
  2. Data acquisition
  3. Business logic and dimensional Modelling
  4. Build and populate data
  5. Build Reports

There are different types of ELT testing that you must know in ETL TESTING TRAINING, like different processes. Some of the elt testings are mentioned below.

etl testing training

Production Validation Testing

This type is also known by many as Table balancing” or “production reconciliation.” This testing is performed on the Data that is being moved into the production system. For correct business decisions, the order of the data must be correct. This order in your production system positively affects the business.

Another amazing tool that boosts your testing process is Informatica Data Validation. This tool provides management capabilities and ETL testing automation. Ensuring that the provided Data does not jeopardize production systems.

Source to Target Testing (Validation Testing) 

This type of testing is performed to authenticate whether the data values transformed are the anticipated data values or not.

Application Upgrades

This type of ETL testing can be produced, saving substantial test development time. This testing checks whether the data extracted from an earlier application are the same as the data in the latest application.

Metadata Testing 

Metadata testing includes testing data type check, data length check, and index/constraint check. 

Types of bugs 

User interface bugs/cosmetic bugs

  • Related to GUI of application
  • Font style, font size, colors, alignment, spelling mistakes, navigation, and so on
  • Boundary Value Analysis (BVA) related bug
  • Smallest and largest values
  • Equivalence Class Partitioning (ECP) related bug
  • Valid and invalid type