ETL Testing Roles - ETL Testing

What are ETL tester’s Roles?

An ETL tester is basically responsible in validating the data sources, in the extraction of data from sources, applying the transformation logic, and loading the data in the target tables.

The main responsibilities of an ETL tester are stated below.

• Verify the Tables in the Source System
• Verification of tables involves the below listed operations −
• In Count check
• Reconcile records with the source data
• In Data type check
• Ensure no spam data loaded
• In removing duplicate data
• To check all the keys are in place

Apply Transformation Logic

• Transformation logic is applied before loading the required data. This involves the below listed operations −
• Data threshold validation check, for suppose, age value shouldn’t be greater than 100.
• Record count check should be done, i.e before and after the transformation logic is applied.
• Data flow validation from the staging area to the intermediate tables.
• Surrogate key check.

Data Loading

• Data is loaded from the staging area to the target system. This involves the below listed operations −
• To record the count check from the intermediate table to the target system.
• To ensure the key field data is not missing or Null.
• To check if the aggregate values and calculated measures are loaded in the fact tables.
• To check modeling views based on the target tables.
• To check if CDC has been applied on the incremental load table.
• Data check in dimension table and history table check.
• To check the BI reports w.r.t the loaded facts and the dimension tables as per the expected outputs.

Testing the ETL Tools

ETL testers are required for testing both the tools and the test-cases. This involves the below listed operations −

• Testing the ETL tool and its functions
• Testing the ETL Data Warehouse system
• Create, design, and execute the test plans and test cases.
• Test the flat file data transfers.