Roles and Responsibilities of an ETL Tester.

ETL testers are basically responsible for validating sources data, extracting data, transformation logic application, and loading data into target tables.

Deep knowledge of ETL tools and processes.

Perform thorough testing of your ETL software.

Review the data warehouse test components.

Run data-driven backend tests.

Design and execute test cases, test plans, test environments, etc.

Identify problems and suggest optimal solutions.

Review and approve requirements and design specifications.

Create SQL queries for test scenarios.

Need to perform different types of tests like testing primary keys, default values, and other her ETL related functions.

Regular data quality inspections.

Process of ETL Testing:

Business Requirements Analysis: Design data models, define business flows, and assess reporting needs based on customer expectations. It's important to start here so that the scope of the project is clearly defined, documented, and fully understood by testers.

Data Source validation: To proceed, you must identify your source data and perform preliminary checks such as schema check, number of tables, and table validation. This is to ensure that the ETL process is consistent with the business model specification.

Design Test Cases: Mapping cases to designed in ETL, write SQL scripts, and define transformation rules. It is also important to validate your mapping document to ensure it contains all the required information.

Extract data from source systems: Perform ETL tests as per business requirements. Identify and report on the types of errors and defects encountered during testing. It is important to identify and reproduce the bug, report and fix the bug, and close the bug report before proceeding to other phase

Running a test with error reporting and closure of case: Process of testing goes till the exit criteria (business requirements) are met. If defects were found in the previous step, they were sent to the developer for fixing, and then new tests were run. Additionally, while fixing previous bugs, regression testing is performed to prevent the introduction of new bugs.

Report Summary: Explore the overview report layout, options, filters, and export features. This report informs decision makers and other stakeholders about the details and results of the testing process. If a step was not completed, the reason will be displayed in the report.

Closure of Testing: End of file test. User can proceed with ETL knowing that the data quality is stable.