Etl Tester

The Senior ETL Tester/Analyst is responsible for analysing requirements and performing end-to-end quality assurance across data integration, ETL/ELT, data warehouse, and analytics platforms. The role designs and executes test scenarios, validates source-to-target mappings and transformation rules, performs data profiling and reconciliation, and investigates defects using advanced SQL and data-analysis techniques. The position ensures data accuracy, completeness, integrity, traceability, and compliance across the full data lifecycle, including sourcing, ingestion, extraction, transformation, Common Data Model mapping, business review and User Acceptance Testing, publication, and downstream consumption. Working closely with Business Analysts, Developers, Product Owners, data engineers, and business stakeholders, the Senior ETL Tester/Analyst supports Agile delivery, provides clear quality and risk insights, and contributes to reliable product releases.

Key Responsibilities

Analyse business requirements, source-to-target mappings, and ETL design documents to understand data flow and transformation rules.

Develop comprehensive ETL test strategies, test plans, test scenarios, and test cases to validate data extraction, transformation, and loading processes.

Validate data accuracy, completeness, consistency, and integrity across source systems, staging areas, and target databases.

Execute ETL testing, data warehouse testing, data migration testing, and regression testing for complex data integration projects.

Write and execute complex SQL queries to perform data validation, reconciliation, and record-level verification.

Validate business transformation rules, data mappings, aggregations, calculations, and data quality requirements.

Perform source-to-target data validation and identify discrepancies between source and target systems.

Verify data load processes, including full loads, incremental loads, Change Data Capture (CDC), and historical data loads.

Create and maintain automated ETL test scripts using testing and automation tools where applicable.

Investigate, analyse, and document data-related defects, perform root cause analysis, and work closely with ETL developers to resolve issues.

Validate data quality metrics, exception handling, error logging, and reconciliation reports.

Collaborate with Business Analysts, Data Engineers, Developers, and stakeholders to ensure business requirements are accurately implemented.

Perform performance and volume testing to ensure ETL processes can handle large datasets efficiently.

Prepare test execution reports, defect metrics, and quality status updates for project stakeholders.

Ensure compliance with data governance, security, privacy, and regulatory requirements throughout the testing lifecycle.

Key Skills

ETL Testing

Data Warehouse Testing

SQL (Advanced Queries, Joins, CTEs, Stored Procedures)

Informatica, SSIS, DataStage, Talend, Azure Data Factory

Data Validation & Reconciliation

Defect Management (JIRA, Azure DevOps)

ETL Automation Testing

Data Migration Testing

Agile & Scrum Methodologies

Power BI / Reporting Validation

Hands-on experience with Azure Data Factory (ADF), Databricks, Delta Lake, and Spark/PySpark ecosystems.

Knowledge of Python, PyTest, REST API testing, CI/CD pipelines, and automated data validation frameworks.

Familiarity with monitoring, observability, and data quality tools used within modern analytics platforms.