Data Warehouse (DWH) / ETL Test Engineer

Overview:

We are seeking a highly motivated and skilled Data Warehouse (DWH) / ETL Test Engineer with 3 to 6 years of experience to join our data team. The successful candidate will be responsible for ensuring the accuracy, completeness, and integrity of data flowing through our Extract, Transform, Load (ETL) pipelines and residing in our enterprise Data Warehouse. This role requires expertise in complex SQL queries, a strong understanding of dimensional modeling, and a commitment to data quality assurance.

Key Responsibilities

Test Strategy & Design: Design, develop, and execute detailed test plans and test cases for ETL processes, data migrations, and DWH reports/dashboards.
Data Validation: Perform comprehensive data validation and reconciliation between source systems, staging areas, and the target data warehouse/data marts.
Complex SQL Querying: Write and execute complex SQL queries (including multi-table joins, subqueries, and aggregate functions) to validate data transformations and business rules.
DWH Testing: Verify data modeling (star, snowflake schemas), fact and dimension table loading, historical data maintenance, and slowly changing dimensions (SCDs).
Pipeline & Tool Testing: Test data flow across various ETL tools and technologies (on-premise or cloud-native services).
Performance Testing: Execute tests to validate ETL job execution performance, ensuring data loads meet defined service level agreements (SLAs).
Defect Management: Identify, log, track, and retest defects using defect management tools (e.g., JIRA, Azure DevOps, ALM) and communicate status updates clearly to stakeholders.
Collaboration: Work closely with ETL Developers, Data Architects, Business Analysts, and BI teams to understand requirements and resolve data quality issues.

Required Qualifications (3-6 Years)

Experience: 3-6 years of professional experience dedicated to Data Warehouse (DWH) and ETL testing.
SQL Mastery: Expert-level proficiency in writing and troubleshooting complex SQL queries for data comparison, validation, and manipulation.
DWH Fundamentals: Strong conceptual knowledge of Data Warehousing principles, including dimensional modeling, schemas (star and snowflake), OLAP/OLTP concepts, and data mart design.
ETL Testing Lifecycle: Proven experience in the full software testing lifecycle (STLC) specific to data projects, including requirement analysis, test planning, execution, and reporting.
Tooling: Hands-on experience with at least one major ETL tool (e.g., Informatica PowerCenter, Talend, DataStage) OR cloud-native ETL services (e.g., AWS Glue, Azure Data Factory, or GCP Dataflow/Cloud Composer).
Communication: Excellent written and verbal communication skills, with the ability to explain technical issues to both technical and non-technical audiences.