Senior Data Analyst

Job Title

Senior Data Analyst

McLean, VA
Local candidates only – no relocation

Onsite

W2 Contract Only
Long-term contract (~19 months, possible direct opportunities)

$55–65/Hr W2

We are seeking a Senior Data Analyst to support advanced transaction data analysis and merchant attribution efforts. This role focuses on analyzing large volumes of raw card transaction data, developing complex pattern-matching logic, and ensuring high-precision merchant mapping through data-driven rule creation and validation. The ideal candidate is highly analytical, detail-oriented, and experienced in SQL-based analysis and unstructured data parsing.

• Analyze raw card transaction data to identify transaction patterns, noise, and merchant-specific identifiers across eligible merchants
• Develop and maintain complex Regex patterns and rule-based logic to accurately map unstructured transaction strings to merchant entities
• Use SQL to monitor transaction volumes and performance metrics, identifying anomalies that indicate changes in merchant naming conventions or logic failures
• Perform false-positive impact analysis to ensure mapping logic maintains high precision while preserving transaction coverage
• Document authoritative mapping rules and pattern logic to ensure transparency, maintainability, and team-wide understanding
• Manage quarterly update cycles by analyzing the impact of merchant list changes on existing logic and infrastructure
• Establish and execute repeatable QA validation processes using historical datasets prior to production deployment
• Identify and elevate data integrity issues or inconsistencies in raw transaction feeds that could drive downstream errors
• Conduct root-cause analysis on missing or dropped transactions by querying raw data and refining existing logic as merchant behavior evolves

• Strong experience analyzing large, unstructured datasets
• Advanced SQL skills for data querying, validation, and anomaly detection
• Hands‑on experience writing and maintaining complex Regex logic
• Proven ability to perform detailed data quality analysis and root‑cause investigation
• Strong documentation skills to clearly explain logic, decisions, and outcomes
• Ability to manage multiple work streams and iterative rule updates in a production environment

• Experience working with financial or card transaction data
• Background in merchant data attribution or transaction normalization
• Familiarity with QA validation methodologies for large-scale data environments
• Experience supporting long-term, rule-based data platforms in an enterprise setting