Huyen Chang

Data Analyst with 1.5+ years across banking data governance and e-commerce logistics, currently the data owner for warehouse and last-mile operations at GHN — one of Vietnam's largest delivery companies. I supply the verified numbers that operations managers, HR and the board make decisions on, and automate their delivery: 30 data jobs now run daily without manual intervention, removing the need for a dedicated headcount on a reporting routine that was previously done by hand.

Data Analyst at Giao Hang Nhanh (GHN) Service Joint Stock Company (2025-08 – Present)

Single point of contact for data across operations management, HR and the board. Analyze operational performance across the northern hub network and the nationwide 63-province network. Write and optimize analytical SQL over transaction tables of 3M+ rows/day. Investigate operational anomalies and quantify their impact.

• Single point of contact for data across operations management, HR and the board — handling 20+ data requests per week at peak, translating business questions into SQL on Trino/Iceberg and StarRocks and returning verified figures used in reports submitted to senior leadership.
• Analyze operational performance across the northern hub network and the nationwide 63-province network: inbound/outbound volume, inventory aging, leadtime by stage, delivery success rate, productivity per shift and cost per shipment.
• Write and optimize analytical SQL over transaction tables of 3M+ rows/day, applying partition pruning and semi-join pre-filtering to keep queries inside the platform's 120-second execution limit — turning previously unrunnable requests into routine ones.
• Investigate operational anomalies — backlog spikes, first-delivery failure clusters, shift productivity gaps — identifying the bottleneck stage and quantifying its impact so operations can act.
• Automated the recurring reporting cycle end to end. Previously a manual routine — pull data from the company reporting portal, re-pivot it, screenshot and post to team groups. Now fully automated, removing the need for a dedicated headcount on this work.
• Operate 30 automated data jobs running daily, of which 15+ push scheduled reports and threshold alerts directly into operations team groups via Telegram and the company's internal messaging app — teams receive their numbers without requesting them.
• Build a library of reusable core query templates covering the team's recurring metrics, so new requests are assembled from validated logic instead of written from scratch.
• Develop Python pipelines for data cleaning and transformation — including timesheet conversion and shift-schedule processing implemented as SCD Type 2 across 10 change scenarios.
• Gather reporting requirements from each department and convert them into scheduled data jobs; build Google Apps Script automations to sync Google Sheets files.
• Build dashboards in Metabase, Superset, Looker and Power BI for warehouse managers and operations leads, plus custom HTML/JavaScript dashboards for executive ad-hoc analysis — inventory aging, first-delivery failure, cost analysis, hub volume planning.
• Build internal connectors to the company's BI and data platforms (Metabase, Superset, Data API, Notion, Google Sheets), giving the team programmatic, repeatable data access instead of manual exports.
• Catalog 48 production data jobs (SQL, schedule, owner, purpose) into a shared searchable knowledge base; perform data quality testing, SQL review and query optimization across the reporting layer.

Data Governance Analyst at Tien Phong Commercial Joint Stock Bank (TPBank) (2025-02 – 2025-08)

• Built ETL pipelines in Python for data cleansing, centralized storage and loading into SQL Server, serving multiple business departments.
• Developed stored procedures using bulk insert to load flat files into Raw tables, then transform and load into Transformation tables for reporting; wrote SQL queries and user-defined functions against departmental requirements.
• Used Pentaho (Kettle) to design data flows, schedule daily automated reports, compute metrics per report formulas, and distribute reports via Outlook to relevant departments.
• Developed a Python reconciliation tool checking files between shared drives and SQL Server daily, auto-creating folder structures for new branches.
• Monitored SQL Server Activity Monitor and managed user permissions across server and shared folders; debugged and republished departmental Power BI dashboards with access control.

Bachelor of Management Information Systems in Financial and Accounting Informatics – Academy of Finance (2021 – 2025)