Sen Mu

Highly accomplished SQL Server / Data Warehouse Developer & Data Engineer with 15+ years of experience delivering enterprise-scale data solutions across financial services, healthcare, and large enterprise environments. Advanced expertise in T-SQL, SQL Server, SSIS, SSAS, SSRS, ETL/ELT pipelines, dimensional modeling, and performance tuning. Strong background in data integration, data migration, and cloud modernization, including Snowflake on AWS, PySpark and Apache Spark.

Known for designing resilient, scalable data architectures; building complex ETL frameworks; optimizing high-volume workloads; and supporting mission-critical production systems. A self-starter with strong analytical skills, excellent communication, and a passion for continuous learning.

SQL Server / ETL & Data Engineer - Wells Fargo - St. Louis, MO

(2019-09 - 2026-04)

• Designed, developed, and optimized high-volume T-SQL stored procedures, table-valued functions, dynamic SQL frameworks, and complex multi-step ETL logic, supporting Market Risk Management and enterprise reporting needs.
• Built and maintained large-scale SSIS frameworks including parameterized packages, parent–child package architectures, custom logging, checkpoint restartability, and automated error-routing pipelines.
• Engineered advanced ETL/ELT pipelines using SSIS, T-SQL, SQL Loader, C#, and batch automation to integrate data from OLTP systems, flat files, XML, JSON, and APIs.
• Developed data validation, reconciliation, encryption, and auditing frameworks using T-SQL window functions, MERGE logic, CDC patterns, and SSIS script components.
• Built SSIS-driven ingestion pipelines with parallel data flows, lookup caching strategies, fuzzy grouping, conditional splits, and script transformations for complex cleansing and enrichment.
• Architect and implement star and snowflake schemas using Kimball methodologies.
• Build and maintain SSAS tabular and multidimensional cubes for enterprise analytics.
• Performed deep performance tuning of stored procedures and T-SQL workloads using execution plans, statistics I/O, indexing strategies, DMVs, SQL Profiler, and IDERA.
• Utilized SQL Server Profiler to trace and diagnose performance bottlenecks, deadlocks, and long-running queries, improving system stability and query efficiency.
• Captured and analyzed real-time SQL Server events using Profiler to troubleshoot production issues and optimize stored procedures and T-SQL workloads.
• Provide Tier-2 production support for SQL Server Agent jobs, replication, SSIS packages, and ETL pipelines.
• Automate deployments using PowerShell, including SSAS cube deployment and SQL script automation.
• Maintain enterprise reporting solutions using SSRS and Power BI.
• Build Azure DevOps pipelines for automated code deployment.
• Lead efforts to modernize the on-premises data warehouse to Snowflake on AWS.
• Design and implement Snowflake data models, warehouses, and compute strategies.
• Build scalable Snowflake ELT pipelines using Snowpipe, Streams, Tasks, and external stages.
• Integrate AWS services including S3, Lambda, Glue, IAM, and event-driven ingestion patterns.
• Optimize Snowflake performance via clustering, micro-partitioning, and query profiling.
• Develop secure data-sharing and role-based access models.
• Build distributed data processing pipelines using PySpark and Apache Spark for large-scale transformations.
• Implement Spark jobs for ingestion, cleansing, enrichment, and aggregation of high-volume datasets.
• Optimize PySpark workloads using partitioning, caching, broadcast joins, and cluster resource tuning.
• Develop reusable PySpark modules for ETL orchestration and data quality frameworks.
• Integrate PySpark pipelines with AWS S3, Glue Catalog, and Snowflake external stages.

SQL Server / ELT Developer - Equifax - St. Louis, MO

(2018-09 - 2019-09)

• Engineered enterprise-grade SSIS ETL pipelines integrating HR, Financial, Payroll, and Accounting data from multiple OLTP systems and interface files.
• Built complex T-SQL stored procedures, triggers, views, and dynamic SQL modules to support data transformations, auditing, and reconciliation across the data warehouse.
• Designed SSIS packages with configurations, parameters, event handlers, custom logging, and error redirection, ensuring resilient and restartable ETL operations.
• Developed data quality and reconciliation frameworks using T-SQL window functions, CROSS APPLY logic, MERGE statements, and SSIS data flow transformations.
• Performed deep performance tuning of T-SQL code using execution plans, DMVs, statistics IO, SQL Profiler, and IDERA.
• Maintained and expanded a large portfolio of SSIS packages supporting enterprise-wide ETL operations.
• Automated SQL Server Agent job chains for nightly ETL cycles, including dependency management, alerting, and failure recovery.
• Served as BI DBA, managing replication, backups/restores, security permissions, and database health monitoring using IDERA.

SQL Database Developer - Motion Industries - Birmingham, AL

(2017-12 - 2018-09)

• Designed and developed SSIS-based ETL pipelines for large-scale ERP data conversion and migration, including cleansing, standardization, and transformation of multi-source datasets.
• Built complex T-SQL scripts, stored procedures, and staging frameworks to transform DB2, Oracle and SQL Server data into unified ERP structures.
• Developed ETL workflows integrating Oracle with SQL Server, DB2, and flat-file sources using SQL Loader, external tables, and custom scripts.
• Implemented data migration and conversion routines using PL/SQL, SQL Loader, and batch automation for large-scale system transitions.
• Automated migration workflows using SQL Server Agent and SSIS, including incremental loads, delta detection, and validation routines.
• Developed data validation and integrity checks using T-SQL, SSIS lookups, conditional splits, and script components to ensure structural and referential accuracy.
• Created reusable SSIS templates for error logging, audit trails, and metadata-driven ETL execution.
• Partnered with project managers and engineers to resolve data integrity issues and optimize database design.

SQL Developer / ETL Developer - BD (Becton Dickinson) - Birmingham, AL

(2013-07 - 2017-12)

• Designed and implemented SSIS ETL pipelines to ingest HL7, pharmacy, lab, surgical, and ADT data feeds into operational and analytical data models.
• Built advanced T-SQL transformation logic including window functions, CROSS APPLY, PIVOT/UNPIVOT, regex-based cleansing, and dynamic SQL for healthcare data normalization.
• Developed C# Windows services and SSIS packages for automated ingestion, validation, and transformation of clinical data.
• Authored T-SQL scripts and reporting queries for clinical implementation teams, including parameterized stored procedures and reusable reporting views.
• Performed advanced query tuning, index optimization, and troubleshooting using execution plans, statistics IO, and SQL Server tools.
• Created and maintained stored procedures, triggers, views, UDFs, table-valued expressions, and temporary objects.
• Managed SQL Server Agent jobs, index maintenance, fragmentation analysis, and performance optimization.

M.S. - Biology (Bioinformatics) - East Tennessee State University (2013)

B.S. - Health Sciences (Health Informatics) - East Tennessee State University (2010)

B.S. - Computer Science & Technology - Shandong Normal University (2012)