Olivia Lewis Senior SQL Developer
Boston, MA • sqldev@gmail.com • +1 (617) 555 0488
Profile Summary
- Senior SQL Developer with 9 years of experience building enterprise transactional and analytical SQL platforms across healthcare claims, clinical analytics, and pharmacy operations, specializing in complex T-SQL, query tuning, schema design, and ETL for warehouse loading.
- Hands-on coverage across RDBMS (SQL Server), dialect (T-SQL), ETL (SSIS), BI / reporting (Power BI), and modeling (ER/Studio, Flyway) with strong fundamentals in strong set-based thinking, window functions, recursive CTEs, and execution-plan literacy across multiple dialects.
- Deep expertise in normalized OLTP schema design, star schema and dimensional modeling, indexing and partitioning strategy, and ETL pipeline design into warehouse marts, applying methodologies such as execution-plan-driven tuning with statistics review and set-based rewrites of cursor and loop logic for warehouse-scale workloads to deliver fast, accurate SQL platforms fit for regulated healthcare and enterprise reporting.
- Engaged collaborator working cross-functionally with Analytics, Application, DBA, and Compliance teams in Agile delivery and quarterly release trains, contributing to schema reviews, sprint planning, and query-design walkthroughs with an ownership-first mindset and clean handoffs.
- Mentor who shares technical excellence and fosters a culture of data accuracy and query-review discipline through PR reviews and pattern docs, while running SQL guild and tuning office hours and authoring widely used procedure and reconciliation templates.
Technical Skills
- Databases & Dialects:
- T-SQL, PL/SQL, PL/pgSQL, ANSI SQL, SQL Server, Oracle, PostgreSQL, MySQL, Db2, Python (basic)
- Schema Design & Modeling:
- 3NF normalization, star schema, snowflake schema, OLTP modeling, OLAP modeling, ER/Studio, ERD design, PK/FK design, referential integrity
- Procedural SQL & Objects:
- stored procedures, functions, triggers, packages, cursors, CTEs, window functions, recursive queries, pivots, merge / upsert
- Query Tuning & Indexing:
- execution plans, index strategy, query rewrites, statistics, hints, partitioning, SARGable predicates, covering indexes, columnstore, Query Store
- ETL & Data Integration:
- SSIS, Informatica, Talend, Azure Data Factory, SQL-based ELT, staging / loading, CDC, incremental loads, data warehouse loading
- Reporting & BI:
- Power BI, SSRS, Tableau, Looker, views, materialized views, reusable datasets, KPI rollups, dimensional reporting
- Source Control & Deployment:
- Git, Flyway, Liquibase, Redgate, dbt, Azure DevOps, GitHub Actions, Jenkins, change scripts, DBA collaboration
- Security & Compliance:
- roles and schemas, least-privilege, row-level security, dynamic data masking, TDE, column encryption, auditing, HIPAA / PHI handling, PII redaction
Education
Northeastern
University
B.S. in Computer
Science
Work Experience
CVS Health
Senior SQL
Developer
- Owned complex SQL development and end-to-end delivery on the pharmacy claims and clinical reporting platform handling 38M claims rows / day, writing claims ingestion, rebate reconciliation, and formulary reporting queries across 6 databases on modern SQL Server.
- Designed and evolved schemas in ER/Studio following 3NF OLTP with a star-schema mart, defining PKs, FKs, check constraints, and indexes across 320+ tables with 450+ enforced FK relationships, holding referential integrity through every release.
- Built procedural logic with T-SQL stored procedures, scalar and table-valued functions, and audit triggers, leaning on modular T-SQL with table-valued parameters to consolidate 180+ procs into a shared layer, cutting duplicated business logic across the platform by 46%.
- Tuned slow reports and ingestion paths with execution-plan analysis with statistics refresh and SARGable rewrites, Query Store baselines, and parameter-sniffing fixes across 120+ slow queries, pulling the month-end formulary report runtime from 42 min down to 6 min on the same hardware footprint.
- Drove indexing and physical design with covering and columnstore indexes with monthly partitioning, filegroup placement, and filtered indexes against the SQL Server claims tables, redesigning 85 indexes and trimming logical reads per claims-search batch by 71%.
- Published analytical SQL for Power BI and SSRS dashboards through reusable views and materialized datasets, window-function rollups, and indexed views across 45+ shared datasets, dropping the analyst refresh window during quarter-close by 58%.
- Owned warehouse loading with SSIS packages and SQL-based ELT, with incremental SSIS loads with CDC and watermarks across 32 nightly jobs moving 2.4 TB into the claims mart, cutting the overnight load window by 63%.
Liberty Mutual
SQL
Developer
- Owned data quality and reconciliation across the policy and claims warehouse with reconciliation queries with row-count and hash checks, duplicate-detection CTEs, and orphan-record sweeps across 60+ scheduled validation checks, dropping duplicate policy records reaching downstream BI by 72%.
- Hardened database security and access control with role-based access with row-level security and dynamic data masking, schema-scoped GRANTs, and PII redaction reviews across 22 least-privilege roles, lifting the annual SOX audit and dropping privileged-access findings by 64%.
- Shipped database changes through source control and DBA partnership with versioned Flyway migrations through Azure DevOps pipelines, pre-deploy review gates, and rollback scripts on every change across 80+ production releases, cutting failed deploys traced to DDL or DML scripts by 78%.
- Strengthened core SQL foundations across the team through window functions, recursive CTEs, and pivots, set-based rewrites of cursor logic, and dialect breadth across SQL Server and Oracle, while mentoring 3 junior developers through pair-coding, review checklists, and a written modern-SQL idiom guide.