Verified Expert in Engineering
Having spent over two decades working on increasingly complex projects—often as a tech lead for large (100+) teams—in healthcare, government, finance, hospitality, and manufacturing, Leonid is a software developer who can build products. Drawing upon his expertise in database development and optimization, he can handle critical tasks such as data processing performance bottlenecks, cross-platform processes/data migrations, and process design.
Linux, Windows, Microsoft SQL Server, Oracle RDBMS
The most amazing...
...thing moving a large operational datastore from Microsoft SQL Server 2008 to Oracle 11; migrating from Oracle 10 on Windows to Oracle 12 on Linux.
Senior Application Analyst
- Implemented highly performant data processing.
- Conducted third-party architectural reviews.
- Performed third-party code reviews and analyses.
- Built the system architecture.
- Ensured data security.
Contract DBA (Oracle and Microsoft SQL Server)
- Optimized the code for Oracle implementations supporting the client's internal and third-party process.
- Optimized the code for Microsoft SQL Server implementations supporting the client's internal and third-party process.
- Provided code reviews and improvement recommendations to the teams.
- Implemented code to automate Oracle database maintenance processes.
- Developed recommendations for next step performance troubleshooting steps.
Senior Software Development Specialist
- Developed and configured software tasks based on operational requirements in an Agile project/development environment using a legacy system.
- Optimized the database process.
- Shared my database expertise with the development team.
- Moved the legacy reports/code from SQL Server 2008 to Oracle 18c.
- Composed system documentation.
- Mentored the junior staff.
Database Administrator — Consultant
Office of Ohio Secretary of State
- Migrated the core system from Oracle 11gR1 on Windows to 12cR1 on Linux.
- Administered to the Oracle APEX development environment.
- Established the Oracle system migration process and schedule with virtually no downtime.
- Optimized Oracle SQL and PL/SQL code.
- Implemented a payment card validation process using PayPal web services.
- Mentored in-house development and DBA teams.
- Implemented a secure code deployment process.
Development Database Administrator (DBA)
- Designed and configured an Oracle 11g development database.
- Supported a geographically distributed team (100+ on/offshore developers).
- Migrated the core database system from Microsoft SQL Server 2008 into Oracle 11g.
- Built complex views, triggers, and stored procedures in Oracle SQL, PL/SQL in support of the development team.
- Developed an upstream automated database code deployment scripting system.
Exceptional Innovation, LLC
- Found solutions to performance bottlenecks in the front-end (C#.NET) and back-end (Microsoft SQL Server 2008/2014) layers.
- Rectified SQL Server concurrency issues enabling simultaneous read and writes (by redefining process architecture emulating PostgreSQL transaction insulation).
- Resolved external vendor errors in contractually supplied data (in Oracle - remotely).
- Implemented Transact-SQL scripts enabling incremental deployment of functionality with transparent handling of partial/aborted runs.
- Performed Microsoft SQL Server 2008/2014 installation, configuration, and patching.
Application Development Lead
- Ported a legacy Microsoft Access business process to Oracle 10.2.
- Developed a C#.NET data transfer utility with automatic process control and notification.
- Wrote scripts for common Oracle administration tasks and data migration.
- Implemented HTML and XML report generators.
- Contacted the administration and provisioning of department-based oversight for remote Oracle environments.
State of Ohio, Department of Health
- Developed a multiformat data loader (C# & Oracle 8i).
- Implemented ETL process on Oracle 8i.
American Electric Power
- Developed and automated a station design system on Oracle7/8i in Delphi.
Managed Care Software
- Developed an EDI module in Delphi to support HIPAA format (ASCII X12).
- Developed eCommerce (ASCII X12 standard) apps in Delphi 1/4/5.
Database Deployment Scripts
The problem at hand is that when app deployment (be it in .NET, Java, or anything else) requires overwriting/replacing an executable file, deploying the database changes becomes an incremental process that that can't be done by "replacing" the old with new.
This is often a risky part of any production deployment process as losing production data can be irreversible (or—at the very least—requires a complicated recovery process). I'm able to mitigate this issue by implementing progressive incremental testable deployment scripts. In every place, where I've established such a process, it is still in use long after my departure.
Oracle to SQL Server and SQL Server to Oracle Migration Guide - Pt. 2
Oracle to SQL Server and SQL Server to Oracle Migration Guide - Pt. 3
Toad, LINQ to SQL, Visual Studio 2019, Visual Studio, Oracle RAC, Microsoft Visual Studio, IBM Rational, Oracle Application Express (APEX), Cygwin
Agile, Object-oriented Design (OOD), Object-relational Mapping (ORM), Cross-platform, COM+
SQL Server DBA, Oracle DBA, Microsoft SQL Server, Oracle SQL Developer, SQL Server Management Studio, Oracle SQL, Oracle PL/SQL, Oracle 11g, Oracle 12c, Relational Databases, ANSI SQL, SQLite, Oracle RDBMS, PL/SQL, SQL Stored Procedures, Databases
Oracle OEM 12c, Scripting, Oracle Database 18c, Triggers, Enterprise, ASCII, X12, HIPAA Electronic Data Interchange (EDI), Libraries, Web Services
.NET, Windows Presentation Foundation (WPF), ASP, ActiveX, ASP.NET, ADO.NET, .NET Core
Oracle, Eclipse, Windows, Linux, Unix, Visual Studio Code (VS Code)
Master's Degree in Chemical Engineering
Petroleum Academy - Moscow, Russia
Certified Delphi 6 Developer