Publication
Oracle to SQL Server and SQL Server to Oracle Migration Guide
https://www.toptal.com/sql/oracle-sql-server-differences
Leonid is available for hire
Hire LeonidLeonid Draginsky
Verified Expert in Engineering
Software Developer
Location
Westerville, OH, United States
Toptal Member Since
June 18, 2020
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.
Portfolio
Fiserv
Python, Java, Databases, C#.NET
Anthem, Inc.
Stored Procedure, SQL Stored Procedures, Oracle PL/SQL, Oracle SQL...
Sedgwick CMS
Visual Studio, C#.NET, Cross-platform, Triggers, PL/SQL, SQL...
Experience
Availability
Part-time
Preferred Environment
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.
Work Experience
Senior Application Analyst
2020 - PRESENT
Fiserv
- Implemented highly performant data processing.
- Conducted third-party architectural reviews.
- Performed third-party code reviews and analyses.
- Built the system architecture.
- Ensured data security.
Technologies: Python, Java, Databases, C#.NET
Contract DBA (Oracle and Microsoft SQL Server)
2019 - 2020
Anthem, Inc.
- 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.
Technologies: Stored Procedure, SQL Stored Procedures, Oracle PL/SQL, Oracle SQL, Microsoft SQL Server, Oracle 12c
Senior Software Development Specialist
2016 - 2019
Sedgwick CMS
- 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.
Technologies: Visual Studio, C#.NET, Cross-platform, Triggers, PL/SQL, SQL, Microsoft SQL Server, Oracle Database 18c
Database Administrator — Consultant
2015 - 2016
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.
Technologies: Cygwin, Oracle SQL Developer, Toad, Microsoft SQL Server, Oracle Application Express (APEX), Oracle RAC, Oracle, SQL, Oracle SQL, Oracle 11g
Development Database Administrator (DBA)
2012 - 2015
JPMorgan Chase
- 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.
Technologies: Oracle RAC, T-SQL (Transact-SQL), SQL Stored Procedures, Oracle PL/SQL, Oracle SQL, Microsoft SQL Server, Oracle 11g
Software Developer
2010 - 2012
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.
Technologies: Microsoft SQL Server, T-SQL (Transact-SQL), SQL, Web Services, Windows Presentation Foundation (WPF), ASP.NET, ADO.NET, LINQ to SQL, LINQ, Microsoft Visual Studio, C#.NET
Application Development Lead
2004 - 2010
JPMorgan Chase
- 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.
Technologies: Java, XML, HTML, Oracle SQL, Eclipse, IBM Rational, Visual Studio, ASP.NET, C#.NET, Toad, Oracle PL/SQL, SQL
Programmer/Analyst 4
2002 - 2004
State of Ohio, Department of Health
- Developed a multiformat data loader (C# & Oracle 8i).
- Implemented ETL process on Oracle 8i.
Technologies: Delphi, ActiveX, COM+, JavaScript, Java, ASP, ASP.NET, XML, HTML, .NET, Visual Studio, C#.NET, Toad, SQL, Oracle PL/SQL
Delphi Programmer
2001 - 2002
American Electric Power
- Developed and automated a station design system on Oracle7/8i in Delphi.
Technologies: Oracle PL/SQL, SQL, ActiveX, Libraries, Delphi
Software Engineer
2000 - 2001
Managed Care Software
- Developed an EDI module in Delphi to support HIPAA format (ASCII X12).
Technologies: HIPAA Electronic Data Interchange (EDI), X12, ASCII, Enterprise, Delphi
Software Engineer
1998 - 2000
EDICT Systems
- Developed eCommerce (ASCII X12 standard) apps in Delphi 1/4/5.
Technologies: HIPAA Electronic Data Interchange (EDI), X12, ASCII, Delphi
Experience
Database Deployment Scripts
When functioning as a database administrator—whenever it's my sole responsibility or in addition to my core development functions—I'm always implementing scripting containers that allow database code upstream deployment to be "non-event."
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.
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.
Skills
Languages
SQL, T-SQL (Transact-SQL), C#.NET, Java, Python 3, HTML, XML, JavaScript, Stored Procedure, Python, Delphi, Python 2
Libraries/APIs
LINQ
Tools
Toad, LINQ to SQL, Visual Studio 2019, Visual Studio, Oracle RAC, Microsoft Visual Studio, IBM Rational, Oracle Application Express (APEX), Cygwin
Paradigms
Agile, Object-oriented Design (OOD), Object-relational Mapping (ORM), Cross-platform, COM+
Storage
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
Other
Oracle OEM 12c, Scripting, Oracle Database 18c, Triggers, Enterprise, ASCII, X12, HIPAA Electronic Data Interchange (EDI), Libraries, Web Services
Frameworks
.NET, Windows Presentation Foundation (WPF), ASP, ActiveX, ASP.NET, ADO.NET, .NET Core
Platforms
Oracle, Eclipse, Windows, Linux, Unix, Visual Studio Code (VS Code)
Education
1979 - 1984
Master's Degree in Chemical Engineering
Petroleum Academy - Moscow, Russia
Certifications
FEBRUARY 2002 - JANUARY 2004
Certified Delphi 6 Developer
Brainbench