Oleksandr Vasylenko, Developer in Kyiv, Ukraine
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Oleksandr Vasylenko

Verified Expert  in Engineering

Data Modeling Developer

Location
Kyiv, Ukraine
Toptal Member Since
June 18, 2020

Alex has over 15 years of database development experience working in various roles (ETL, business intelligence, analyst) in large corporate data warehouse projects. Over the course of his career, he has developed strong analytical skills and the ability to get necessary data from any data source in any required form.

OracleSQLQlikViewOracle Business Intelligence Enterprise Edition 11g (OBIEE)Oracle VM VirtualBoxLinuxPL/SQLMacOSAgileShellPythonPostgreSQLScrumTeradataBash

Portfolio

Xenial
Amazon Web Services (AWS), SQL, Python, Redshift, Amazon S3 (AWS S3), MongoDB
Citigroup
uDeploy, SQL, Oracle Database, SAP BusinessObjects Data Service (BODS), QlikView
Oracle
VirtualBox, SQL, Oracle...

Experience

Oracle - 15 yearsData Modeling - 15 yearsDatabase Modeling - 15 yearsSQL - 15 yearsSAP BusinessObjects (BO) - 10 yearsQlikView - 4 yearsOracle Business Intelligence Enterprise Edition 11g (OBIEE) - 3 years

Availability

Part-time

Preferred Environment

GitHub, Visual Studio Code (VS Code), SQL

The most amazing...

...thing I've coded was a mathematical model to build a social network simcard to determine churn possibility & distinguish alpha leaders for marketing promotions.

Work Experience

Big Data Architect

2018 - PRESENT
Xenial
  • Designed, developed, and optimized data warehouses.
  • Worked on the full cycle of ETL; including development and performance optimization and custom data transformation.
  • Architected database designs.
  • Wrote business reports and developed dashboards.
  • Trained, mentored, and implemented best-practice policies for the team.
Technologies: Amazon Web Services (AWS), SQL, Python, Redshift, Amazon S3 (AWS S3), MongoDB

Senior QlikView Developer

2014 - 2018
Citigroup
  • Developed QlikView dashboards as part of a larger effort with a team using Scrum methodology.
  • Spearheaded requirements analysis.
  • Built QVD feeds.
  • Created data models and visualizations.
  • Provided thorough documentation for solutions and processes as well as implemented data quality assurance.
Technologies: uDeploy, SQL, Oracle Database, SAP BusinessObjects Data Service (BODS), QlikView

Senior BI Presale Developer

2011 - 2014
Oracle
  • Provided technical support for presale activities.
  • Developed and demonstrated various types of proof of concept (POC).
  • Created customer presentations and demonstrated the products while attending forums and conferences.
  • Developed and conducted workshops and trainings.
Technologies: VirtualBox, SQL, Oracle, Oracle Business Intelligence Enterprise Edition 11g (OBIEE)

Database Developer

2010 - 2011
Teradata
  • Implemented a social network activity project.
  • Created technical specification designs.
  • Wrote solution documentation.
  • Designed and verified ETL scripts.
Technologies: Teradata, Oracle Data Integrator (ODI), PL/SQL, SQL

BI Architect

2008 - 2010
Teradata
  • Implemented data warehouses.
  • Created BI architecture designs.
  • Built data models.
  • Designed and developed a business objects universe.
  • Developed web reports.
  • Planned and reviewed tasks.
Technologies: Teradata, SQL, SAP BusinessObjects (BO)

BI Developer

2007 - 2008
Teradata
  • Implemented data warehouses.
  • Conducted requirements analyses.
  • Designed the technical specifications.
  • Tracked and fixed bugs.
  • Wrote solution documentation.
  • Created data models.
Technologies: Teradata, SQL, SAP BusinessObjects (BO)

Freelance Engineer

2005 - 2007
Freelance Work
  • Provided data for analytical departments.
  • Gathered user requirements.
  • Developed reports.
  • Worked with billing statistics.
  • Created data models.
  • Implemented SQL tuning and developed with PL/SQL.
Technologies: Oracle Database, HTML, PL/SQL, SQL

Database Developer

2003 - 2005
Citia BTC
  • Implemented an automated budgeting system for the bank.
  • Implemented a mathematical model.
  • Worked on database development.
  • Designed ETL scripts and specifications.
Technologies: Oracle Database, SAP BusinessObjects Data Service (BODS), Oracle, Oracle Application Express (APEX)

QlikView Monitoring Dashboard

A dashboard which enables the user to monitor the reload status of a number of other QlikView dashboards. It needed to be able to crawl by the folder structure to find the logs for each of located dashboards, parse them, and store the gathered data in an internal database. The dashboard also provided info visualizations on the statuses and found errors for each dashboard for the whole monitoring period.

Languages

SQL, Bash Script, Python, Bash, C#, C#.NET, HTML, CSS

Tools

Oracle Business Intelligence Enterprise Edition 11g (OBIEE), Shell, GitHub, VirtualBox, uDeploy, Oracle Application Express (APEX), Amazon Elastic Container Service (Amazon ECS), Tableau

Platforms

Oracle, QlikView, Linux, MacOS, Visual Studio Code (VS Code), Oracle Data Integrator (ODI), Oracle Database, Amazon Web Services (AWS)

Storage

Database Modeling, PostgreSQL, PL/SQL, Amazon S3 (AWS S3), MongoDB, Teradata, Redshift

Other

SAP BusinessObjects (BO), Data Modeling, Shell Scripting, Oracle VM VirtualBox, SAP BusinessObjects Data Service (BODS)

Paradigms

Agile, Scrum, Kanban, REST

Frameworks

.NET

Libraries/APIs

API Development

2004 - 2006

Master's Degree in Applied Mathematics

National Technical University of Ukraine “Kyiv Polytechnic Institute” - Kyiv, Ukraine

2000 - 2004

Bachelor's Degree in Applied Mathematics

National Technical University of Ukraine “Kyiv Polytechnic Institute” - Kyiv, Ukraine