Profileimage by Stefan Corsten Senior Consultant BI, DWH, ETL, Reporting, Informatica, Teradata from Wegberg

Stefan Corsten

not available until 01/03/2022

Last update: 10.09.2021

Senior Consultant BI, DWH, ETL, Reporting, Informatica, Teradata

Company: Corsten
Graduation: not provided
Hourly-/Daily rates: show
verhandelbar, je nach Tätigkeit und Einsatzort
Languages: German (Native or Bilingual) | English (Limited professional) | Portuguese (Full Professional)


Databases Microsoft SQL-Server Windows Reporting Oracle Data Integrator 12c Cognos DWH Powerplay Data Analyst Visual Basic Senior ETL Entwickler SAS Base .NET VBA Oracle 11g ETL (Informatica Powercenter) XML Microsoft SQL-Server SSAS SEM SEO Google Adwords Microsoft Office + Visio English Portuguese German Microsoft SQL-Server SSRS SEA Teradata SQL SSIS Unix




Education / Training
2000 – 2001             Training for developer C/C++ and VB 6 as well as Network Administrator with Windows 2000 Systems.
2001                         Java Training
2002                         Administration of Linux – Servers
2013                         Training: Cognos Reporting Studio 10.1 and Cognos Query Studio 10.1
2014                         Training MongoDB (1 day only)
2014 – 2016             Distance learning course: information scientist
                                 Course contents:
  • Numerical systems and manner of operation of computers
  • Introduction in C++ decisions and loops
  • Statistic data compression cryptography and set theory
  • From Boolean logic to switching circuits, automates and machines.
  • Introduction in software engineering and UML
  • Object oriented programming using C#, inheritance and polymorphism. Programming objects: browser, word processor, library administration program.
  • Database development using MySQL and PHP. Database theory and programming
  • Installation of virtual machines using VMWare
  • Networks with Windows Server 2012: net cards and topologies, TCP/IP
  • Programming of robots: Sensors, remote control via Bluetooth
  • AI: State of research, search algorithms and neural networks.
2015                         Microsoft certifications:
                                 08/15        MOC 70-461:
                 Querying Microsoft SQL Server 2012
                                 09/15        MOC 70-462:
                 Administering Microsoft SQL Server 2012   Databases
                                 10/15        MOC 70-463:
                 Implementing a Data Warehouse with          Microsoft SQL Server 2015
                                 10/15       MCSA SQL Server 2012
2015 – now            correspondence course at EuroFH in IT-Management. Expected degree: Bachelor of Science

PC- and Hardware – Systems
Windows 95 / 98 / Me
Windows NT (all versions, Server and Client)
Windows 2000 (all versions, Server and Client)
Windows XP
Windows Vista (all versions)
Windows 7 (all versions)
Windows 8, Windows 8.1, Windows 10
Windows Server 2003 - 2012
Linux / Unix
Database- and Development – Tools
DBase IV for MS – Dos
MS – Access
MS – SQL-Server 2000 - 2016
MS – Analysis – Services (SSAS) 2000 – 2016
MS – Reporting –Services (SSRS) 2005 - 2016
MS – Integration – Services (SSIS) 2005 - 2016
Oracle 8 - 11
Informatica Powercenter 8.6.1 Hotfix 12
Informatica Powercenter 9.1.0 Hotfix 2
Cognos Powerplay
Cognos Reporting Studio 10.1
Cognos Query Studio 10.1
Visual Studio 2005 - 2016
Programming Languages
Transact – SQL
C / C++ / C#
Basic (Visual Basic.NET 2003 - 2010 / Visual Basic 6.0,/ Quick Basic / VBA / VB Script)
.NET – Framework
Pascal (Turbo Pascal 6.0 / Delphi 5.0)
UNIX – Shell Scripts
Java (Basics)
Standard Software
MS-Office 97 – 2013 (including VB/VBA – Development)
MS Viso
Language skills
German                    maiden language
English                     fluent
Portuguese               fluent

Project history

04/2017 - Present
DWH – development and reporting

Development of SSIS packages to exchange data between different systems in the fields of personal and job management and development of complex reports using SSRS

  • Read data from the source systems
  • Transform data to be accepted by the destination systems
  • Provisioning of data for the destination systems
  • Design of complex reports for finance and controlling


Development of a new reporting system, using Power-BI in a SSAS tabular model and report the data, using Microsoft Reporting-Services

  • Design and construction of a new DWH, including a staging area, using TSQL scripts and SQL-Server agent
  • Design and construction of the tabular model
  • Development of the reports
  • Acquire data for the reports, using DAX-queries


          Used Tools:

    • Microsoft SQL-Server 2016
    • SSIS 2016
    • SSRS 2016
    • SSAS 2016
    • Power-BI
    • DAX
    • SQL / T-SQL
    • Stored Procedures
    • Visual Studio 2015 und 2017

05/2019 - 08/2019
DWH – development
Delticom AG

Development of SSIS packages to exchange data between different systems. Development of functions and procedures as well as methods for table partitioning.

  • Development and bug fixing of SSIS packages
  • Development and bug fixing of functions and procedures
  • Implementation of SCD2
  • Implementation of table partitioning, including automatic extension of the partition functions
  • Documentation


          Used Tools:

    • Microsoft SQL-Server 2016
    • SSIS 2016
    • SSRS 2016
    • SQL / T-SQL
    • Stored Procedures
    • Visual Studio 2015 und 2017
    • GIT
    • Jira
    • Confluence

08/2017 - 04/2019
SQL-Server development
Softwarekontor / BASF

An existing application for effectivity analysis should be replaced by a new one. Therefor the existing data has to be migrated into the new application. Both applications are individually developed by Softwarekontor. The old application is based on Java and Oracle while the new one is based on .Net and SQL-Server 2016.

  • Data analysis of the old application system
  • Development of procedures to extract data from the old system
  • Development of routines to transform data.
  • Development of procedures to load the data into the new database.
  • Integrate the procedures into SSIS packages.
  • Development of procedures to be called by the client application.
  • Reproduction of the data preparation for the reporting.
  • Automated generation of standard objects (procedures, views, etc.) using T4 templates.

          Used Tools:

    • Microsoft SQL-Server 2016
    • Oracle 11.2 g
    • SQL Developer 4.0.2
    • SSIS 2016
    • SQL / T-SQL
    • XML
    • Stored Procedures
    • User Defined Functions
    • Tangible T4 
    • Visual Studio 2015

07/2016 - 07/2017
DWH – Development and Microsoft Dynamics CRM
Defacto Realations / Hugo Boss

Development and bug fixing of SSIS packages for data load into the CRM system as well as data selection and enrichment to be used for marketing campaigns.

  • Development and bug fixing of SSIS packages for data selections used for marketing campaigns.
  • Further development of SSIS packages for data import into the CRM system.
  • Further development of SSIS packages for data exchange in  CSV or XML format. 
  • Further development and bug fixing of SSIS packages used for data exchange between CRM and other systems like SAP (e.g. up- and downstream of contact data)

Used Tools:

    • Microsoft SQL-Server 2012
    • Microsoft SQL-Server 2014
    • Microsoft Dynamics CRM 4.0
    • Microsoft Dynamics CRM 2015
    • SQL / T-SQL
    • Stored Procedures
    • C# 
    • .Net Framework

07/2016 - 03/2017
DWH – Development with Teradata and Informatica

Transfer of processes from development into a quasi-productive pilot environment, build up a maintenance environment and further development of quality assurance systems.

          Used Tools:

    • Teradata
    • SQL Assistant
    • Informatica Power Center Designer 9.1.0 Hotfix 2
    • Informatica Power Center Workflow Manager 9.1.0
    • Informatica Power Center Workflow Monitor 9.1.0
    • SQL / PL-SQL  
    • AIX / UNIX / KSH / Bash
    • Putty
    • WinSCP
    • FTP
    • BTEQ

01/2016 - 07/2016
DWH – Data migration (Area Life)
R+V Insurances

Migration of insurance contracts from CONDOR – Insurances in Hamburg into the data pool of the R + V – Insurances. Contracts had to be migrated as well from Client/Server systems as from the HOST.

  • Analysis of PL/1 – Copybooks and their corresponding data files from the source system.
  • Analysis of the COBOL – Copybooks of the destination system.
  • Development of a solution to process the PL/1 data automatically under consideration of the copybooks using C#. The solution transforms the copybooks into XML files, which describes the structure of the data files from the HOST and uses them to load and cut the data files which are delivered as flat files with fixed length format. In a first step one HOST file will be separated into multiple CSV files, which each contain one HOST segment. The solution will also take care of the OCCURS structures.
  • Data processing, data import and export.
  • Development of generators to automatically build stored procedures, which are uses for the mappings and data load into the SQL Server.

          Used Tools:

    • Microsoft SQL-Server 2012
    • Microsoft SQL-Server 2014
    • DDL
    • SQL / T-SQL
    • Stored Procedures
    • C# 
    • .Net Framework
    • MVVM
    • TPL Dataflow
    • XQuery
    • Linq to XML

10/2015 - 03/2016
DWH Development

Development of extract and load routines by using shell scripts, fast load – files and C – functions 

  • Loading of flat files, delivered from GKV (statutory health insurance) into the DWH. The files primarily contain billing data of the single health insurances. Those data will be stored into the centralized DWH of the GKV (statutory health insurance). 
  • Adaption and integration of the ETL processes.
  • Extract the dates that have been reprocessed for the specific health insurances into flat files as well.
  • Documentation  of the request and the implementation
  • Design, execution and documentation of test cases and their results.

Used Tools:

    • Unix
    • Bash
    • AWK
    • SED
    • Fastload
    • C
    • PuTTY
    • WinSCP
    • Tortoise SVN
    • Teradata Database
    • Teradata Administrator 15.10
    • Teradata SQL Assistant 15.10
    • Teradata Macros
    • DDL
    • SQL / T-SQL

11/2015 - 01/2016
DWH redesign

Review and Redesign of existing DWHs to ascertain customer experience (One CXX)

  • Review of existing documentations
  • Review of existing databases, tables, attributes, entities and constraints
  • Development of an appropriate DWH structure for this task under consideration of the DWH layers.
  • Development of a concept for building a GUI for master data management.

Used Tools:

    • Sybase PowerDesigner 16.5
    • Microsoft SQL-Server 2015
    • DDL
    • SQL / T-SQL

01/2014 - 12/2015
DWH Development

Adaption from a campaign management tool that was designed for the parent company, named HRS. Redesign of the ETL processes and destination tables to match the business logic from This also includes as well as bug fixing as implementing new KPIs. Everything has been done with a close reconcilement to the marketing department.  

  • Analysis of existing ETL – processes, business processes and KPIs.
  • Adaption of database structures to the current operational facts and business processes. 
  • Adaption and integration of the ETL processes.
  • Further development of existing ETL processes for higher performance and stabilization of the daily loads.
  • Adaption and further development of the KPIs.
  • Development of the cube for the reporting, used by marketing department.


Further development of the hotel DWH in the daily business. This includes ad-hoc queries as well as bug fixing and development of new ETL processes.

  • Reverse-engineering of the existing data model.
  • Further development of the data model.
  • Bug fixing of existing ETL processes.
  • Development of new ETL processes.
  • Further development of the operations cube.


Collaboration by the redesign of a new DWH that is needed for performance optimization and restructuring the databases and ETL processes.

  • Analysis of data sources and data consumers.
  • Development of the data model (design and implementation)
  • Development of the ETL processes. 
  • Documentation

          Used Tools:

    • SQL Server 2012 / 2014
    • SSIS 2012 / 2014
    • SSRS 2012 / 2014
    • SSAS 2012 / 2014
    • PowerBI
    • Team Foundation Server
    • Visual Studio 2010 / 2013
    • C# .NET
    • MongoDB
    • SQL / T-SQL / JSON
    • MDX
    • XML / XLST
    • SEM / SEO / SEA
    • WebTrekk
    • Distimo
    • Qonka
    • Dymatrix campaign management tool 
    • Windows 7 / Windows Server 2012R2
    • Sybase Power Designer 16.5

Time and spatial flexibility

I am available from May, 15th 2020 for 100% at client side or remote.
Possible locations: Germany, Europe, South America

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