Mihail Ahremenko

Experience

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  Rosbank

  Oct 2008 - Apr 2013

  Domain: Retail Business (Loans).In addition:- help accounting directors to make reports;- help other accountants. Domain: Retail Business (Loans).- DBMS: MS Access;- Reports: Excel;- PL: VBA, VBScript;- Other: IBM System i, AS/400, MS Excel, whole bank's accounting stuff, russian accounting standards, statements, postings, transactions, financial analysis.In first 3 months the 1500 pages book of programming in VBA was thoroughly studied for the purpose of automation our bookkeeping routine (after that, ~80 bookkeepers and accountants relaxed a little). Domain: Retail Business (Loans).Calls, collect debt, consulting.Taken an award "Best hardworker in 2010" (most quantity of calls in the whole Call center).

  • Lead Accountant

    Apr 2012 - Apr 2013

  • Accountant

    Aug 2011 - Apr 2012

  • Collections Specialist

    Oct 2008 - Aug 2011
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  Alfa-Bank

  Apr 2013 - Sept 2014

  Senior Data Analyst

  Domain: Finance of Retail Business (Loans).- DBMS: MS SQL Server;- ETL: SSIS, DTS (for 2008 ver. of MSSQL);- Reports: SSAS (multidimensional OLAP cubes), Excel, Crystal Reports;- PL: SQL, T-SQL, VBA, VBScript;- Infrastructure administration: partial responsibility of MSSQL Server infrastructure (DWH server, SSAS, SSIS);- Data warehouse architecture: Kimball (snowflake scheme);- Other: system / business / financial analysis, financial modelling.Created a big olap-cube for the Legal entities sales department. Show less

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  Bank Otkritie Financial Corporation

  Sept 2014 - Jul 2020

  Domain: ITSM and HR.- DBMS: PostgreSQL, Oracle, MS SQL Server;- ETL: db links (pl/sql scripts, t-sql scripts), powershell, SSIS, Pentaho DI;- Reports: SSRS, SSAS (multidimensional OLAP cubes), Power BI, Excel;- PL: sql, powershell, python, c#, jscript;- Infrastructure administration: full ownership of MSSQL Server infrastructure (DWH, SSRS, SSAS, Power BI, SSIS servers), help with PostgreSQL OLTP servers;- Data warehouse architecture: mixed Data Vault and Kimball and Inmon (snowflake schemes);- Other: data modeling, people managment, interviewing, training, business analysis.Team size: 3 people.SQL query sizes reached 3000 lines.DB Sizes: OLTP PostgreSQL -> Oracle (DB of ITSM system OTRS) ~2 tb, DWH MS SQL ~300 gb.DB users count: DB OTRS ~500, MSSQL ~50, portal SSRS ~200, SSAS (olap cubes) ~50.DB load: DB OTRS ~1000 transactions/sec (OLTP), MSSQL ~2 jobs/sec (DWH).900+ report were created, revised and maintained.Almost 2000 IT guys from the bank started to receive bonuses because some BI system was developed by me.ITSM system "OTRS" database (oltp) was successfully migrated from PostgreSQL to Oracle (for testing, because the OTRS Company could refuse to support PostgreSQL). Show less Domain: Accounting, Finance and Compliance.Project inside the bank Trust (a part of the Financial Corporation).- DBMS: Oracle;- ETL: PL/SQL scripts, Informatica;- Reports: Excel, Oracle ApEx;- PL: sql, pl/sql, vba, vbscript, jsscript;- Infrastructure administration: partial administration of the Oracle DWH server;- Data warehouse architecture: Data Vault;- Other: data modeling, sql loader, jscript, vbscript, vba, .bat, jira, SVN, financial / business / system analysis.Team size: 3 people.SQL query sizes reached 5000 lines.DB had 3 layers (operational, normalized operational, detailed). The second and third layers in conception Data Vault (hubs, satellites, links).DB size (on may 2018): ~15 tb;The reporting process was a bit tricky: DWH -> Oracle Application Express -> XML -> MS Excel.Almost all compliance reports (~30) were under my responsibility.It was a turning point when I started to dive deep into sql. Show less Domain: Finance overall.- DBMS: MS SQL Server, Oracle, PostgreSQL, Vertica;- ETL: Oracle DI, SSIS, PL/SQL scripts, T-SQL scripts, powershell;- Reports: SSRS, SSAS (multidimensional OLAP cubes), Excel;- PL: sql, pl/sql, t-sql, powershell, c#;- Infrastructure administration: partial responsibility of MSSQL Server infrastructure (DWH server, SSRS, SSAS);- Data warehouse architecture: Kimball (star scheme);- Other: MS TFS, SAS AML, FIS Collection Systems, DB and BI servers administration (MSSQL DB, SSRS, SSAS);ITSM system "OTRS" database (oltp) was successfully migrated from Oracle to PostgreSQL. Show less Domain: Finance of Retail Business.Project inside the bank Trust (a part of the Financial Corporation).The bank became part of the Corporaion only in 2017, but in fact the chain of shifts of positions can be considered as within the same organization- DBMS: Oracle, MS Access;- ETL: PL/SQL scripts, VBA (on MS Access), vbscript, jscript;- Reports: Excel;- PL: sql, pl/sql, vbscript, jscript, vba;- Infrastructure administration: partial responsibility of the Oracle server (financial DWH);- Data warehouse architecture: Inmon (snowflake scheme);- Other: financial / accounting / budget / system / business analysis, financial modelling.Automated whole the Collection debts reporting process. Show less

  • Principal BI Developer

    Jul 2018 - Jul 2020

  • Head of DWH Development Division

    Jul 2017 - Jul 2018

  • Data Quality Engineer

    May 2016 - Jun 2017

  • Financial Analyst

    Sept 2014 - May 2016
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  Innotech

  Jul 2020 - Nov 2021

  Lead Data Engineer

  Domain: Treasury and Asset/Liability Management.Project in the Top 2 Russian Bank VTB.- DBMS: Hadoop (Impala, HDFS + parquets);- ETL: spark, sql, Airflow;- Reports: Excel;- PL: python, sql;- DevOps: git, bitbucket, docker, SonarQube, Nexus, TeamCity;- Data warehouse architecture: mixed Data Vault and Kimball (star scheme);- Other: data modeling, Hadoop (HDFS, Yarn, Hue), jupiter notebook, Informatica DQ/Axon, oracle data modeler, jira, confluence.Creating ALM (asset and liability management) DWH for the dynamic balance calculation of VTB bank (stakeholders: Finance, Treasury and Risks): collect business requirements, create DB models (conceptual, logical, physical), DWH/BI development.DWH on Hadoop (for bank's Treasury, with a size of 64 tb) was built from scratch to MVP. Show less

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  E-Global Trade & Finance Group, Inc

  Nov 2021 - Oct 2024

  DWH & BI Developer

  Domain: Trading.- DBMS: Vertica, Clickhouse, Hadoop (HDFS + parquets, deltalake);- ETL: Pentaho DI, python, sql, spark, Airflow;- Reports: Oracle BI, Metabase, Excel;- PL: sql, python, bash/shell;- DevOps: git, bitbucket, docker, Jenkins;- Infrastructure administration: Vertica DWH server, Hadoop cluster, Airflow instance;- Data warehouse architecture: Inmon (star scheme);- Other: software architecture, Trino, linux, jira, confluence.The DWH & BI team is pretty small (compared to my previous experience in banking) - just two people, and we do everything about data: communications with business customers from different countries, business and systems analysis, infrastructure, choosing technologies, developing ETL, building DWH, making reports in BI systems, support, testing, data quality issues, servers' administration.Reduced the ETL time by half, moved DWH from Vertica to Clickhouse, implemented Metabase. Show less

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  Vena Solutions

  Jul 2023 - now

  Lead Data Engineering Consultant

  Domain: FP&A (financial planning and analysis).Implementing Vena Solution products (finance planning and analysis) in a list of small-mid size US companies from the vendor's side.My role is to advise and implement some features in databases and ETL processes on the MS stack.- DBMS: MS SQL Server;- ETL: SSIS, t-sql;- PL: sql, t-sql, python, .bat-scripting, powershell;- DevOps: git, bitbucket;- Infrastructure administration: MS SQL Server;- Data warehouse architecture: Kimball (star scheme). Show less