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Mirko Marović, Indexing Developer in Prague, Czech Republic
Mirko Marović

Indexing Developer in Prague, Czech Republic

Member since February 19, 2020
Mirko has more than twenty years of experience in database design, development, and optimization. He's had the opportunity to work with the most used database platforms: MS SQL Server, Oracle, MySQL, and PostgreSQL. He optimized database queries, indexes, and settings for databases with the extreme workload. He developed solutions for customers from the USA, Russia, Czech Republic, Germany, Norway, Serbia, and Bosnia.
Mirko is now available for hire
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Portfolio

Experience

Location

Prague, Czech Republic

Availability

Part-time

Preferred Environment

PostgreSQL, MySQL, Oracle, Microsoft SQL Server

The most amazing...

...performance improvement I've achieved was redesigning a query generator accessing tables with billions of rows. I improved performance 12-80 times.

Employment

  • Senior Database Specialist

    2009 - PRESENT
    Self-employed
    • Developed and optimized MySQL query generation patterns for https://spikeet.com/. Improved 12-80 times the performance of queries from the previous version.
    • Developed SQL Server stored procedures and triggers for Faraj Fund, UAE.
    • Built PostgreSQL functions and optimized queries and indexes for TV Nova, Czech Republic.
    • Created the scheduling algorithm, and the database model, and developed MySQL queries for the 3v3 football tournaments portal, Phoniax, Norway.
    • Designed and developed a SQL Server reporting database for Blue Rabbit, DKNY exclusive distributor in Prague, Czech Republic.
    • Designed a POS application for Blue Rabbit, Czech Republic.
    • Developed Oracle PL/SQL packages of data synchronization between provisioning and billing system for MT:S telecom operator, Serbia.
    Technologies: PostgreSQL, MySQL, Oracle, Microsoft SQL Server

  • Quality Assurance Manager

    2007 - 2009
    SitronicsTS, Prague, Czech Republic
    • Managed the quality assurance department, including test analysis, test execution, test automation, test data preparation, integration testing, and performance testing teams.
    • Participated in the design and establishment of SDLC and QA processes.
    • Managed product testing of various telecom OSS/BSS deliveries in Russia, Czech Republic, Germany, Uganda, and Serbia.
    Technologies: TFS, TestComplete, LoadRunner, Microsoft Dynamics CRM, TIBCO, .NET, Oracle 10g

  • Consultant

    2005 - 2006
    Time Import, Prague, Czech Republic
    • Gathered and manage requirements for KUSCK, Czech Republic.
    • Deployed, configured, and managed the subversion version control system.
    • Design high-level architecture of KUSCK customer portal back-end.
    Technologies: Microsoft Project Server, Subversion (SVN), BizTalk

  • Database Engineer

    2003 - 2005
    Tmp Worldwide (Monster), Maynard (USA), Prague Czech Republic
    • Developed stored procedures for a campaign management data mart.
    • Reviewed code and trained more than 40 developers in T-SQL best practices.
    • Designed indexes and optimized stored procedures for job seekers, employers, and mass sender subsystems.
    Technologies: Rational ClearQuest, Embarcadero RAD Studio, Microsoft SQL Server

  • Oracle Consultant

    2003 - 2003
    Ad Astra, Prague, Czech Republic
    • Developed PL/SQL packages implementing Wholesales Billing API for GTS (telecom operator), Czech Republic.
    • Designed the logical and physical model for GTS Wholesales Billing.
    • Introduced unit testing for PL/SQL stored procedures and functions inside PL/SQL packages.
    Technologies: Oracle9i

  • Database Team Leader

    1999 - 2002
    Strom Telecom, Doubravice, Czech Republic
    • Designed, developed, optimized, and administered massive telecom databases for clients in Russia, Czech Republic, and Germany.
    • Designed the database model of wholesales billing and least cost routing for Callax and Dusseldorf, Germany.
    • Migrated the telecom billing system from SQL Server to Oracle.
    • Implemented central ODS of telecom billing for MGTS, Moscow.
    Technologies: Visual Basic 6 (VB6), Sybase, Oracle9i, SQL Server 2000

Experience

  • Financial Market Data for Traders

    Spikeet provides access to 20+ years of historical financial data, with advanced filtering platform. I was responsible for redesigning MySQL query patterns used for built-in data tracking tools. I was able to reduce query execution time 12-80 times for various query patterns.

  • Portal for Job Seekers
    https://www.monster.com/

    Job Seekers portal pages received on average 8,000 hits per second at the time I was working for Monster as a database engineer. I participated in defining and enforcing SQL Server standards and best practices. My tasks included code review, design review, and performance optimization. I was responsible for T-SQL stored procedures code review produced by more than 40 developers located in Prague, Czech Republic, and Maynard, Massachusets, USA.

  • FORIS - OSS/BSS System for MTS, Moscow

    FORIS is an OSS/BSS system consisting of billing, rating, provisioning, and resource inventory modules using massive Oracle databases with hundreds of millions of CDR rows loaded each hour. As a database team leader, I was responsible for designing the data model, PL/SQL development, database administration, and performance optimization. The system was successfully deployed, handling trillions of CDR data, inventory of hundreds of millions of cell phones, and other mobile devices and generates monthly invoices for 100 million subscribers.

  • PERSON Redesign for TV Nova, Czech Republic
    https://tv.nova.cz/

    PERSON is a user management system used by TV Nova web and Voyo streaming users. I was responsible for PL/pgSQL development, testing, reporting, and query performance optimization, including PostgreSQL indexes redesign.

  • Solving Bottlenecks With SQL Indexes and Partitions (Publication)
    https://www.toptal.com/database/sql-indexes-explained-pt-3
    Indexes and partitioning can help with SQL performance, but they're not cure-alls. Through everyday examples of date range and LIKE queries, find out how to "think like an RDBMS" to make yours run faster.
  • SQL Indexes Explained, Pt. 2 (Publication)
    https://www.toptal.com/database/sql-indexes-explained-pt-2
    Sorting a table can make some queries faster—but the maintenance cost is untenable. Enter real database indexes and their most common implementation structure: the B-tree.
  • SQL Indexes Explained, Pt. 1 (Publication)
    https://www.toptal.com/database/sql-indexes-explained-pt-1
    Properly used, an SQL database index can be so effective that it might seem like magic. But the following series of exercises will show that underneath, the logic of most SQL indexes---and wielding them correctly---is quite straightforward.

Skills

  • Languages

    Transact-SQL, PL/pgSQL, Visual Basic 6 (VB6), Python 3

  • Paradigms

    Database Development

  • Storage

    Database Modeling, Microsoft SQL Server, MySQL, PostgreSQL, Oracle PL/SQL, PL/SQL, Oracle 10g, Oracle9i, SQL Server 2000, Sybase

  • Other

    Database Optimization, Performance Tuning, Indexing, TIBCO, BizTalk, Microsoft Project Server, Embarcadero RAD Studio

  • Platforms

    Oracle, TestComplete

  • Frameworks

    .NET

  • Tools

    Microsoft Dynamics CRM, LoadRunner, TFS, Subversion (SVN), Rational ClearQuest

Education

  • Master's Degree in Computer Science on the Faculty of Mathematics
    1982 - 1989
    University of Belgrade - Belgrade, Serbia

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