Dusan Nosal
Verified Expert in Engineering
BI Analyst and Developer
Bratislava, Bratislava Region, Slovakia
Toptal member since October 31, 2022
Dusan is a BI analyst and developer with experience across multiple business areas—banking, real estate, insurance, municipality, newspapers, and cinemas. He is passionate about the entire process of designing BI solutions, from analyzing source data through the design and creation of data warehouses, ETL processes, and data marts to the final visualization. Dusan's background is primarily with Microsoft and Oracle BI tools.
Portfolio
Experience
- Data Analysis - 10 years
- Data Transformation - 8 years
- Microsoft SQL Server - 8 years
- T-SQL (Transact-SQL) - 8 years
- SQL Server Integration Services (SSIS) - 5 years
- Microsoft Power BI - 5 years
- SQL Server Reporting Services (SSRS) - 3 years
- SQL Server Analysis Services (SSAS) - 3 years
Availability
Preferred Environment
Microsoft Power BI, Microsoft SQL Server, SQL Server Integration Services (SSIS), SQL Server Reporting Services (SSRS), SQL Server Analysis Services (SSAS), Oracle Database, SQL Server Management Studio (SSMS), SSRS Reports
The most amazing...
...achievement is an end-to-end build of a financial data mart for a client in the banking sector.
Work Experience
SSRS Reports Developer
Syngenta - Digital Product Engineering
- Developed eight paginated reports using the Power BI Report Builder tool. The development work included advanced groupings, aggregations, expressions, and maps displaying.
- Prepared datasets for paginated reports as queries over PostgreSQL database containing tables with data stored in JSONB format.
- Embedded paginated reports into Power BI Desktop reports with binding dataset parameters into report filters.
Consultant
Joseph Smith & Sons, Inc.
- Developed a master Excel reporting spreadsheet that combined various source data Excel files submitted daily by different facilities.
- Implemented the new reporting Excel spreadsheet. Saved approximately one hour per day since the reporting was daily and was done manually prior.
- Analyzed source data Excel files from different facilities with a completely different structure but bearing the same information to unify them in a single report.
Business Intelligence Analyst | Developer
Freelance Clients
- Analyzed the requirements to be covered by final reporting and available data sources.
- Designed logical and physical data model of a new financial data mart and developed the data mart on Microsoft SQL Server 2019. The data mart was to cover around 2000 attributes and 100 reports.
- Participated in an extension of existing financial data mart built on Oracle Database 19c. Analyzed the current solutions for reporting based on SAS language to acquire all the requirements.
- Examined new data sources and reconciled balances from the new data sources to the general ledger balances. Designed and developed all data flows from data sources to final reports.
Senior Business Intelligence Consultant
ICA Group
- Created a Power BI dashboard showing near real-time data (refreshing every 15 minutes) from more than 40 SQL servers.
- Migrated approximately 40 reports from SAP BusinessObjects to SQL Server Reporting Services, including changes in the original source data.
- Migrated a data warehouse (DWH) from one Microsoft SQL server to another, including the replication of all database objects—tables, views, Integration Services (SSIS) catalog, environments, jobs, etc.
- Built and maintained over 100 ETL processes in SQL Server Integration Services to feed a DWH using dynamic connections to 40 Microsoft SQL Servers.
- Analyzed data sources and processes in AWS and prepared functional analysis, which resulted in designing a new DWH.
Senior Business Intelligence Consultant
Sogeti
- Analyzed a municipality client's requirements for a dashboard and its alignment with available source data.
- Developed a DWH based on Microsoft SQL Server 2012, ETL process in SQL Server Integration Services, and data mart using SQL Server Analysis Services.
- Devised a dashboard in the Power BI desktop tool using SQL Server Analysis Services cube as source data.
Senior Procurement Analyst
Johnson Controls
- Migrated reports from Microsoft Access to Microsoft SQL Server, resulting in a 50% saving on time spent on reports preparation.
- Extracted and consolidated data from multiple ERP systems such as Oracle, SAP, and iScala monthly.
- Analyzed data and created global regular and ad hoc supply chain management reports using Microsoft Excel, Access, Power BI, and SQL Server.
Asset Management Data Analyst
Hewlett Packard Enterprise
- Processed manual database updates according to requests received through email or the Remedy ticketing tool.
- Requested mass updates, database cleanups, and adjustments through IT tickets.
- Exported data from FactoryTalk Asset Centre and Remedy tools; created reports in Microsoft Excel.
Experience
Near Real-time Data Dashboard
The project entailed the preparation of a data mart based on Microsoft SQL Server 2016, an ETL process using SQL server integration services, bringing data from 40 Microsoft SQL servers and a Power BI desktop in direct query mode.
Financial Data Mart
The data mart consisted of 70 tables and a complex ETL process based on 100 stored procedures and was about to cover around 20 financial reports.
The development of this solution passed through the following phases:
-Functional analysis of requirements to be covered by financial reports
-Analysis of data sources, design of logical and physical data model
-Development of the new data mart on MS SQL Server
Power BI Dashboards
The data warehouse was modeled and developed on MS SQL server. Over the data warehouse, a small data mart in SQL server analysis services has been deployed and used as a source for Power BI dashboards.
Education
Master's Degree in Finance, Banking, and Investments
University of Economics in Bratislava - Bratislava, Slovakia
Skills
Tools
Microsoft Power BI, Excel 2010, Microsoft Access, Microsoft Excel, Git, Power Query, BMC Remedy, Microsoft Report Builder
Languages
SQL, T-SQL (Transact-SQL), Excel VBA
Paradigms
ETL, Functional Analysis, Business Intelligence (BI)
Storage
Microsoft SQL Server, SQL Server Management Studio (SSMS), Data Integration, SQL Server Integration Services (SSIS), SQL Server Reporting Services (SSRS), SQL Server Analysis Services (SSAS), SQL Stored Procedures, Databases, Relational Databases, Data Pipelines, Database Architecture, RDBMS, Oracle SQL Developer, SQL Server DBA, PostgreSQL
Platforms
Oracle Database, Azure, Microsoft Dynamics 365, SharePoint
Other
Dashboards, Data Visualization, Data Transformation, Data Cleansing, Data Reporting, Reports, Excel 365, BI Reporting, Dashboard Design, Data Structures, Reporting, Data Analytics, Finance, Economics, Analytics, Relational Database Design, Data Engineering, Data Analysis, Financial Data, Data Modeling, DAX, Data Warehousing, ETL Tools, Data Architecture, SSRS Reports, Warehouses, Commercial Banking, Investments, Asset Center, Pagination
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