Jaroslav Tomcala

Jaroslav has over 15 years of experience in various business positions, including sales representative, account manager, supervisor, marketing specialist, web designer, and compliance coordinator. Throughout his career, he has consistently prioritised clients' needs and strived to deliver exceptional service with a strong focus on details.

In some of these roles, he used data to improve his sales performance, time management, or measure the success of marketing campaigns. His real passion for data started back in 2020 when he took a data analytics course, gaining a deeper understanding of various analytical tools and techniques, and data cleansing.

With a good understanding of Tableau and Alteryx (Designer Core Certified), he is eager to leverage these tools to assist others in comprehending their data. Moreover, he is contributing to the thriving data community.

In his spare time, he travels, photographs, and goes to galleries, museums, theatres, and concerts.

Certifications

Blog Posts

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Sun 03 Dec 2023 | Jaroslav Tomcala
Dashboard Week: Day 4 & 5 - DataPlusMovies
I was excited when we received Jenny's brief on Thursday at 9 am—a rarity in our Dashboard Week as the challenge extended to Friday too! The task at hand was the Data + Movies challenge for our final two days
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Wed 29 Nov 2023 | Jaroslav Tomcala
Dashboard Week: Day 3 - Spatial Analysis and Reporting in Alteryx
Today, we had to connect to the Aviation API and perform spatial analysis. The entire task had to be completed using only Alteryx. Subsequently, the workflow must be uploaded to the Alteryx Server, where users can view/download the resulting report
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Sun 05 Nov 2023 | Jaroslav Tomcala
Did you know that in Tableau, you can...
...easily switch between sheets on your dashboard with just one click, without losing any of the layout settings? Let me show you how.
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Sun 05 Nov 2023 | Jaroslav Tomcala
Did you know that in Tableau, you can...
...have multiple colour palettes for your measures? Have you ever wondered how to use different colors for various measures in Tableau? My tutorial's got you covered! Learn the ropes of creating multiple color legends effortlessly.
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Sun 15 Oct 2023 | Jaroslav Tomcala
GA4 by Tableau – Connect Tableau and Google Analytics
Google Analytics Connector for Tableau is a tool that allows users to integrate their Tableau visualizations with data from Google Analytics. It's beneficial because it enables in-depth analysis of user behavior on websites through interactive charts and dashboards
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Thu 31 Aug 2023 | Jaroslav Tomcala
DAX Cheat Sheet - Essentials
In this blog about essential DAX (Data Analysis eXpressions) expressions in Power BI, I'll guide you through the fundamental functions you need to know. Keep in mind that the parameters enclosed in square brackets [ ] are [optional], and that ellipsis ..
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Thu 31 Aug 2023 | Jaroslav Tomcala
My First MakeoverMonday in Power BI
Our first MakeoverMonday (2023, week 19) in Power BI was about MakeoverMonday metadata. It was a fantastic dataset, although it needed a bit of tweaking in Power Query. My first task - determine the exact date using only the column with the year and week number
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Wed 30 Aug 2023 | Jaroslav Tomcala
Empower Your Visuals in Power BI: Using Parameters to Change Dimensions and Measures
We're currently in the middle of our week, concentrating on Power BI and Power Query at The Data School. Today, I'd like to introduce you to a useful feature we've picked up
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Tue 22 Aug 2023 | Jaroslav Tomcala
Mobile Layout View in Power BI
Today was our first day with Power BI, and we learned a lot about Power Query and building Power BI pages (dashboards)
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Sun 20 Aug 2023 | Jaroslav Tomcala
Connected Scatter Plots - How to Show Time Series
After I wrote my blog post about Scatter Plots, I thought it would be great to take one more step further and write about how to visualize changes over time using them
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Sun 20 Aug 2023 | Jaroslav Tomcala
Let's Talk About Scatter Plots - Introduction
What is a Scatter Plot? A Scatter Plot (also known as a Scatter Graph or Scatter Chart) is a visual representation of data points on a graph, where each data point is represented as a dot (a mark in Tableau)
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Wed 09 Aug 2023 | Jaroslav Tomcala
What Can Help You Get to The Data School?
It's a question that undoubtedly crosses the minds of those aspiring to work at The Data School. Allow me to offer some insights that could light your path on this exciting journey.
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