Peter Hajnal

Peter completed his degree in Economics with a specialization in Tourism. After a longer period of traveling, he found his interest in computer sciences. Before deciding to have a career in data analysis he was learning Java Script and Data Science online. During his placements, he came across a variety of projects including the following: Completed performance checks and optimized dashboards in Tableau after cloud migration ensuring a smooth shift from server to cloud enabling a better client experience. Constructed a comprehensive framework for dashboard development and defined a QA checklist for the BI Team to elevate precision while reducing errors. Standardizing the process reduced the development time by 30-40% and created transparency for management to oversee projects and check quality. Built a series of Power BI dashboards to evaluate survey data. This helped the client decide on changes to their subjects and course offerings increasing their efficiency. Resolved any data and performance issues related to workbooks and data sources. Designed, developed, and validated Alteryx workflows for automating reports, resulting in an accelerated reporting process saving significant time. Provided technical support and Alteryx training to elevate the team's overall competency and become more efficient saving approximately £25,000. I was also a project manager where a team had to find insights into a police-related dataset that could be used in a mayoral campaign. Carried out a thorough Alteryx research on DCM and SDLC and best practices to support standard operating procedures.

Certifications

Blog Posts

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Fri 02 Aug 2024 | Peter Hajnal
Optimizing Performance in Power BI with DAX
In Power BI Desktop, you can find out how each of your report elements, such as visuals and DAX formulas, are performing
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Thu 27 Oct 2022 | Peter Hajnal
Dashboard week day 3 - fine tuning the process
With useful feedback from yesterday's presentation, I started this one with more ideas of how my day will look like. Think-Plan-Execute-Think-Eat-Think-Execute
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Wed 23 Nov 2022 | Peter Hajnal
Setting up and connecting to an IBM DB2 server in Tableau
Step 0. Gather all the credentials you need: ·    Server: ·    Port :         ·    Database:         ·    User ID: ·    Password: Step 1. You can only connect to IBM DB2 server directly  if the database is z/Os and not iSeries. Tableau doesn’t support iSeries
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Wed 26 Oct 2022 | Peter Hajnal
How to work quick
Make a plan. Told it before, will tell again. To myself too, for sure. But what if the plan goes out the window? Do not panic. Take a deep breath and ask question
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Tue 25 Oct 2022 | Peter Hajnal
How to PM
At some point in your Client Project you will be asked to be the Project Manager. While I'm pretty sure you heard the term before, in case it's not quite clear for you what is about when it comes to The Data School, here's a little intro. Before the initial client call, check your emails
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Tue 25 Oct 2022 | Peter Hajnal
Tableau Certified Data Analyst Exam
You find a lot of useful information on convo about the exam here Certified Data Analyst Exam - Convo I also wanted to add my opinion on it and how I found it.  First of all, get ready to be annoyed a little bit. Registering and setting up your exam date is fairly easy
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Tue 25 Oct 2022 | Peter Hajnal
Dashboard week: day 1
Day one is over for our dashboard week. We've been tasked to make accessible dashboards for people with disabilities. We had the choice to decide what kind of disability are we focusing on. After going through the options, I decided to make a universal dashboard. Next step was to make a plan
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Wed 21 Sep 2022 | Peter Hajnal
Stats 101 : Z-Score
A Z-score is a numerical measurement that describes a value's relationship to the mean of a group of values. Z-score is measured in terms of standard deviations from the mean
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Thu 25 Aug 2022 | Peter Hajnal
Formatting Axes
Photo by Gabriele Tirelli / Unsplash How to format your axes in Tableau
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Mon 22 Aug 2022 | Peter Hajnal
Format Borders and Lines
by Peter Hajnal As the title says, this blogpost is all about basic formatting tips. These are found in the format borders and format lines pane in Tableau
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Wed 10 Aug 2022 | Peter Hajnal
Containers/Excalidraw
Week 6 and we are learning about dashboards. One good idea is to always draw your ideas, drawing is great. Helps you clarify what and how do you want to show data on your dash. It also makes dashboarding a whole lot quicker
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Wed 27 Jul 2022 | Peter Hajnal
Extracts in Tableau server
An extract in Tableau is a representation of your data that you have saved from your data source. This can speed up dashboards, but also allow certain advantages, such as using Tableau functionality that isn't available in the original data, or supporting very large data sets
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Mon 25 Jul 2022 | Peter Hajnal
Tableau dates exercise (1st remote day)
Welcome back everyone, as I said in my previous blogpost we will continue with ̶a̶l̶t̶e̶r̶y̶x̶ ̶M̶a̶c̶r̶o̶s̶  Tableau. After a quick catch up from week 2 we dived into Table Calculations with date and time with Lorna
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Thu 21 Jul 2022 | Peter Hajnal
Confused yet?
Slowly getting to the end of Week 3, a day before the Alteryx Core Exam.  Last few days we practiced what we already learnt, and got a handful of good ideas, know-hows, and best practices from Angelos. We were started to gain a bit of confidence, but was time to learn something new
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Thu 14 Jul 2022 | Peter Hajnal
Reference band vs Reference Line
Reference line: It’s a  line that gets drawn on a chart that represents another measure or point of reference. Reference lines can be useful in providing context to the related chart
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Tue 12 Jul 2022 | Peter Hajnal
Filtering Blue vs Filtering Green
Filtering is super useful in Tableau. We can organize and simplify our data with it and we like that. There are 6 different type of filter options: 1. Extract Filter 2. Data Source Filter 3. Context Filter 4. Dimension Filter 5. Measure Filter 6
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Thu 07 Jul 2022 | Peter Hajnal
Is transparency the new standard?
Beside understanding the basics of Alteryx and Tableau Prep, as a newbie, my first week was all about settling in, and getting familiar with the company’s culture. Many new faces, few familiar ones from interviews and Meet & Greets
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