John Power

After graduating from the University of Southampton with a degree in Music, John worked in several different industries before settling on financial services.

In the latter half of his four years in financial services John worked in Data Operations, and it was in this role that he discovered Power BI, and then inevitably, Tableau. Given the presence of The Information Lab within the online Data community, it was only a matter of time before John stumbled upon The Data School and was drawn in by the unique training opportunities that it offered.

John has been able to apply this training across a number of various industries; automotive, security and aerospace, financial services and sports analytics to name a few.

Despite the detour after graduating, John still enjoys playing and listening to music in his spare time, as well as gyming, surfing and climbing.

Blog Posts

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Fri 28 Jul 2023 | John Power
Dynamic Title for Singular / Plural
In Tableau it is always good practice to include a title so viewers and users are clear on what a visualization is representing. Below we have a treemap showing the Sales by sub-category for different regions
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Fri 28 Jul 2023 | John Power
Tableau Date Functions: Testing for Future Dates
Date functions are some of the most useful and frequently used in Tableau. However, there are times when we want to see the outcome of a date (usually in the future) that is not within our data set. In this example I am using a data set that runs up to 30/12/2022
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Fri 28 Jul 2023 | John Power
Continuous Line Chart: Removing that unwanted line
In the pictured line chart, I needed the Date field to be continuous so that I could add a Set Action for the user to select a range of Dates - (see step by step guide on this: https://www.youtube.com/watch?v=ScZrHKq-vIs)
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Mon 24 Jul 2023 | John Power
(part 3 of 3) Creating, Formatting and Displaying our % Change
This guide follows on from https://www.thedataschool.co.uk/john-power/creating-a-comparison-range-based-off-of-chosen-month-range/ in which we calculate our 'Sales for Comparison Month Range'
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Sat 04 Mar 2023 | John Power
(part 2 of 3) Creating a Comparison Range based off of a Chosen Month Range
This blog follows on from https://www.thedataschool.co.uk/john-power/creating-a-start-and-end-date-month-selectors in which Start Date and End Date parameters were created and used to view the SUM of Sales for a selected month range
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Wed 01 Feb 2023 | John Power
(part 1 of 3) Using a Start Date and End Date Parameters to change Months in view
For this example I will be using the US Superstore Date Set to display the SUM of Sales by Month of Order Date. This guide will break the process down into 4 sections: 1. Creating our DATETRUNC 2. Creating the Start Date and End Date Parameters 3. Creating our Boolean Calculated Field 4
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Thu 12 Jan 2023 | John Power
How to run a Performance Test on a Dashboard on Server
First of all you need to ensure that the Dashboard is embedded on your server. Then you need to navigate to view the required Dashboard on the server: The below needs to be added to the end of the URL: ?:record_performance=yes So this: https://tableauserver.theinformationlab.co
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Thu 12 Jan 2023 | John Power
Alteryx: Directory Tool & Dynamic Input
The Directory Tool returns a list of files contained in a specified directory along with relevant file attributes. The Dynamic Input reads and processes from any input files or databases
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Wed 11 Jan 2023 | John Power
Alteryx: Publish to Tableau Server Tool
Once a workflow is created in Alteryx is it very common for Tableau Desktop to then be utilized for any required data analysis and visualizations. After the Publish to Tableau Server Tool has been dragged onto view and connected to the workflow, to the left a new pane will pop up
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Tue 10 Jan 2023 | John Power
How to view full in Tableau Web Edit
In Tableau Desktop it is relatively straightforward to view full data, all that you need to do is right click on the data source and select 'View Data': However, currently in Web Edit we are unable to do this
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Thu 15 Sep 2022 | John Power
How to remove the yellow highlight on a Chart when using a Dashboard filter
So to actually example what the title means: Before hitting this hurdle I used this blog https://www.thedataschool.co.uk/sophie-higson/what-is-the-difference-between-count-and-count-distinct to get rid of the 'greying out' when clicking on a graph
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Thu 01 Sep 2022 | John Power
How to color table columns distinctly
For this example we will be using the Superstore dataset. Here we have a simple table showing the '# of Orders', 'Discount', 'Profit', and 'Sales' for each month of 2018: We want the columns of '# of Orders' and 'Discount' to be colored grey, but 'Profit', and 'Sales' to be colored blue
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Tue 30 Aug 2022 | John Power
Dynamically displaying a measure value in your Tooltip
So to explain what I mean by this - if you have created a chart that uses a parameter to switch between the measure being displayed, it is important to include a Tooltip that will also update accordingly based on the Parameter. First we need to build out an example chart to use this on
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Thu 30 Jun 2022 | John Power
Dashboard Week: KPI Dashboard for San Francisco Rent Prices
For today's task we were required to create an "exceptionally designed KPI dashboard" using a data set on San Francisco rent prices (https://www.katepennington.org/data). The first thing I wanted to do was decide who my user would be, and how the Dashboard would help them
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Wed 29 Jun 2022 | John Power
Dashboard Week: Accessibility Design Task
Using data from FixMyStreet.com, for today's task we were required to create a Dashboard that made the data visualization experience open to as many people as possible. A screenshot of my final Dashboard is shown at the bottom of this post
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Wed 15 Jun 2022 | John Power
How to Build a Cohort Analysis graph
Finished graph: For this example we will be using the Superstore dataset
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Wed 15 Jun 2022 | John Power
How to use the Multi-Row Formula tool
For This explanation we will be using the 2020: Week 32 Preppin' Data Challenge (Cheers Carl) - https://preppindata.blogspot.com/2020/08/2020-week-32
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Sun 05 Jun 2022 | John Power
Shared Axis graph vs Duel Axis graph
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Tue 14 Jun 2022 | John Power
How to Check your Alteryx Server Version
Search https://spider.theinformationlab.co
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Wed 11 May 2022 | John Power
How to add custom colors in Tableau
First off, navigate to your Tableau Repository, right click on 'Preferences' and select 'Open with', 'Notepad': Something similar to the below will pop up: The quickest way to do this is copy and paste the existing color palette
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Sat 04 Jun 2022 | John Power
How to change your graph type using Measure Names
(A video version of this explanation can be found on Andy Kriebel's YouTube Channel - https://www.youtube.com/watch?v=nxCEfvu4D-w) Finished graph: In this example we will use the Sample - Superstore dataset
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Sat 04 Jun 2022 | John Power
How to create Top or Bottom N chart
Finished chart: In this example we will use the Sample - Superstore dataset
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Fri 22 Apr 2022 | John Power
Lessons from Client Project Week 1
Work as a team Within every Cohort that will be a range of skills and strengths, whether that be Tableau, Alteryx, presenting, communicating, design, whatever it is someone around you will be able to help in some way. So make the most of this, you are a team not an island
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Tue 10 May 2022 | John Power
How to create a Control Chart
Finished graph: For this example we will be using the 'London Airbnb Listings' dataset, and we want to create a control chart showing average price over time, separated by room
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Wed 27 Apr 2022 | John Power
How to quickly copy a color in Tableau
In this example we will use the Sample - Superstore dataset. First, create a line graph by dragging MONTH(Sales Order) onto Columns and SUM(Sales) onto Rows: Navigate to the worksheet that you wish to copy the existing color from
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Wed 27 Apr 2022 | John Power
How to create a single / double drill down bar graph
Finished single drill down graph: In this example we will use the Sample - Superstore dataset
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Tue 26 Apr 2022 | John Power
How to use a Parameter to select a range of dates on a line graph
Finished Graph: In this example we will use the Sample - Superstore dataset
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Tue 26 Apr 2022 | John Power
How to create a quadrant changing color scatter graph
Finished graph: In this example we will use the Sample - Superstore dataset
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Tue 26 Apr 2022 | John Power
How to create a highlight parameter action bar chart
Finished chart: In this example we will use the Sample - Superstore dataset
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Wed 13 Apr 2022 | John Power
Alteryx Joins with Alan, Annie and Andy (but not Barney)
The Join tool in Alteryx is used to combine two data streams, and with the help of Alan, Annie and Andy can we see just how this is done. This is Alan: Alan likes cooking, football and country walks. Alan has a friend called Annie, this is Annie: Annie likes yoga, reading and country walks
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Tue 29 Mar 2022 | John Power
How to create a Dynamic reference line
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Tue 22 Mar 2022 | John Power
Calculated fields: aggregate level vs row level
Calculated fields allow us to create new data from the data that pre-existed in our data source. They can be aggregate level, or row level, but never both together in the same calculated field
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Thu 17 Mar 2022 | John Power
Table calculations – LOCK IT IN
In the below screenshot we can see a simple table showing the sales of chairs, blinders, fasteners, accessories and machines broken down by segment: Once sales was dragged and dropped onto the text, Tableau defaulted the calculation to be the SUM
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Mon 07 Mar 2022 | John Power
3 simple but useful Alteryx features
Input / Output View With every tool used in Alteryx our data is changing in some way
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