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Showing posts from January, 2021

2021: Week 4

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This is the last in the 'Starter Challenges' series to get you up and Preppin' to start the new year. We've enjoyed running this mini-series so much we're already looking at creating another similar series later in the year.  This week's challenge involves picking up some more of the fundamental skills and gives you some chances to practice some of the skills you've picked up over the last few weeks. As always, we'll be guiding you along the way with some useful help links if you need a couple of reminders or chance to explore those new techniques.  The new technique for you to learn this week is Joins. If you've worked with different data solutions for a number of years, you'll be familiar with Joins but if you are new you're in for a treat! Joins allow us to bring two data sources together. This allows for much easier, richer and deeper analysis as data is often in many different locations. Use the help links if this is a new technique for

2021: Week 3 - Solution

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  Solution by Tom Prowse and you can download our full workflow here .  Week 3 was the third instalment of our Tableau Prep fundamentals challenges to kick off 2021. This week we were looking at the sales of bike accessories in our stores with a focus on pivoting and aggregation.  Step 1 - Wildcard Union Input Our first task this week is to input all of the sheets from the Excel document. You could bring all of these in individually and then use the union tool to combine them. However, there is an easier way of doing with functionality within the input step. By choosing 'Multiple Files' and then 'Wildcard Union' you can then make some selections about what files or sheets you want to be included. There is the ability to look at multiple files within a folder, but for our use case we want to include multiple sheets from the same file.  As we want to include all of the worksheets, we can leave the 'Matching Pattern' blank, however if, for example, we wanted to inc

2021: Week 3

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This week is the third in the Starter Challenges series we are running to kick off 2021.   This challenge will introduce you to the two main types of reshaping data, pivoting and aggregation. We used aggregation last week so we are building on this technique this week. We will also let you work with Unions where we stack data sets that have similar structures on top of each other.  As with all of our January 2021 challenges, we will be sharing useful links to helpful videos and articles that will give you more technical support if you need it.  This week's challenge sees us looking at the Accessory Sales at our Bike Store. Input One Excel sheet with 5 tabs of data: London Leeds York Manchester Birmingham The structure of the data is the same in each worksheet.  Requirements Input the data source by pulling together all the tables ( help ) Pivot 'New' columns and 'Existing' columns ( help ) Split the former column headers to form: ( help ) Customer Type Product Ren

2021: Week 2 - Solution

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  Solution by Tom Prowse and you can download the workflow here .  It's week 2 of the 2021 Preppin' Data challenges and we are continuing on our fundamentals journey by focusing on Aggregating and Calculations.  Again we were looking at Bike sales data and wanted to create some quick summaries to answer questions related to brand and store performance.  Step 1 - Create Brand Field The first step this week is to clean the Model field so that we only have the letters for each brand.  The first step is to duplicate the Model field. We do this because we want both Model and Brand within our dataset so can't just clean the Model field without first duplicating it. This can be achieved by Right-Clicking and choosing Duplicate Field. Once duplicated, we can use the Clean functionality within Tableau Prep to remove letters and punctuation. The Clean functions can be found by pressing the three dots, then selecting Clean:  Now we have cleaned the Model field to create our Brand fiel

2021: Week 2

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Building on from Week 1's challenge, we are going to take your data prep skills on one step further. The next steps we are introducing this week are: Aggregation - changing the level of granularity of your data. The combination of the categorical fields often sets what each row represents so aggregating data changes this. In Tableau Prep this is different from how we aggregate in Tableau Desktop. Calculations - If the value or variable that you need to use isn't in your data set, you will often be able to create it from the other data fields you do have.  As per last week, we've attached some help links that will teach you the techniques if you need a few nudges. One of the main challenges with Data Preparation is to think about not just what you want to do but the order you need to do those steps in. The challenge this week will be a good example of that to avoid repeating steps. Here's a post that might help you with your planning .  Also, thank you to all those who p

2021: Week 1 - Solution

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Firstly, a big thank you for everyone who has got involved with the challenge this week. The response on social media has been amazing and we have loved seeing all of the different solutions, especially across various tools. For anyone who is new to Preppin' Data, the solutions come in following parts:  Downloadable Workflow - these are Tableau Prep packaged workflows that you can download and unpick our solutions. Written Solution - a step by step blog post on how to solve the challenge. This is linked to the workflow that you can download. Video Solution - a walkthrough guide on how to solve the challenge. The written and video solutions may differ slightly as we want to show potential different ways of solving the problem.  Let's get started with 2021: Week 1's solution! Solution The solution is by Tom Prowse and you can download the workflow here . As a recap this week's challenge has a focus on cleaning data so that it's ready to answer some questions from ou

2021: Week 1

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Hello World... Welcome to 2021 Preppin' Data.  Since Jonathan (@JonathanAllenby) and I chatted by a coffee machine in Feb 2019, we along with Jenny Martin (@JennyMartinDS14) and Tom Prowse (@TomProwse1)  have produced 99 challenges to date, completed by 305 different people, who have solved the challenges 2,424 times (that we know of!).  The overall aim of Preppin' Data is to give people a place to learn the power of being able to prepare your own data sets (rather than relying on others) and the capabilities of Tableau Prep. If you want to know more, check out our first post . For those of you who are new to Preppin' Data, here are some basics: We release a new challenge each Wednesday We post a written and video solution the following Tuesday We build our challenges in Tableau Prep but welcome solutions from any other tool too.  One change this year is Jonathan is taking a step back from the challenges but will come up with a tricky problem every now and then I am sure.