Data Cleansing can be Frustrating unless you have the Right Tools
Even without a paid license, you can still watch along to understand Why and How we Clean Data
Data often comes from different teams, formats, or even companies — combining it creates one clear and reliable dataset.
Mastering combining data from multiple sources ensures you can bring scattered information together into one unified dataset.
You’ll discover how to merge inputs from different teams, formats, and even companies so your analysis is complete and reliable.
Real-world data is messy — we clean it so dates, names, and categories are consistent and accurate.
Mastering fixing incorrect or inconsistent entries ensures your data is trustworthy and ready for deeper analysis.
You’ll discover how to standardize values, remove errors, and ensure consistency across fields.
Sometimes the dataset doesn’t have what we need — so we build new calculations and fields to unlock insights.
Mastering creating new fields for analysis allows you to extend the value of your data beyond what exists in the raw files.
You’ll discover how to calculate metrics, derive new dimensions, and prepare data for richer visualizations.
Master Tableau Prep to transform raw data into clean, structured outputs. Build automated workflows and apply joins, unions, aggregations, calculations
Clean And Structure Data – Transform Messy, Inconsistent Fields Into Reliable Datasets
Build Automated Workflows – Create Repeatable Processes With Joins, Unions, And Calculations
Publish and Deploy Flows for Scheduled Runs – Automate your flows to feed multiple Dashboards across the Organisation
Transform messy, unstructured files into clean, reliable datasets ready for powerful analysis.
Mastering data preparation techniques gives you the ability to turn messy, inconsistent files into structured datasets that analysts can trust.
You’ll discover how to cleanse, reshape, and aggregate information so it’s always ready for visualization.
Automate your data preparation so dashboards stay up to date across the entire organisation.
Mastering publishing and deploying flows allows you to automate the delivery of clean, reliable datasets across your company.
You’ll discover how to schedule runs and feed multiple dashboards without manual effort.
01_01_Introduction to Data Cleaning and Preparation - Demo
01_02_Downloading and Installing Tableau Prep (Links)
01_03_The Trouble with Manual Cleaning in Excel
01_04_Excel vs Tableau Prep
02_01_Loading an Excel File - Interface Explained (Attach File)
02_02_Loading CSV Files - Interface and Delimitters (Attach)
02_03_CSV with Text Qualifiers
02_04_Data Interpreter (Attach)
02_05_Updating Connections (Attach)
02_05a_Special Note - Re-establishing Connections for Assignments
02_06_Building Our First Flow using Clean Step (attach)
02_07_Tableau Ecosystem (Attach)
03_01_Beginner Data Set Explained
03_02_Reading the Clean Step Interface - Sorting, Reordering, Change Log
03_03_Renaming Fields, Organising Steps, Renaming Steps and Providing Descriptions, Build Life Cycle
03_04_Keep and Exclude Fields, Rearranging your Flow, More on the Change Log
03_05_Branching Basics, Upper, Lower and Title Case, Trimming, Removing Extra Spaces and Removing al
03_06_Splitting Fields - Automatic vs Custom
03_07_Cleaning Text - Remove Letters, Numbers and Punctuation _ Duplicate Field
03_08_Filtering Row Entries
03_09_Renaming Individual Rows, Manual Grouping, Ungrouping, Creating New Fields with Duplicate and
03_10_Identifying Duplicate Rows - Important Factors to Consider
03_11_Filtering Dates - Selected Values, Range of Dates, Relative Dates
03_12_Converting Dates - DatePart Calculation - Preview in Tableau Desktop
03_12a_Filtering Numbers and Strings - Selected, Range, Wildcard
03_13_Assignment Explained
03_14_Assignment Walkthrough
03_15_Getting Started with Calculated Fields - Basic Arithmetic
03_15a_Rounding, Integer, Absolute, Sign
03_16_Len, Find, Contains, Findnth
03_17_Left, Right, Mid
03_18_Replace, Startswith, Endswith
03_19_Date Functions - Day, Month, Year, Today and Now
03_20_MakeDate, MakeTime, MakeDateTime - Nested Functions Theory
04_01_The Basic Concept of Aggregate Functions with an Excel Demo
04_09_Assignment 2 - Walkthrough
04_10_Assignment Walkthrough Solution
04_02_Basic Aggregation Types in Tableau Prep - Creating multiple Branches - SUM, MAX, MIN, COUNT, D
04_03_Grouping by More than One Field
04_04_Aggregating Over Dates - Using Convert Dates Feature - Day(), Month(), Year()
04_05_Comparing Two Aggregates - Building Full Flows - Multiple Aggregate Steps
04_06_Applying Aggregates in Interesting Ways - Aggregates of the Aggregate
04_07_Assignment Walkthrough (Attach Questions)
04_08_Assignment Solution (Redo)
05_08_Assignment (Attach Questions)
05_01_Pivot and Table Structure Explained - Advantages and Disadvantages
05_02_More Examples of Advantages and Disadvantages of Pivot vs Table
05_03_Table to Pivot, Pivot to Table
05_04_WARNING. Unpivoting can cause Numerical Duplicates and Errors
05_05_Pivoting off Calculated Fields - Learning Iteration Design
05_06_Date Truncation followed by Pivot Analysis
05_07_Multi-Level Pivot - HACK Methodology
05_08_Assignment (Attach Questions)
05_09_Assignment Walkthrough (Attach Prep File) - Part 1
05_10_Assignment Walkthrough (Attach Prep File) - Part 2
05_11_Assignment Walkthrough (Attach Prep File) - Part 3
“
AMAZING TEACHER
I love your course and could listen for hours. You distill valuable advice clearly. Found you on YouTube while struggling with LOD expressions; examples helped immensely. Grateful for accessible pricing and free content—your teaching is engaging and generous.
Emeline Courcelle
“
GAME-CHANGING COURSE FOR FIRST-TIME TABLEAU USERS
This course is a must for first-time Tableau users intimidated by data. Jed simplifies Tableau with step-by-step guidance: setup, import data, navigate the UI, and create visualizations. Clear, encouraging teaching—confidence transformed and ready to build. Thanks for making Tableau accessible.
Adam Lockwood
“EXCELLENT COURSE
Jellyman is an excellent teacher! His content is interesting, applicable and well-explained.
He has clearly thought about the way people absorb information and doesn't gloss over any assumed knowledge like many other courses do. He has taken the time to go through methods & concepts step by step so it's almost impossible not to learn!
”
Elizabeth Deterding
“AMAZING COURSE
The course is great! Feels like studying with a friend :) Everything is explained very easily and I am looking forward to the next one!
”
Anastasiia Larina
“BEST TABLEAU TRAINING EVER
Totally clear and very well explained with a bunch of examples. All sensible topics – LOD, Actions and Calculated Fields are tackled.
Big Thank You!
”
Nicolaie Cozma
“I LOVE LEARNING TABLEAU WITH JED
The best teacher of Tableau I have ever found! I would love to meet Jed someday in real life. I like his sense of humor and the way he explains everything.
Jed much thanx for this course.
”
Emilia B Korycka
“JOINS WERE HOLDING ME BACK
Great – this was holding me back but not any more
”
Brian Sundermeijer
“STILL LEARNING THINGS
I was wondering why we were just now covering joins when it's something I felt essential enough to be a beginner subject. Then you delved into joins versus relationships versus blends and it became much clearer – this was more complex than an entry level subject.
Great explanations all around and I have a better understanding of when to use which tool.
Update: Just finished LODs. Mind continues to be blown! Can't recommend this course enough.
”
Bryan Nylander
“ONE OF THE BEST EDUCATORS ON PLANET TABLEAU
Jellyman is a fantastic teacher! His lessons are unlike others to say the least!!!
Hats off to his engineering personality and his koool sense of humour (A bit of contradiction there but definitely works like magic on our memory capacity to retain his fun lessons :)
”
“AMAZING!
Take this course even if you think you're an expert in Tableau
”
Kamirah Martin
Tableau Prep is not free. It’s included with the Tableau Creator License (paid subscription), which also provides Tableau Desktop and one Creator seat on Tableau Cloud/Server.
Tableau Prep is a tool for data preparation—cleaning, shaping, and combining datasets—while Tableau Desktop focuses on visualization and analysis. Together, they provide a complete end-to-end data workflow.
No. Tableau Prep can be used on its own. However, it is most effective when paired with Tableau Desktop or Tableau Cloud/Server, where you can publish your cleaned data for dashboards and reporting.
Yes. Flows created in Tableau Prep Builder can be published to Tableau Cloud or Tableau Server. Once published, you can schedule automatic refreshes so your datasets stay up to date without manual effort.
Tableau Prep uses sampling by default to improve performance while designing flows. You can configure it to use the full dataset, but for very large sources it’s best to process them through Tableau Cloud/Server.
Yes. Flows can be exported as .tfl or .tflx files and shared directly, or published to Tableau Cloud/Server for teammates to run, reuse, and schedule. This makes collaboration much easier.
No coding is required—Tableau Prep uses a visual drag-and-drop interface that anyone can learn. Some knowledge of SQL and data concepts can make flows more efficient, but it isn’t necessary.
This is where your journey begins here at Jellyman Education. You'll get a quick feel for what Tableau is and why it's such an amazing tool.
Now that you've made it through the "Getting Started with Tableau" course, it's time to get stuck into the real training! Here you'll learn a strong foundation of tools used throughout Tableau that prepares you perfectly for the future.
Now it's getting really good! Intermediate covers everything from Data Cleansing, Project Management, Data Structure, Quick Table Calc's, Advanced Filtering and Advanced Maps. You'll be the star of the show with these skills!
You're now delving into some of the highest and most complex operations you'll find in Tableau. LOD's, Joins, Unions, Big Data, Blending, Parameters, Sets, Advanced Dashboards and Custom Visualizations. WOW INDEED!!!!
Now it's getting really fun. Think of Tableau Cloud as the digital cafe where you and your friends meet up to share stories, information, dashboards, data, results and more. It's the future of Data Sharing in the Industry today.
With Visualizations through Tableau Desktop and data sharing through Tableau Online, it's time to tackle Advanced Data Cleansing using Tableau Prep. This is one of the most enjoyable tools you'll find especially if you clean data all day long!
Master the essentials of data analysis with SQL, ChatGPT, AI-powered SQL, and project management. Gain practical skills to solve real problems and boost your career as a data analyst.
Perfect for job seekers and freelancers—these Tableau projects help you build a standout portfolio on Tableau Public. Showcase your data skills, design thinking, and storytelling in real-world scenarios that make sharing and impressing easy.
Learn how to land your dream data analyst job with a proven system: avoid common mistakes, craft powerful applications, ace interviews and testing, and turn rejection into growth. Build confidence, skills, and a portfolio that gets you hired.
It Contains 3 Main Sections: SQL, AI and Project Management
