Messy Data Is Part of the Job. Knowing How to Fix It Is the Skill.
Real-world data arrives duplicated, inconsistent, incomplete and badly structured. Learn how to clean it, combine it, reshape it and build repeatable preparation flows before the analysis even begins.
Before You Can Analyse the Data. You Have to Make It Usable.
The dashboard is often the last step. First, analysts have to take information scattered across different files, systems and structures and turn it into one reliable source for analysis.
Great analysis starts with data you can actually trust.
Real Data Is Rarely Ready. Tableau Prep Gets It There.
Clean, combine and shape messy data from multiple sources into a reliable flow that is ready for the analysis you actually want to perform.
See Every Change You Make. Understand the Journey Your Data Takes.
Tableau Prep gives you a visual workflow for data preparation. See how each cleaning step changes the data, trace issues back through the process and understand exactly how your final output was created.
Track Every Step. Understand What Changed.
Visualise every cleaning step, track your actions and learn how unions, joins, calculations and transformations change your data as it moves through the flow.
Cleaning Data Is More Than Removing Nulls.
Real data contains inconsistent formats, incorrect data types, duplicate values, badly structured text and unexpected gaps. Learn how to identify these problems and fix them systematically.
Sometimes One Dataset Isn't Enough.
Real analysis often starts with information scattered across different systems and files. Tableau Prep brings those sources together, models how they relate and turns them into one dependable dataset ready for analysis.
Multiple Sources.
One Business Question.
The information you need may live in completely different places.
Customers, regions and segments
Orders, revenue and purchase values
Targets, budgets and recurring exports
Make the Data
Work Together.
Define how those separate pieces should connect, combine and transform.
Match related records across different tables
Stack similar datasets into one larger table
Summarise, calculate and reshape the data
One Dataset.
Ready to Be Trusted.
The result is a stable foundation your analysis and dashboards can rely on.
Consistent and dependable every refresh
Structured around the questions you need to answer
Ready to run again as new data arrives
Multiple Sources. One Connected Flow.
Combine data from different systems and structures into one clean, connected preparation flow that can feed your analysis with confidence.
Sometimes the Data Structure Is Wrong. So Change the Structure.
Data is often designed for collection or reporting rather than analysis. Tableau Prep lets you change that structure into something easier to filter, visualise and maintain.
| January | February | March | April |
|---|---|---|---|
| 120 | 148 | 173 | 159 |
Wide Format
Each time period is stored as a separate column. This is common in spreadsheets and management reports.
- New months require new columns
- Harder to filter by month
- Harder to build flexible visualisations
- Structure changes as new data arrives
| Month | Sales |
|---|---|
| January | 120 |
| February | 148 |
| March | 173 |
| April | 159 |
Long Format
The month becomes a dimension and the sales figure remains a measure.
- Easy to filter by month
- Works naturally with Tableau
- New months become new rows
- Structure stays consistent as data grows
It can be useful for simple human-readable reports or when each column genuinely represents a different measure.
When repeated columns represent the same type of information, reshaping them into rows usually gives Tableau much more flexibility.
Reshape the Data. Not the Question.
Stop Cleaning the Same Data Over and Over Again.
Once a flow works, reuse it. Build repeatable preparation processes, publish flows to Tableau Cloud and turn recurring data work into a process that can run again when new data arrives.
Clean → Transform → Output
Ready for analysis
Schedule It.
Your preparation flow doesn't need you sitting there pressing a button every morning. Publish it to Tableau Cloud and schedule it to run automatically.
Build It Once. Run It Again.
From Manual Preparation to Repeatable Automation.
Deploy flows to Tableau Cloud and turn your preparation process into something that can run on schedule, refreshing the data model automatically when the next batch of data arrives.
Tableau Prep
148 Guided Lessons. The Complete Preparation Workflow.
Go from loading your first dataset to building complete, repeatable data preparation flows that clean, calculate, combine, reshape and output analysis-ready data.
