Applied steps and undo in Power BI - Step-by-Step Guide

Introduction

Applied steps track every change you make to your data in Power Query. Undo lets you reverse recent changes if you make a mistake or want to try a different approach.

When you want to clean or transform data step-by-step and see each change recorded.

When you accidentally remove a column and want to restore it quickly.

When you want to test different filters or transformations without losing your previous work.

When you want to understand the sequence of changes applied to your data.

When you want to remove or edit a specific transformation step without starting over.

Steps

Step 1: Open

- Power Query Editor

The query and its applied steps appear on the right side in the Applied Steps pane

Step 2: Click

- Any step in the Applied Steps pane

The data preview updates to show the data state at that step

Step 3: Click the X icon

- Next to any step in the Applied Steps pane

That step and all steps after it are removed, and the data preview updates accordingly

💡 Removing a step deletes all later steps, so be careful to remove only the intended step

Step 4: Press Ctrl + Z or click Undo

- Power Query Editor toolbar

The last change you made is reversed, and the data preview updates to the previous state

Step 5: Right-click

- Any step in the Applied Steps pane

A menu appears allowing you to rename or delete the step

Before vs After

Before

Applied Steps pane shows: Source, Changed Type, Removed Columns; data preview shows all columns

After

After deleting 'Removed Columns' step, Applied Steps pane shows: Source, Changed Type; data preview shows all original columns including those previously removed

Settings Reference

Applied Steps pane

📍 Right side of Power Query Editor window

Shows the sequence of transformations applied to the data

Default: Visible when Power Query Editor is open

Undo button

📍 Home tab in Power Query Editor toolbar

Reverses the most recent change made in Power Query

Default: Enabled

Common Mistakes

Deleting a step in the middle without realizing it removes all later steps

Power Query removes the selected step and all steps after it, which can cause loss of multiple transformations

Only delete the last step or be prepared to redo later steps after deleting a middle step

Trying to undo changes after closing Power Query Editor

Undo history is lost when the editor is closed, so you cannot reverse changes made in a previous session

Use Undo immediately after a change or save versions of your queries before big edits

Summary

Applied Steps show each change made to your data in order.

You can delete or edit steps to adjust your data transformations.

Undo reverses recent changes but only while Power Query Editor is open.

Practice

1. What is the main purpose of Applied Steps in Power BI's Query Editor?

easy

A. To write DAX formulas for calculations

B. To create visualizations automatically

C. To track and record every change made to the data during cleaning

D. To connect Power BI to external databases

Solution

1. Step 1: Understand Applied Steps function

   Applied Steps record each transformation or change you make to your data in Query Editor.

2. Step 2: Differentiate from other features

   Applied Steps do not create visuals, write formulas, or connect databases; they track data cleaning actions.

3. Final Answer:

   To track and record every change made to the data during cleaning -> Option C

4. Quick Check:

   Applied Steps = Track changes [OK]

Hint: Applied Steps = your data cleaning history [OK]

Common Mistakes:

• Confusing Applied Steps with visualization features
• Thinking Applied Steps write formulas
• Assuming Applied Steps connect to databases

2. Which of the following is the correct way to undo the last applied step in Power BI Query Editor?

easy

A. Click the 'X' next to the last step in the Applied Steps pane

B. Press Ctrl + Z anywhere in Power BI Desktop

C. Delete the entire query and start over

D. Right-click the data table and select 'Undo'

Solution

1. Step 1: Locate Applied Steps pane

   The Applied Steps pane shows each change; each step has an 'X' to remove it.

2. Step 2: Undo last step by removing it

   Clicking the 'X' next to the last step removes that change, effectively undoing it.

3. Final Answer:

   Click the 'X' next to the last step in the Applied Steps pane -> Option A

4. Quick Check:

   Undo last step = Click 'X' [OK]

Hint: Undo last step by clicking 'X' in Applied Steps [OK]

Common Mistakes:

• Using Ctrl + Z which doesn't undo Query Editor steps
• Deleting entire query unnecessarily
• Looking for undo option outside Applied Steps

3. Given these Applied Steps in Power BI Query Editor:
1. Source
2. Removed Columns
3. Filtered Rows

If you click the 'X' next to Removed Columns, what will happen?

medium

A. Both 'Removed Columns' and 'Filtered Rows' steps will be deleted

B. 'Removed Columns' step will be deleted, and 'Filtered Rows' will be recalculated without it

C. Only 'Filtered Rows' step will be deleted

D. Nothing will change because you cannot delete middle steps

Solution

1. Step 1: Understand step dependencies

   Deleting a middle step removes that transformation; later steps recalculate based on remaining steps.

2. Step 2: Effect on later steps

   'Filtered Rows' depends on the data after 'Removed Columns'; it will recalculate using data without that removal.

3. Final Answer:

   'Removed Columns' step will be deleted, and 'Filtered Rows' will be recalculated without it -> Option B

4. Quick Check:

   Deleting middle step recalculates later steps [OK]

Hint: Deleting a step recalculates all following steps [OK]

Common Mistakes:

• Assuming all later steps delete automatically
• Thinking middle steps cannot be deleted
• Believing nothing changes after deletion

4. You accidentally removed a column in Power BI Query Editor but did not want to. Which of these is the best way to fix it?

medium

A. Create a new query from scratch

B. Close Power BI without saving and reopen the file

C. Manually add the column back using DAX

D. Undo the removal by deleting the 'Removed Columns' step in Applied Steps

Solution

1. Step 1: Identify the mistake step

   The 'Removed Columns' step is where the column was removed.

2. Step 2: Undo by deleting the step

   Deleting this step in Applied Steps will restore the column as if it was never removed.

3. Final Answer:

   Undo the removal by deleting the 'Removed Columns' step in Applied Steps -> Option D

4. Quick Check:

   Undo mistake by deleting step [OK]

Hint: Fix mistakes by deleting wrong Applied Steps [OK]

Common Mistakes:

• Closing without saving loses all work
• Trying to add columns with DAX instead of Query Editor
• Rebuilding query unnecessarily

5. You applied these steps in order:
1. Changed Type
2. Filtered Rows
3. Added Custom Column

Later you realize the 'Changed Type' step was incorrect. What is the best approach to fix this without losing your custom column?

hard

A. Delete the 'Changed Type' step and then reapply it correctly before the other steps

B. Delete all steps and start over from the source

C. Edit the 'Added Custom Column' step to fix the type issue

D. Ignore the error and proceed with the current steps

Solution

1. Step 1: Remove incorrect 'Changed Type' step

   Delete the wrong 'Changed Type' step to remove the incorrect data type changes.

2. Step 2: Reapply correct 'Changed Type' step before other steps

   Reapply the correct type changes before 'Filtered Rows' and 'Added Custom Column' to keep data consistent.

3. Final Answer:

   Delete the 'Changed Type' step and then reapply it correctly before the other steps -> Option A

4. Quick Check:

   Fix errors by correcting early steps without losing later ones [OK]

Hint: Fix early step errors by deleting and reapplying them [OK]

Common Mistakes:

• Deleting all steps loses work
• Editing later steps to fix early errors
• Ignoring errors causes wrong data