Power Query Editor is the data preparation engine of Power BI. It allows you to clean, transform, and shape raw data before it is loaded into the data model.
? Key Concepts
Power Query works on a step-based transformation system
All actions are recorded as Applied Steps
Uses M language internally (auto-generated)
Data is prepared before reporting and DAX
? What is Power Query Editor?
Power Query Editor is the environment where raw data is cleaned and standardized. It ensures correct data types, removes errors, and structures data properly for analysis.
? How to Open Power Query Editor
Open Power BI Desktop
Click Home → Get Data
Select the data source
Click Transform Data
? Power Query Editor UI
Ribbon: Cleaning and transformation tools
Queries Pane: List of tables
Data Preview: Table data view
Applied Steps: Transformation history
? Step-Based Transformation System
Every change you make is saved as a step. Steps can be edited, deleted, or reordered to control data flow.
? Data Types
Text
Whole Number
Decimal Number
Date
? Data Type Example
// Numbers incorrectly stored as text
"1000"
"2500"
"4300"
?️ Remove Column
Select the column
Right-click → Remove
✂️ Remove Rows
Remove Top Rows
Remove Bottom Rows
Remove Blank Rows
? Applied Steps
Applied Steps track every transformation applied to data. This ensures transparency and repeatability.
? Use Cases
Cleaning Excel and CSV files
Standardizing data from multiple sources
Removing junk rows and columns
Preparing data for DAX calculations
⚡ Interactive Power Query Simulator
Apply transformations to see how "Applied Steps" work.