Creating dataflows in Power BI - Complete Walkthrough

Introduction

Dataflows let you prepare and clean data once and reuse it in many reports. This saves time and keeps data consistent across your Power BI projects.

When you want to combine data from multiple sources into one clean table for all reports

When your team needs to share the same prepared data without copying it

When you want to automate data refreshes for your datasets

When you want to reduce repeated data cleaning steps in different reports

When you want to store data in the cloud for easy access and management

Steps

Step 1: Sign in

- Power BI Service (app.powerbi.com)

You see the Power BI workspace home screen

Step 2: Click

- Workspaces pane, select your workspace

Workspace content loads showing datasets, reports, dashboards

Step 3: Click

- Create button at top right

A menu appears with options like Report, Dataset, Dataflow

Step 4: Select

- Dataflow from the Create menu

Dataflow creation screen opens with option to add new entities

Step 5: Click

- Add new entities button

Data source selection screen appears

Step 6: Choose

- Your data source type (e.g., SQL Server, Excel, SharePoint)

Connection settings form appears for the selected source

Step 7: Enter

- Connection details and credentials

Data preview loads showing tables or files available

Step 8: Select

- Tables or files to include

Selected data loads into Power Query editor

Step 9: Apply

- Transformations in Power Query editor (e.g., remove columns, filter rows)

Data preview updates to show cleaned data

Step 10: Click

- Save & Close button

Dataflow is saved and listed in your workspace

Before vs After

Before

Workspace shows no dataflows and reports connect directly to raw data sources

After

Workspace lists a new dataflow with cleaned, combined data ready for reports

Settings Reference

Refresh settings

📍 Dataflow settings in workspace

Schedule automatic data updates for the dataflow

Default: Manual

Data source credentials

📍 Dataflow settings > Data source credentials

Authenticate access to the data source

Default: Depends on source

Linked entities

📍 Dataflow editor

Reuse entities from other dataflows to avoid duplication

Default: Enable

Common Mistakes

Not setting data source credentials correctly

Dataflow cannot refresh or access data without proper authentication

Always configure and test credentials in dataflow settings before saving

Creating duplicate dataflows for the same data

Leads to inconsistent data and extra maintenance work

Use linked entities to reuse existing dataflows instead of copying

Summary

Dataflows help prepare and clean data once for reuse in many reports

You create dataflows in Power BI Service by selecting data sources and applying transformations

Remember to set credentials and refresh schedules to keep data updated