Power BI Practice: Centralizing Excel Data Source References in Power BI Using Power Query M

Scenario:

You create a parameter named DataSourceExcel that holds the file name and location of a Microsoft Excel data source. You need to update the query to reference the parameter instead of multiple hard-coded copies of the location within each query definition.

Solution: In the Power Query M code, you replace references to the Excel file with DataSourceExcel. Does this meet the goal?

Answer: Yes, this solution meets the goal. By replacing the hard-coded references to the Excel file with the DataSourceExcel parameter in your Power Query M code, you centralize the file path and name information. This makes it easier to manage and update the data source location, ensuring consistency across all queries.

Step-by-step guide

Step 1: Open Power BI Desktop

• Launch Power BI Desktop and open your report.

Step 2: Go to Power Query Editor

• Click on Home in the ribbon.

• Select Transform data to open the Power Query Editor.

Step 3: Create a Parameter

• In the Power Query Editor, go to the Home tab.

• Click on Manage Parameters and select New Parameter.

• Name the parameter DataSourceExcel.

• Set the type to Text.

• Enter the file path and name of your Excel data source in the Current Value field.

• Click OK.

Step 4: Create a New Query

• Go to the Home tab.

• Click on New Source and select Blank Query.

Step 5: Reference the Parameter in the Query

• In the formula bar, enter the following M code to reference the parameter:

let Source = Excel.Workbook(File.Contents(DataSourceExcel), null, true) in Source

This code uses the DataSourceExcel parameter to dynamically reference the Excel file.

Step 6: Load Data from Excel

• After referencing the parameter, you will see the contents of the Excel file.

• Select the desired sheet or table from the workbook.

• Click Close & Load to load the data into Power BI.

Step 7: Update Existing Queries

• If you have existing queries that hard-code the file path, update them to use the DataSourceExcel parameter instead. For example, replace:

let Source = Excel.Workbook(File.Contents("C:\path\to\your\file.xlsx"), null, true) in Source

with:

let Source = Excel.Workbook(File.Contents(DataSourceExcel), null, true) in Source

Benefits • Centralized Management: Any changes to the file path or name only need to be updated in the parameter.

• Consistency: Ensures all queries reference the same data source location.