Skip to main content
cancel
Showing results for 
Search instead for 
Did you mean: 

To celebrate FabCon Vienna, we are offering 50% off select exams. Ends October 3rd. Request your discount now.

Reply
Baskar
Resident Rockstar
Resident Rockstar

Formula.Firewall: (step 'Invoked Custom Function') references other queries

Thanks Advanced.

 

Dear community friends,

 

I have spend more then 10 days on this issue, but my badluck still working for solution.

Issue : 

       Formula.Firewall: Query 'Flow Main (2)' (step 'Invoked Custom Function') references other queries or steps, so it may not directly access a data source. Please rebuild this data combination.

 

Source : 

1. Tabular Cube [ Table1,Table2]

2. OLE BD function.

 

Pulling dta into OLE DB connection from Tabular cube with paramater to populate data.

 

Step 1:

  Createing dataset from Tabular with merging Table1 and Table2.

Step 2:

  Created function using OLE DB with paramater.

Step 3:

  Created refrence of the Step 1 and used Invoke function (Step 2 function) to get data.Here is the place am getting this error.

Formula.Firewall: Query 'Flow Main (2)' (step 'Invoked Custom Function') references other queries or steps, so it may not directly access a data source. Please rebuild this data combination.

 

Note :

   I can't ignore the privacy policy from settings.

 

@ImkeF @MattAllington 

5 REPLIES 5
v-frfei-msft
Community Support
Community Support

Hi @Baskar,

 

Based on my test, I can reproduce a similar error as yours. Clearly we cannot combine an external data source with another query. Please check the blog to solve your issue.

 

1.png

At first, I create a parameter that contains file path/name and let the source is equal to the parameter. Then the M code is like this.

 

let
    Source = Folder.Files(Parameter1),
    #"Invoke Custom Function1" = Table.AddColumn(Source, "Transform File from C (2)", each #"Transform File from C (2)"([Content])),
    #"Renamed Columns1" = Table.RenameColumns(#"Invoke Custom Function1", {"Name", "Source.Name"}),
    #"Removed Other Columns1" = Table.SelectColumns(#"Renamed Columns1", {"Source.Name", "Transform File from C (2)"}),
    #"Expanded Table Column1" = Table.ExpandTableColumn(#"Removed Other Columns1", "Transform File from C (2)", Table.ColumnNames(#"Transform File from C (2)"(#"Sample File (2)"))),
    #"Changed Type" = Table.TransformColumnTypes(#"Expanded Table Column1",{{"Source.Name", type text}, {"ID", Int64.Type}, {"name", type text}}),
    #"Merged Queries" = Table.NestedJoin(#"Changed Type",{"name"},#"Transform Sample File from C",{"name"},"Transform Sample File from C",JoinKind.LeftOuter)
in
#"Merged Queries"

And based on the above blog, I take the steps and change the M code as below.

 

let
    Source = testlist,
    #"Invoke Custom Function1" = Table.AddColumn(Source, "Transform File from C (2)", each #"Transform File from C (2)"([Content])),
    #"Renamed Columns1" = Table.RenameColumns(#"Invoke Custom Function1", {"Name", "Source.Name"}),
    #"Removed Other Columns1" = Table.SelectColumns(#"Renamed Columns1", {"Source.Name", "Transform File from C (2)"}),
    #"Expanded Table Column1" = Table.ExpandTableColumn(#"Removed Other Columns1", "Transform File from C (2)", Table.ColumnNames(#"Transform File from C (2)"(#"Sample File (2)"))),
    #"Changed Type" = Table.TransformColumnTypes(#"Expanded Table Column1",{{"Source.Name", type text}, {"ID", Int64.Type}, {"name", type text}}),
    #"Merged Queries" = Table.NestedJoin(#"Changed Type",{"name"},#"Transform Sample File from C",{"name"},"Transform Sample File from C",JoinKind.LeftOuter)
in
#"Merged Queries"

Then we can get the result without no issue. If you still get errors, please share your Power Query code here.

 

Regards,

Frank

Community Support Team _ Frank
If this post helps, then please consider Accept it as the solution to help the others find it more quickly.

Thanks for your response @v-frfei-msft.

 

Here i have to use invoke function to get data from OLE DB connection. It is PI source.

 

Baskar
Resident Rockstar
Resident Rockstar

@ImkeF Any input for this issue.

ImkeF
Community Champion
Community Champion

Hi @Baskar,

I can only refer to the link that @v-frfei-msft has given as well: https://www.excelguru.ca/blog/2015/03/11/power-query-errors-please-rebuild-this-data-combination/

 

You have to re-structure your queries accordingly.

Imke Feldmann (The BIccountant)

If you liked my solution, please give it a thumbs up. And if I did answer your question, please mark this post as a solution. Thanks!

How to integrate M-code into your solution -- How to get your questions answered quickly -- How to provide sample data -- Check out more PBI- learning resources here -- Performance Tipps for M-queries

Baskar
Resident Rockstar
Resident Rockstar

Firewall Issue.GIF

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

@ImkeF @v-frfei-msft i have followed the link but still am getting same error.

Here i have attached my flow diagram.

My source is SSAS.

1. CT_1 ans PI Tags are two different DAX code.

2. Mergeing this two dataset to create Merge1 step.

 

Here am trying to invokle my PI function.

 

@MarcelBeug can you please help me on this case

Helpful resources

Announcements
September Power BI Update Carousel

Power BI Monthly Update - September 2025

Check out the September 2025 Power BI update to learn about new features.

August 2025 community update carousel

Fabric Community Update - August 2025

Find out what's new and trending in the Fabric community.

Top Kudoed Authors