Large dataset refresh issue, changed column name

[Marcinvelcino]

Hi,

I have a large (around 9.5 gb) dataset published to Power BI service. I got an error when tried to refresh : The 'ColumnA' column does not exist in the rowset. I checked and currently in source (sql serwer) the column name is ColumnB. 

The problem is that I don't have currently access to pbix file on my desktop to refresh it and re-publish and for this size I am also not able to download file from service. 

I tried and XMLA endpoint connection (the Workspace is premium) using tabular editor and change column name to ColumnB. It worked and I see the new column name in model, but the refresh issue remains. 

There are no others steps is Power Query for this table, only those defualt after load without transformation. 

[Marcinvelcino · Accepted solution]

I managed to fix the issue by editing "Source column" property in tabular editor connecting to XMLA endpoint.  After I set a proper column name the refresh went fine. 

[NZPowerBIGuy]

Thank you so much! Been trying to find a solution for this for a couple of days now.

[123abc]

Changing column names in Power BI datasets, especially for large datasets, can be tricky, especially if the changes are not synchronized with the source. It seems that you've encountered an issue where the column name in Power BI doesn't match the source, and you're unable to refresh the dataset due to the size constraints. Here are some steps to help address this issue:

1. **Power Query Editor (Power BI Desktop)**:
- If you can gain access to the Power BI Desktop file (PBIX), you should open it and use the Power Query Editor to change the column name directly within Power BI Desktop. This is the most straightforward and recommended approach.

2. **Direct Source Access**:
- If you have access to the SQL Server and can change the column name back to 'ColumnA' to match what's in the Power BI dataset, that would be the ideal solution. Once the source matches the dataset, you should be able to refresh it without errors.

3. **XMLA Endpoint (Tabular Editor)**:
- Since you've already tried using Tabular Editor to change the column name to 'ColumnB,' here are some additional steps you can follow:
- Save your changes in Tabular Editor.
- Go to the Power BI Service.
- In the dataset settings in the Power BI Service, check if you have the "Allow schema modification" setting enabled. This setting allows schema changes like column renaming.
- Trigger a dataset refresh from the Power BI Service. This should apply the schema changes from Tabular Editor.
- After the refresh, you can then go back to the source and change the column name to 'ColumnA.'
- Finally, refresh the dataset again to ensure it matches the source.

4. **Recreate Dataset (Last Resort)**:
- If none of the above steps work, you might have to consider recreating the dataset from scratch in Power BI Desktop with the correct column names and then republishing it to the Power BI Service. This should be a last resort due to the large dataset size.

5. **Contact Support**:
- If you've exhausted all options and still can't resolve the issue, consider contacting Power BI support. They may be able to provide specific guidance or assistance for your situation.

Please exercise caution when making schema changes in a production dataset, especially if it's a large dataset. Always ensure you have proper backups and a clear plan for recovery in case anything goes wrong during the process.