How to Add a New Column to an Existing Power Query Without Breaking the Report?

This is really dependent on your data model and how much data you're actually bringing in. When you say it breaks the enitre setup trying to add one column, can you share an example of the error you're getting?

If this is just a one-off column that you need to add I'd probably add it as a calculated column with DAX as a quick fix.

sirbaklava give this a try, and if you encounter any issues, let me know.

1. Open Power Query Editor.
2. Identify the step where you need the new column.
3. Add the column using "Add Column" options, or adjust the source step to include it.
4. Refresh the data and validate the report.

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