Unpivot All Columns Except Key Columns in Power Query M

Notes

List every column that should stay as-is in KeyColumns; everything else becomes Attribute/Value pairs.

Requirements

• A table with one or more identifier columns and any number of value columns.

How to use this snippet

1. In Power BI Desktop, choose Transform data to open Power Query, then open the Advanced Editor on a query (or start from a blank query).
2. Paste the snippet and replace the placeholder names (tables, columns, file paths) with your own. Check the requirements above first.
3. Run it through the Power Query M Formatter to tidy the layout.

Related Power Query M snippets

• Unpivot ColumnsTurns wide columns (like one column per month) into Attribute/Value pairs.
• Unpivot Month ColumnsUnpivots only the columns that look like month names, leaving key columns like ID or Region untouched.
• Promote Headers and Remove Top N RowsSkips a fixed number of junk rows at the top of a source (common in exported reports) before promoting the real header row.
• Pivot ColumnsTurns unique values from one column into separate columns, aggregating another column.
• Pivot Without AggregationPivots a column into new columns while keeping the raw values, for cases where each group only has one row per pivoted category.
• Transpose Table and Keep HeadersFlips rows and columns while preserving the original column names as a new first row.

More Power Query M resources

Browse all 145 snippets in the Power Query M Code Snippets, or search the library for something similar to Unpivot All Columns Except Key Columns.