You can add comments to your code either with single-line comments that start with ‘//’ or multi-line comments that start with ‘/*’ and end with ‘*/’.
Adding Comments In M With Power Query
Let’s take an example to see how it works.
Step 1: Load Data in Power Query
Load the data in Power Query first to apply comments in M as shown below. Perform some action to the data table loaded in Power Query. Here we have merged the columns.
Step 2: Open Advanced Editor
To open Advanced Editor in Power Query click on
Home > Advanced Editor
Step 3: Add Comments in M
Add a single comment to the query for merging columns in Advanced Editor dialogue box as shown below. We have added the comment //Merge Columns to the Advanced Editor.
Step 4: Close & Apply
The picture below shows the data table after merging the columns and adding comments in Query Editor. Now you can close and apply the changes.
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