Percentage calculation across rows

The issue is a calculation on a column while maintaining the other column of a source for filtering purposes.
I have a source table with some columns, and one of them is item_id.
I would like to calculate the percentage of rows that have item_id out of all the rows.
Obviously, I can make the calculation with the query:
Select count(item_id)/count(*) from table
BUT The tricky part is that I need to keep the other columns, to be able to segment by them, meaning I would like the calculation to be made by the visualization rather than the query. Is that possible?

Grafana v8.4.7