Columnar table and NULL values - space savings or no?

Aster
Enthusiast

Columnar table and NULL values - space savings or no?

Just curious: If I had a columnar table, and one of the columns was usually NULL, would there be any space savings over a row-oriented table with the same set of columns and data?

(Note: I realize that it would be better to simply not have that column.  I'm asking a hypthetical question and trying to make its terms clearer.)