SQL Query to Return Number of Distinct Values for Each Column

Question

For background, I am querying a large database with hundreds of attributes per table and millions of rows. I'm trying to figure out which columns have no values at all.

I can do the following:

SELECT
COUNT(DISTINCT col1) as col1,
COUNT(DISTINCT col2) as col2,
...
COUNT(DISTINCT coln) as coln
FROM table;

Whenever a count of 1 is returned, I know that column has no values, great. The issue is that this is incredibly tedious to retype hundreds of times. How can I do this in a more efficient manner? I only have a fundamental understanding of SQL, and the limited capabilities of Athena makes this more difficult for me. Thank you

Edit: Just to clarify, the reason why the count needs to be 1 is because this database uses empty Strings rather than NULL