Background: I have a unique setup with multiple tables, each with circa 1,600 columns, which I am trying to clean up (it creates benefits upstream). I know that around 80% of these columns will always be [NULL] but I need to know precisely which ones (millions of rows).

I could do the following 1,600 times, but it seems very inefficient:

select max(column1) as 'column1'
,max(column2) as 'column2'
from mytable;

If it makes a difference, it’s Redshift (but I don’t have access to AWS).

So far, I have tried the above as a proof of concept, but it doesn’t scale well. So, my only other option is to copy and paste the headers into Excel using a transverse paste and then write a concat based on the numbers.

I appreciate any help you can provide otherwise – I will accept my fate 🙂