Exclude Fields with null value from table

[jt_yshi]

Hello Splunk Community,

I am looking for some help.

I would like to make an audit of all fields where there is not NULL for a given event. Which means I want a table with all fields where the vaule is not NULL. The thing is I do not want to have to specify the fields as there are too many and I am creating an audit of all fields that have values. It would take too much time to specify the field names in the search and or table. Hence, I am looking for a solution that lists all fields != NULL

I tried: 

|fillnull value="NULL"

|search NOT "NULL"
|table*

and many other searches with metadata, metasearch and audit commands. I cannot seem to find the right syntax to exclude fields with a given field value eg NULL or simply empty ones.

Thank you in advance for you help!!

best,

julia