How to order search results based on author field content
You are almost have done it.

I made a relationship between the content and the author. I can access field &quot;x&quot; in the fields part of views, but it does not show up in the &quot;filter&quot; or &quot;order by&quot; parts.

add that fix &quot;X&quot; in sort section and sort it as Descending. when you make it descending contents with null values appear after those that have value.