Views filter by taxonomy if not empty I would like to filter views block content by taxonomy. I have multiple content types on same block, and only one of them has taxonomy. The goal is to output all the nodes from content types with no taxonomy, and from certain term if content type has taxonomy.

Shorter: If content type has taxonomy, filter by it.

And not to be too simple: taxonomy is hierarchical and I would like to it work so, that nodes in child taxonomy would also appear when filtering by parent.

I could of course filter all the other terms out, but the thing is that client can add terms by himself. Therefore limiting the terms out manually is not the best solution.

I am using Drupal 7.22 and Views 3.7.
Use the views filter condition OR groups. Also make sure that the taxonomy relationship optional (uncheck Require this relationship).