Finding the empty NOT IN () statement on the previous page esthetically unpleasing, I created an extra rule so it can be replaced with the also empty but better looking EXISTS() expression.
This is just a manner of appearance. Statements in EXISTS subqueries are linked to the main query in their filter and this implementation of Else Logic currently does not support syntax that differentiates between data in the main query and the subquery. As the data sources in FROM * do not get a name that differentiates them from the data sources in the main query, they cannot be used in an EXISTS expression. As a result Else Logic is not used with EXISTS subqueries.
The experiment of the previous experiment:
"show for January: the apple sales with the pear sales for departments not selling apples"