Some more searching here turned up this post that seems to cover it:
https://forum.kodi.tv/showthread.php?tid...pid3116055
Go into Edit->Settings->Miscellaneous->Media List Editor
Next to 'CREATE VIEW' enter a name you want to use to select this from the Filters section List drop-down. I called mine "missing_actors"
Put this in the text box below:
sql:
SELECT DISTINCT
movielist.*
FROM
movielist
LEFT OUTER JOIN actorlinkmovie ON (actorlinkmovie.idMovie = movielist.idMovie)
GROUP BY
movielist.idMovie
HAVING COUNT(actorlinkmovie.idMovie) = 0
Press the [+ Add] button. And then OK the settings and get back your list of movies.
The the Filters section (at the bottom left) select the List drop-down and you'll see the view you created above (again, I called mine 'missing_actors').
Basically we're combining two database tables into a view. One table that has the movies, joined against another table of actors with that same id (but with zero records). As in, are there any movies that don't have any actors linked?