I was wondering if it is also possible to search for questions which are unanswered AND also lack any comments? I could not find it here or using Google.
You can only link the two databases containing
comments using the SEDE. The following query lists questions on the main site, sorted by their last activity date (oldest to newest) with these attributes:
select top 1000 p.id as [Post Link], p.lastactivitydate as [Last Active] from posts p left outer join comments c on c.postid = p.id where p.posttypeid = 1 -- Questions and c.id is null and answercount = 0 and p.score > 0 and closeddate is null order by lastactivitydate