Purpose of this post (what type of answers do I expect)
This post is meant to get answers in the form of one or more links to Stack Exchange Data Explorer queries which list comments that are unnecessary. Ideally the comments are sorted so that more important cases appear first (if everyone starts flagging the comments starting at the top of the list, those important cases are removed first).
Sorting by importance can be done in multiple ways, each have their own up- and downsides (this is a non-exhaustive list, numbers are for referencing only, it's not an order of preference):
By date, oldest first (top results don't change until comment is deleted, but comments are probably not read as much today)
By date, newest first (top results keep changing, but those comments are probably read because they are likely to be on newer posts)
By view count of question, highest first (top results don't change)
By comment length, shortest comments first
Please include links to your proposed queries on data.stackexchange. Also indicate what the query returns, i.e. which types of comments it looks for and how they are sorted.
Please note that if you don't log in you need to complete a Captcha to run the queries, that restriction is lifted when you log in with standard SE credentials.
Scope of comments
The comments I think of that could be found this way are:
Comments which only express gratitude (i.e. small number of characters, containing things like 'thx', 'thanks', 'ty', et cetera).
Vulgar language aimed at other users (link to question on offensive comments)
Junk(this is a broad category)
For a more exhaustive list on unwanted comments, see the help centre page on comments
Rewards
First of all, removing unnecessary comments provides everyone with a better experience. In addition to that, there are some rewards in the form of badges for those who systematically flag (awards on 5th of april 2018 in brackets):
- Citizen patrol: first flagged post (3609 awards)
- Deputy: raise 80 helpful flags (152 awards)
- Marshal: raise 500 helpful flags (38 awards)
Furthermore, the number of flags at your disposal every day will increase as well, the number is given by this formula:
Max(100, 10+Floor(reputation/2000) + Floor((helpful flags - declined flags)/10))