Querying for name and rep of commenter and post OP using SEDE

Question

I am new to T-SQL and would greatly appreciate help on the following query on the Stack Exchange Data Explorer.

For a given comment I need to display the username and reputation of whoever posted the comment, and whoever posted the post that was commented on. For instance, comment 5245510:

Why not using isnan() from math.h? Any specially reason?

The result would be similar to:

commenter username   reputation   poster username   reputation 
Constantin           2,474        kp11              419

Answer 1

Here is the query:

SELECT
  CASE WHEN U.Id = P.OwnerUserId THEN 'Poster' ELSE 'Commenter' END AS [User],
  U.Id AS [User Link],
  U.Reputation AS [User Rep]
FROM Comments AS C
INNER JOIN Posts AS P
  ON P.Id = C.PostId
INNER JOIN Users AS U
  ON U.Id IN (P.OwnerUserId, C.UserId)
WHERE C.Id = ##CommentId:int##

Link: https://data.stackexchange.com/stackoverflow/query/180387/name-and-rep-of-commenter-and-op-for-comment-id

Enter the comment ID in the box near the Run Query button.