Counts the number of popular (score 90%ile) reddit comments in active subreddits from the June 2018 reddit comment database hosted on google bigquery

popular_reddit_comment_removal.sql

WITH active_subreddits AS (SELECT subreddit, COUNT(subreddit) AS comments 
                           FROM `fh-bigquery.reddit_comments.2018_06` 
                           GROUP BY subreddit 
                           HAVING comments > 1000),
     p90_threshold     AS (SELECT subreddit, score,
                            CASE WHEN body = '[removed]' THEN 1 ELSE 0 END AS removed,
                            PERCENTILE_DISC(score, 0.9) OVER(PARTITION BY subreddit) AS percentile_90
                           FROM `fh-bigquery.reddit_comments.2018_06`),
     events            AS (SELECT subreddit, removed, percentile_90,
                            CASE WHEN score > 1 THEN 1 ELSE 0 END AS up,
                            CASE WHEN score < 1 THEN 1 ELSE 0 END AS down,
                            CASE WHEN score > 1 AND removed = 1 THEN 1 ELSE 0 END AS removed_up,
                            CASE WHEN score < 1 AND removed = 1 THEN 1 ELSE 0 END AS removed_down,
                            CASE WHEN score > percentile_90 THEN 1 ELSE 0 END AS count_percentile_90,
                            CASE WHEN score > percentile_90 AND removed = 1 THEN 1 ELSE 0 END AS removed_up_percentile_90
                           FROM p90_threshold
                           WHERE subreddit IN( SELECT subreddit FROM active_subreddits ) )


SELECT subreddit,
  COUNT(subreddit) AS comments, 
  SUM(up) as ups, 
  SUM(down) as downs, 
  SUM(removed) as removeds, 
  SUM(removed_up) as removed_ups, 
  SUM(removed_down) as removed_downs,
  MAX(percentile_90) as thresh_90_percentile,
  SUM(count_percentile_90) as ups_90_percentile,
  SUM(removed_up_percentile_90) as removed_ups_90_percentile
FROM events
GROUP BY subreddit