In which I detail A SQL query that helps you identify files in a codebase that have “churned” in the past year. In other words, list the files that have been changed by the most number of commits in the last year.

SELECT file,
       COUNT(*)
FROM   stats
       JOIN commits
         ON stats.commit_id = commits.id
WHERE  commits.author_when > DATE('now', '-12 month')
       AND commits.parent_count < 2 -- ignore merge commits
GROUP  BY file
ORDER  BY COUNT(*) DESC
LIMIT  50