Re: assistance with a DELETE query using an IN subquery

[Peter Brawley]

With a batch deletion query like that, it's often safer to run the SELECT version of the query and study the results before running the DELETE.

SELECT a.*
FROM wp_posts a
JOIN (
  SELECT post_title, MAX(post_date) AS latest
  FROM wp_posts 
  WHERE post_type = "revision" 
  GROUP BY post_title
) b OB a.post_title=b.post_title and a.post_date<b.latest;