WP SQL – Delete all post revisions and their metadata

Post revisions is an useful feature, but if you don’t delete the many revisions from time to time your database will quickly become very big. The following query deletes all post revisions as well as all the metadata associated with the revisions.

DELETE a,b,c
 FROM wp_posts a
 LEFT JOIN wp_term_relationships b ON (a.ID = b.object_id)
 LEFT JOIN wp_postmeta c ON (a.ID = c.post_id)
 WHERE a.post_type = ‘revision’ ;

→ Source: http://www.onextrapixel.com/2010/01/30/13-useful-wordpress-sql-queries…