WP Delete posts older than x days

DELETE a,c
FROM wp_posts a
LEFT JOIN wp_postmeta c ON ( a.ID = c.post_id )
WHERE a.post_type = 'post'
AND DATEDIFF(NOW(), a.post_date) > 300


Delete posts from x category
------------
DELETE a,b,c,d
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 )
LEFT JOIN wp_term_taxonomy d ON ( d.term_taxonomy_id = b.term_taxonomy_id )
LEFT JOIN wp_terms e ON ( e.term_id = d.term_id )
WHERE e.term_id=2174

cron job
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wget --quiet --spider "URL_TO_FILE"