以下是重构后的内容:

SELECT dw_posts.ID, dw_posts.post_title, dw_posts.post_content
FROM dw_posts
INNER JOIN dw_term_relationships ON (dw_posts.ID = dw_term_relationships.object_id)
WHERE 1=1
AND (dw_term_relationships.term_taxonomy_id = 5)
AND dw_posts.post_type = 'post'
AND (dw_posts.post_status = 'publish')
GROUP BY dw_posts.ID
ORDER BY RAND()
LIMIT 0, 6;