[wp-hackers] Recent Comments Plugins.

[Denis de Bernardy]

> It's probably a case where two queries would be better than one:

Or, more likely, where the aggregate is useless:

SELECT
  posts.*
FROM
  wp_posts as posts
INNER JOIN
  wp_comments as comments
    ON comments.post_ID = posts.ID
WHERE
  comments.comment_approved = '1'
  # and whatever else
GROUP BY
  posts.ID # prevent a post to appear twice
ORDER BY
  comments.comment_date DESC # works too
LIMIT 0,20


> mysql> EXPLAIN SELECT wp_posts . * , MAX( comment_date ) AS 
> mysql> max_comment_date
>      -> FROM wp_comments, wp_posts
> WHERE wp_posts.post_date <= '2005-07-19 13:38:31'
>      -> WHERE wp_posts.post_date <= '2005-07-19 13:38:31'
>      -> AND (
>      -> wp_posts.post_status = 'publish'
>      -> OR wp_posts.post_status = 'sticky'
>      -> )
>      -> AND wp_posts.post_password = ''
>      -> AND wp_posts.ID = wp_comments.comment_post_ID
>      -> AND wp_comments.comment_approved = '1'
>      -> GROUP BY wp_posts.ID
>      -> ORDER BY max_comment_date DESC
>      -> LIMIT 0 , 20;