我正在做一个从某人的定制CMS到WP安装的特殊迁移。我成功地将帖子和评论迁移到各自的表中。现在，我需要将每个匹配id的评论计数放入wp\\u posts表中。我很接近，我想：

SELECT COUNT(comment_content) AS total_comments, comment_post_ID AS commentID
FROM wp_comments
GROUP BY comment_post_ID;
--mysql won\'t let me run the group by on just the returned count column, so I\'m stuck with    two columns of data when I just want to insert one

UPDATE wp_posts SET comment_count = total_comments WHERE wp_posts.ID = commentID;
--So I tried to set my returned data to variables and assign them into the update statement..which doesn\'t work

无论如何，也许我需要迭代所有帖子，找到一个匹配的ID，然后通过移动光标来更新它？还是有更简单的方法让我错过了？

    UPDATE wp_posts, (SELECT COUNT(comment_content) AS total_comments, comment_post_ID
FROM wp_comments
GROUP BY comment_post_ID) x
       SET wp_posts.comment_count = x.total_comments
       WHERE wp_posts.ID = x.comment_post_ID;