php - MYSQL语法错误

Question

每次我尝试在 phpMyAdmin 中运行此 MYSQL 语句时，我都会收到此语法错误:

1064 - You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'comments,last_comment, '%d/%m/%Y %H:%i:%s') ASlast_comment FROMposts' at line 7

代码:

"SELECT
                `posts`.`post_id` AS `id`,
                `posts`.`post_title` AS `title`,
                LEFT(`posts`.`post_body`, 512) AS `preview`,
                `posts`.`post_user` AS `user`,
                DATE_FORMAT(`posts`.`post_date`,'%d/%m/%Y %H:%i:%s') AS `date`,
                `comments`.`total_comments`,
                DATE_FORMAT(`comments`.`last_comment`, '%d/%m/%Y %H:%i:%s') AS `last_comment`
            FROM `posts`
            LEFT JOIN (
            SELECT
                `post_id`,
                COUNT(`comment_id`) AS `total_comments`,
                MAX(`comment_date`) AS `last_comment`
            FROM `comments`
            GROUP BY `post_id`  
            ) AS `comments`
            ON `posts`.`post_id` = `comments`.`post_id`
            ORDER BY `posts`.`post_date` DESC";

此外，所有表的名称都正确。所以，这可以排除。

更新:

太棒了，谢谢。我在评论中添加了引号，多余的周长是句号而不是逗号。

Answer 1

DATE_FORMAT() 接受两个参数，而不是三个。 See the manual.

我想，你的意思是

`comments`.`total_comments`

代替？