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POPHP and MySQL, what's wrong with this function?
 

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  1. POPHP and MySQL, what's wrong with this function?
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    <p>This function doesn't work and I can't find the problem, which is somewhere inside the query.</p> <pre><code>function get_category_posts($category, $page, $per_page) { $start = (int)($page - 1) * $per_page; $per_page = (int)$per_page; $sql = "SELECT `posts`.`post_id` AS `id`, `posts`.`post_title` AS `title`, `posts`.`post_category` AS `category`, `posts`.`post_body` AS `preview`, `posts`.`post_user` AS `user`, DATE_FORMAT(`posts`.`post_date`, '%Y-%m-%d %H:%i:%s') AS `date`, `comments`.`total_comments`, DATE_FORMAT(`comments`.`last_comment`, '%Y-%m-%d %H:%i:%s') AS `last_comment` FROM `posts` WHERE `category`='".$category."' 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 LIMIT {$start}, {$per_page}"; $posts = mysql_query($sql); //die(mysql_error()); $rows = array(); while (($row = mysql_fetch_assoc($posts)) !== false) { $rows[] = array( 'id' =&gt; $row['id'], 'title' =&gt; html_entity_decode($row['title']), 'category' =&gt; html_entity_decode($row['category']), 'preview' =&gt; html_entity_decode($row['preview']), 'user' =&gt; html_entity_decode($row['user']), 'date' =&gt; $row['date'], 'total_comments' =&gt; ($row['total_comments'] === null) ? 0 : $row['total_comments'], 'last_comment' =&gt; ($row['last_comment'] === null) ? 'aldrig' : $row['last_comment'] ); } return $rows; </code></pre> <p>} The function works fine without the <code>WHERE</code>category<code>='".$category."'</code>, however, with it it returns </p> <blockquote> <p>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 'LEFT JOIN ( SELECT <code>post_id</code>, COUNT(<code>comment_id</code>) AS <code>total_comments</code>, ' at line 12</p> </blockquote>
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    1. USPeter Jonsson
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