我有一个类别页面,它们在进行联接之前运作正常。类别的显示如下:
category 1-----------------------0----------0 discussion 1 by someone category 2-----------------------0----------0 discussion 2 by someoneelse 现在,在讨论处,我需要根据其“discussion_id”显示发布到该类别的最后一篇讨论。我尝试了“ORDER BY ... DESC”,但它按类别名称而不是讨论名称和发布者进行排序。
category 1-----------------------0----------0 discussion 1 by someone category 2-----------------------0----------0 discussion 2 by someoneelse 现在,在讨论处,我需要根据其“discussion_id”显示发布到该类别的最后一篇讨论。我尝试了“ORDER BY ... DESC”,但它按类别名称而不是讨论名称和发布者进行排序。
$sql = "SELECT *, COUNT(d.cat_id) as count
FROM discussions as d
LEFT JOIN categories c ON (c.cat_id = d.cat_id)
RIGHT JOIN soldiers s ON (s.uid = d.discussion_poster)
GROUP BY d.cat_id";
$result = query($sql);
while (($row = mysqli_fetch_assoc($result)) != false) {
$cat_id = $row['cat_id'];
$discussion_id = $row['discussion_id'];
$cat_title = $row['cat_title'];
$discussion_title = $row['discussion_title'];
$discussion_time = $row['discussion_time'];
$count = $row['count'];
$discussion_poster_id = $row['discussion_poster'];
$discussion_poster = $row['soldier'];
}