Question

我正在构建一个从订阅表中获取用户的函数。然后，这些用户将用于获取他们各自的文章并以有序的方式显示它们。

我设法做到了一半。它将获取用户，然后输出用户文章。但它一次只需要一个用户。我正在寻找一种方法来选择我的订阅表中的所有用户并将其全部取出，因此我可以同时显示它们，但按日期排序。

表格：

**Subscribe :** 
Lastviewed ( datetime ) 
Uniqueuser ( userid )
Subscription ( subscribed users id)

**Article:**
date_posted ( datetime )
uniqueuser ( users id)

这就是我得到的：

$sesname = $_SESSION['full_name'];
$sesid = $_SESSION['user_id'];

connectDB();
$sql ="select * from subscribe where uniqueuser = '$sesid'";
$rsd = mysql_query($sql);

while ($row = mysql_fetch_array($rsd))
{
    $subscription = $row['subscription'];
    $lastviewed = $row['lastviewed'];
    $substart = $row['substart'];
    $sql3 = "select * from article 
        where uniqueuser = '$subscription' 
        and date_posted > '$lastviewed' 
        order by date_posted 
        desc limit 0, 7";

    $rsd3 = mysql_query($sql3);
    $newarticles = mysql_num_rows($rsd3);

    while ($row3 = mysql_fetch_assoc($rsd3)) {
        $id  =$row3['id'];
        $title = $row3['title'];
        $uid = $row3['uniqueuser'];
        $sql2 = "SELECT * FROM users WHERE id = '$uid'";  
        $result2 = mysql_query($sql2);

        while ($row2 = mysql_fetch_assoc($result2)) {
            $name = $row2['user_name'];
            echo "<b><a>{$name}</a></b> wrote an <a>article</a><br>";
        }
    }
} //END SUBSCRIBE

输出：

User A wrote an article (1th july)
User A wrote an article (2th july)
User A wrote an article (3th july)
User A wrote an article (4th july)
User B wrote an article (1th july)
User B wrote an article (2th july)
User B wrote an article (3th july)
User B wrote an article (4th july)

即使用户B的文章已在用户A的帖子之间发布，它也会向一个用户一个接一个地命令。

通缉输出：

User A wrote an article (1th july)
User B wrote an article (1th july)
User A wrote an article (2th july)
User B wrote an article (2th july)
User A wrote an article (3th july)
User B wrote an article (3th july)
User A wrote an article (4th july)
User B wrote an article (4th july)

那么无论用户写的是什么，我如何将其组合并按日期排序？我认为我的问题是因为订阅查询的while循环，但我不知道任何其他方法来做到这一点。任何帮助是极大的赞赏！ =）

Answer 1

或多或少简单地加入所涉及的3个表并按 a.date_posted

排序

$sql2 = "select a.* , u.user_name, a.id as article_id, u.id as user_id 
    from subscribe s
    join article a on s.subscription = a.uniqueuser AND s.lastviewed < a.date_posted
    join user u on a.uniqueuser = u.id
    where s.uniqueuser = '$sesid'
    order by a.date_posted 
    desc limit 0, 7";

$result2 = mysql_query($sql2);

while ($row2 = mysql_fetch_assoc($result2)) {
    $name = $row2['user_name'];
    $date = $row2['date_posted'];
// fetch the columns having the same name using aliases
$a_id = $row2['article_id'];
$u_id = $row2['user_id'];

    echo "<b><a>{$name}</a></b> wrote an <a>article</a>({$date})<br>";
}

修改

修复条件s.lastviewed＆lt; a.date_posted

添加关于加入

两个或多个表之间的

连接是具有有效/真实条件（ON和WHERE）的表的所有元素的所有组合的集合

从多个用户获取行并按日期显示它们

1 个答案: