Question

我对PHP和SQL比较陌生，而且我正在为自己的页面创建一个简单的博客工具，而且我仍然坚持如何制作评论部分。我有2张桌子 general，其中包含博客文章和其他信息评论，其中包含评论

$servername = "localhost";
$username = "root";
$password = "password";
$dbname = "blog";
$conn = new mysqli($servername, $username, $password, $dbname);
if ($conn->connect_error){
    die ("connection failed: " . $conn->connect_error);
}
$sql = "SELECT * FROM general WHERE hidden = 'false' ORDER BY id DESC";
$result = $conn->query($sql);
if ($result->num_rows > 0){
   while ($row = $result->fetch_assoc()){
     echo "<div class='blogpost'>
          <div class='blogbody'></div>";

     //I need to do a query into the comments table at this point to find
     //all comments matching the criteria to be matched with the post here.
     echo "<div class='comments'></div></div>";
   }
}
else{
    echo "no posts";
}

我设法让博客文章正常工作，但是一旦我通过添加

尝试第二次查询

$conn2 = new mysqli($servername, $username, $password, $dbname);
if ($conn2->connect_error){
    die ("connection failed: " . $conn2->connect_error);
}
$sql2 = "SELECT * FROM comments WHERE $row["parent"] ORDER BY id DESC";
$result2 = $conn2->query($sql2);
if ($result2->num_rows > 0){
    while ($row2 = $result2->fetch_assoc()){

    }
}
else{
    echo "no comments";
}

一切都好了。在开始加载其他帖子之前，我无法引入一个获取特定帖子所有评论的循环。

我将如何继续解决这个问题？我可能需要在任何代码示例中添加一些带有注释的勺子，

Answer 1

您可以使用帖子的主键，并且可以在评论表中将其用作外键，这样您就可以轻松地使用该键来显示针对该特定帖子的所有评论。然后查询将是这样的：

 $postid=$row['post_id'];

$ sql2 =“SELECT * FROM comments WHERE post_id ='$ postid'ORDER BY post_id DESC”;

Answer 2

更改第二个查询以解决问题。

WHERE $row["parent"] ORDER. Change that to WHERE parent={$row['parent']} ORDER

感谢Jeff提供此答案

使用PHP从2个表中选择数据

2 个答案: