Php 试图显示两个表中的数据
我正试图根据在另一个表中找到的id从一个表中获取数据。我的第一个表格叫做Php 试图显示两个表中的数据,php,mysql,Php,Mysql,我正试图根据在另一个表中找到的id从一个表中获取数据。我的第一个表格叫做user\u thinks，这个表格保存了用户在我的“社交媒体网站”上发表的所有公开帖子的数据。我还有一个名为users的表，它存储了站点注册用户的所有详细信息 我试图在网站主页上显示所有用户的想法，但我正在努力为“想法”的作者显示正确的数据 其思想是获得用户思想的添加的（作者），然后使用持有添加的值的变量，并将其与用户表中的用户名进行比较 以下是我的表格及其字段： 用户想法： id message date_of_msg_
user\u thinksusers用户的想法用户思想的添加的（作者），然后使用持有添加的值的变量，并将其与用户表中的用户名进行比较
以下是我的表格及其字段：
用户想法
：
id
message
date_of_msg_post
time_of_msg_post
attachment
added_by
/* How it works: The id of each user_thought will be used to determine which user posted it.
* Then display their details accourdingly.
*/
$get_thoughts_from_db = mysqli_query($connect, "SELECT * FROM user_thoughts ORDER BY id DESC"); // newest posts first
while ($row = mysqli_fetch_assoc($get_thoughts_from_db)) {
$thought_id = $row['id'];
$msg_content = $row['message'];
$date_of_msg = $row['date_of_msg_post'];
$thoughts_by = $row['added_by'];
$time_of_msg = $row['time_of_msg_post'];
$attachent = $row['attachment'];
$get_user = $_GET['id'];
} // while closed
// Get the details of the user based on the ID of the user thought.
$get_data = mysqli_query($connect, "SELECT * FROM users WHERE id = '$get_user'");
$get_user_data = mysqli_fetch_assoc($get_data);
$author_fname = $get_user_data['first_name'];
$user_profile_dp = $get_user_data['profile_pic'];
// displaying all the posts in the database on the main page.
// Will limit 15 posts per page, and will order them by the date and time posted (latest posts first)
$get_all_posts_q = mysqli_query ($connect, "SELECT * FROM user_thoughts ORDER BY id DESC ");
$check_rows = mysqli_num_rows($get_all_posts_q);
while ($get_row = mysqli_fetch_array($get_all_posts_q)){
$message = $get_row['message'];
/**** Between the while loop is where I echo the div(s)
which display the above details. *******/
}
用户
（仅显示相关字段）
Aim：从user\u thinks
获取帖子的added\u by，然后使用added\u by从表users
中的username字段获取added\u by的详细信息。注意：added_by和username将保留相同的值
以下是我尝试过的：
id
message
date_of_msg_post
time_of_msg_post
attachment
added_by
/* How it works: The id of each user_thought will be used to determine which user posted it.
* Then display their details accourdingly.
*/
$get_thoughts_from_db = mysqli_query($connect, "SELECT * FROM user_thoughts ORDER BY id DESC"); // newest posts first
while ($row = mysqli_fetch_assoc($get_thoughts_from_db)) {
$thought_id = $row['id'];
$msg_content = $row['message'];
$date_of_msg = $row['date_of_msg_post'];
$thoughts_by = $row['added_by'];
$time_of_msg = $row['time_of_msg_post'];
$attachent = $row['attachment'];
$get_user = $_GET['id'];
} // while closed
// Get the details of the user based on the ID of the user thought.
$get_data = mysqli_query($connect, "SELECT * FROM users WHERE id = '$get_user'");
$get_user_data = mysqli_fetch_assoc($get_data);
$author_fname = $get_user_data['first_name'];
$user_profile_dp = $get_user_data['profile_pic'];
// displaying all the posts in the database on the main page.
// Will limit 15 posts per page, and will order them by the date and time posted (latest posts first)
$get_all_posts_q = mysqli_query ($connect, "SELECT * FROM user_thoughts ORDER BY id DESC ");
$check_rows = mysqli_num_rows($get_all_posts_q);
while ($get_row = mysqli_fetch_array($get_all_posts_q)){
$message = $get_row['message'];
/**** Between the while loop is where I echo the div(s)
which display the above details. *******/
}
当前行为：
目前，通过上面的代码，它显示了所有的用户想法
，即表中有三行，每一行都在显示中，但是，其中的详细信息并不基于这些帖子的作者。例如，编写作者的用户的个人资料图片不显示 这链接了用户和用户的想法。记得清理你的输入
$get_thoughts_from_db = mysqli_query($connect, "SELECT * FROM user_thoughts INNER JOIN users ON user_thoughts.added_by = users.username ON ORDER BY id DESC"); // newest posts first
$query=您易受攻击。请注意，您在循环中获取用户的想法结果，但在循环完成之前，您不会使用这些结果，因此您只能使用上次获取的想法。您是否试图显示单个用户的想法列表，或者所有用户的想法列表？@OscarJ-用户想法表中的每一行都应显示在主页上。所以，为了回答您的问题，所有的用户。@MarcB-您是对的，但是使用问题中描述的while循环，所有的想法都被描述了？我之前确实遇到过一个问题，其中一个“想法”显示了三次（因为user_Thinks表中有三行），但是通过while循环，所有帖子现在都显示出来了。您真正应该做的是使用一个JOIN
ed查询。每当您有嵌套查询，并且内部查询依赖于外部查询的数据时，它们可能/应该被重写为单个联接。