Php 如何从不同的表中获取特定用户的数据

我想在用户登录后立即显示数据库A中用户1的数据，此时页面显示表中的所有数据

目前我有两个表，分别用于用户登录和用户事务。因此，在他们登录后，我希望他们能够查看自己的记录。在做了搜索之后，我认为这与会话有关

有人能帮我吗

connection.php

<?php
$mysql_host = "localhost";
$mysql_user = "root";
$mysql_pass = "";
$mysl_database = "mockup";

$conn = mysql_connect($mysql_host, $mysql_user, $mysql_pass);
mysql_select_db($mysl_database, $conn);
?>

<?php
include("connection.php");

if(isset($_POST["submit"])) {
$username = $_POST["username"];
$password = $_POST["password"];

$sql = "SELECT * FROM user
        WHERE username='$username' AND password='$password'";
$result = mysql_query($sql);
$numRows = mysql_num_rows($result);
if($numRows==1) {
    session_start();
    $_SESSION["ID"] = $ID;
    header("Location: ./profile_page.php");
} else {
    echo "Invalid Login Information";   
}
}
?>

<form action="<?php echo $_SERVER['SCRIPT_NAME']; ?>" method="post">
<table>
<tr><td>User Name</td><td><input type="text" name="username" /></td></tr>
<tr><td>Password</td><td><input type="password" name="password" /></td></tr>
<tr><td></td><td><input type="submit" name="submit" value="Login" /></td></tr>
</table>
</form>

<?php
session_start(); // start the session
include("connection.php");

$ID = $_SESSION["ID"]; // store the user id into session

$sql = "SELECT * FROM transaction WHERE ID='$ID'";
$result = mysql_query($sql);

if($row = mysql_fetch_array($result)) {
$deposit = $row["deposit"];


echo "
<table>
    <tr><td>transaction</td><td> : </td><td>$transaction</td></tr>

</table>
";
}
?>

login.php

<?php
$mysql_host = "localhost";
$mysql_user = "root";
$mysql_pass = "";
$mysl_database = "mockup";

$conn = mysql_connect($mysql_host, $mysql_user, $mysql_pass);
mysql_select_db($mysl_database, $conn);
?>

<?php
include("connection.php");

if(isset($_POST["submit"])) {
$username = $_POST["username"];
$password = $_POST["password"];

$sql = "SELECT * FROM user
        WHERE username='$username' AND password='$password'";
$result = mysql_query($sql);
$numRows = mysql_num_rows($result);
if($numRows==1) {
    session_start();
    $_SESSION["ID"] = $ID;
    header("Location: ./profile_page.php");
} else {
    echo "Invalid Login Information";   
}
}
?>

<form action="<?php echo $_SERVER['SCRIPT_NAME']; ?>" method="post">
<table>
<tr><td>User Name</td><td><input type="text" name="username" /></td></tr>
<tr><td>Password</td><td><input type="password" name="password" /></td></tr>
<tr><td></td><td><input type="submit" name="submit" value="Login" /></td></tr>
</table>
</form>

<?php
session_start(); // start the session
include("connection.php");

$ID = $_SESSION["ID"]; // store the user id into session

$sql = "SELECT * FROM transaction WHERE ID='$ID'";
$result = mysql_query($sql);

if($row = mysql_fetch_array($result)) {
$deposit = $row["deposit"];


echo "
<table>
    <tr><td>transaction</td><td> : </td><td>$transaction</td></tr>

</table>
";
}
?>

connection.php

<?php
$mysql_host = "localhost";
$mysql_user = "root";
$mysql_pass = "";
$mysl_database = "database_name";

$conn = mysql_connect($mysql_host, $mysql_user, $mysql_pass);
mysql_select_db($mysl_database, $conn);
?>



login.php

<?php
include("connection.php");

if(isset($_POST["submit"])) {
    $username = $_POST["username"];
    $pass = $_POST["pass"];

    $sql = "SELECT * FROM tbl_user
            WHERE username='$username' AND pass='$pass'";
    $result = mysql_query($sql);
    $numRows = mysql_num_rows($result);
    if($numRows==1) {
        session_start();
        $_SESSION["userid"] = $userid;
        header("Location: ./profile_page.php");
    } else {
        echo "Invalid Login Information";   
    }
}
?>

<form action="<?php echo $_SERVER['SCRIPT_NAME']; ?>" method="post">
<table>
<tr><td>User Name</td><td><input type="text" name="username" /></td></tr>
<tr><td>Password</td><td><input type="password" name="pass" /></td></tr>
<tr><td></td><td><input type="submit" name="submit" value="Login" /></td></tr>
</table>
</form>

在用户成功登录后，您可以借助会话保护和访问用户数据

您可以使用
session\u start（）
启动新会话或恢复现有会话

<?php
session_start();
if(empty($_SESSION['user_sesion_variable']))
  {
    header("location:login.php");
   die();
}
// here go your user database value

您可以在会话中存储用户ID，然后从该用户ID您可以轻松地从数据库中获取登录用户的数据。谢谢，或者您的响应，但是做什么呢？？脚本名称是文件的绝对路径。我知道，我试着在我的数据库中使用您的代码，它会转到profile_page.php，但不会产生任何结果，只是一张空白页。我需要在数据库中的表上设置任何内容吗？必须在connection.php文件中设置数据库名称和其他信息。在profile_page.php中，您必须设置表名，并根据表名设置字段名。是的，我已经这样做了，但我是否需要在列ID中设置主键或其他内容？