问：如何编写代码，以便php强制mysql只显示该列的最后一行？
以下是我如何编码（2个复制的YouTube tut）以显示所有行以允许用户删除多行的方法：示例1
[php]
<?php
session_start();
require "conn.php";
require "site_details.php"; ?>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<title>Follow Users</title>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
</head>
<body>
<form name="form" action="" method="post">
<table border=1 cellpadding=1 cellspacing=1>
<tr>
<th>Id</th>
<th>Username</th>
<th>Password</th>
<th>Email</th>
<th>Delete</th>
</tr>
<?php
$res=mysqli_query($conn,"SELECT * FROM users");
while($row=mysqli_fetch_array($res))
{
echo "<tr>";
echo "<td>"; ?> <input type="checkbox" name="num[]" class="other" value="<?php echo $row["id"]; ?>" /> <?php echo "</td>";
echo "<td>"; echo $row["ids"]; echo "</td>";
echo "<td>"; echo $row["usernames"]; echo "</td>";
echo "<td>"; echo $row["passwords"]; echo "</td>";
echo "<td>"; echo $row["emails"]; echo "</td>";
echo "</tr>";
}
?>
</table>
<input type="submit" name="submit" value="delete selected">
</form>
<?php
if(isset($_POST["submit"]))
{
$box=$_POST['num'];
while (list ($key,$val) = @each ($box))
{
mysqli_query($conn,"DELETE FROM users WHERE id='$val'");
}
?>
<script type="text/javascript">
window.location.href=window.location.href;
</script>
<?php
}
?>
</body>
</html>
[/php]
范例2：
[php]
<?php
session_start();
require "conn.php";
require "site_details.php"; ?>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<title>Follow Users</title>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
</head>
<body>
<table border=1 cellpadding=1 cellspacing=1>
<tr>
<th>Id</th>
<th>Username</th>
<th>Password</th>
<th>Email</th>
<th>Delete</th>
</tr>
<?php
$sql = "SELECT * FROM users";
$result = mysqli_query($conn,$sql);
while($row = mysqli_fetch_array($result))
{
echo "<tr>";
echo "<td>".$row['ids']."</td>";
echo "<td>".$row['usernames']."</td>";
echo "<td>".$row['passwords']."</td>";
echo "<td>".$row['emails']."</td>";
echo "<td><a href=delete2b.php?id=".$row['ids'].">Delete</a></td>";
}
?>
</table>
</body>
</html>
[/php]
答：将SQL查询从“ SELECT * FROM users”更改为“ SELECT * FROM users ORDER BY id DESC LIMIT 1”
