Php Mysql 只回显一半结果，有时甚至没有

Question

我正在尝试回显用户名。我有一个表，其中只有 USERID ，然后我获取该 USEDID 并将其与另一个表进行比较，并从那里回显 USERNAME 。但是如果有 50 个条目，那么它只会回显 25 。

这是代码

<?php while($row = mysqli_fetch_assoc($result)) {
$user_id = $row['user_id'];
$result2 = mysqli_query($conn, "select * from `users` WHERE `user_id` = '$user_id'");
$row2 = mysqli_fetch_assoc($result2);
while($row2 = mysqli_fetch_assoc($result2)){
$username = $row2['username'];
}
 ?>
<tr>
<td><?php echo $row['id']; ?></td>
<td><?php echo $row['user_id']; ?></td>
<td><?php echo $username; ?></td>
<td><?php echo $row['points']; ?></td>
</tr>

This above code doesnt echo anything at all in username but echo all results

如果我改变

$row2 = mysqli_fetch_assoc($result2);

至

$row2 = mysqli_fetch_assoc($result);

It echo everything with username but only few/half results

与此相关的其他代码

$result = mysqli_query($conn, "select * from `lottery`");
    $row = mysqli_fetch_assoc($result); 

Answer 1

删除此行:

$row2 = mysqli_fetch_assoc($result2)