Question

我有玩家的分数被添加到表格中，我想在PHP中检查他们的分数是否在前10名之内或者在前10名之外。

我有以下内容，现在需要添加查询以对highscore中的DESC进行排序，并让我知道userid是否排在前10位。

电流：

    $currentuser = $_SESSION['userid'];
    $mysqli = new mysqli($hostname, $db_username, $db_password,$db_name);
    if ($mysqli->connect_error) {
        die('Error : ('. $mysqli->connect_errno .') '. $mysqli->connect_error);
    }   

    $res = $mysqli->query("SELECT * FROM players WHERE userid=" . $currentuser);

尝试：

    $currentuser = $_SESSION['userid'];
    $mysqli = new mysqli($hostname, $db_username, $db_password,$db_name);
    if ($mysqli->connect_error) {
        die('Error : ('. $mysqli->connect_errno .') '. $mysqli->connect_error);
    }   

    $current = $mysqli->query("SELECT * FROM players WHERE userid=" . $currentuser);
    $res = $mysqli->query("SELECT * FROM players ORDER BY highscore DESC LIMIT 10");

    foreach ($res as $player) {
       if ($player = $current) {
         echo "in the top 10" }
       else {
         echo "not in the top 10"} 
    }

这是正确的，检查$currentuser是否在前10名中是否正确，或者是否能以更清洁的方式实现？

Answer 1

假设您要列出所有用户，然后表示哪些用户位于前10名，那么这里有一个选项可以将整个列表组合成一个查询，使用子查询获得前10名玩家，{{{ 1}}语句和case：

outer join

SQL Fiddle Demo

鉴于您的意见，这可能是最简单的选择：

select p.userid, 
  case 
    when p2.userid is not null 
    then 'in the top 10'
    else 'not in the top 10'
  end intopten
from players p
  left join (select *
        from players
        order by highscore desc
        limit 10) p2 on p.userid = p2.userid

More Fiddle

Answer 2

您可以使用以下查询：

 $query="SELECT 1 from players WHERE  $currentuser in (SELECT userid FROM players ORDER BY highscore DESC LIMIT 10) LIMIT 1"
if($result=$mysqli->query($query))
{
if($result->num_rows >0 )echo 'in top 10';
else echo 'not in top 10';
}
else echo 'error';

如何检查玩家是否排在前10位（排名）

2 个答案: