php - 无论 codeigniter 中的排序如何，我都希望在顶部有一组特定的记录

Question

以下函数以二维数组格式返回所有玩家。下面是函数:-

public function get_football_players($type = FOOTBALL_TEXT, $filter = '', $start = '', $limit = '', $player = '') {
        $this->db->select('tblmarkets_football.*, tblmarkets.symbol, tblmarkets.type');
        $this->db->from('tblmarkets_football');
        $this->db->join('tblmarkets','tblmarkets.id = tblmarkets_football.market_id','left');
        if($type != ''){
            $this->db->where('type', $type);
        }
        $this->db->where('active', 1);
        switch ($filter) {
            case 'forward':
                $this->db->where('position', 'Forward');
                break;
            case 'midfielders':
                $this->db->where('position', 'Midfielder');
                break;
            case 'defenders':
                $this->db->where('position', 'Defender');
                break;
            case 'goalkeepers':
                $this->db->where('position', 'Goalkeeper');
                break;
            case 'highest_price':
            case 'lowest_price':
                $tmp = $this->external_api_model->get_filtered_football_pairs($limit, $start, $filter);
                $players = json_decode($tmp, true);
                $this->db->where_in('symbol', $players);
                break;
        }
        if($player != ''){
            $this->db->like('tblmarkets_football.name', $player);
        }
        if($filter != 'highest_price' && $filter != 'lowest_price'){
            $this->db->limit($limit, $start);
         }
        $result = $this->db->get()->result();
        return $result;
    }

当有人应用最高价格过滤器时，get_filtered_football_pairs API 会以数组格式返回所有球员。我希望所有这些玩家都按照我收到的顺序显示在顶部。 $players 包含所有玩家的名字。目前它们是随机显示的。

任何帮助将不胜感激。提前致谢。

编辑

$players 将如下所示:-

Array
(
    [0] => paul-pogba
    [1] => neymar
    [2] => kylian-mbappé
    [3] => lionel-messi
    [4] => jadon-sancho
    [5] => eden-hazard
    [6] => marcus-rashford
    [7] => mohamed-salah
    [8] => harry-kane
    [9] => vinicius-junior
    [10] => callum-hudson-odoi
    [11] => raheem-sterling
    [12] => ousmane-dembele
    [13] => anthony-martial
    [14] => paulo-dybala
    [15] => gareth-bale
    [16] => joshua-kimmich
    [17] => cristiano-ronaldo
    [18] => kai-havertz
    [19] => leroy-sané
)

我想要的顺序是首先显示 paul-pogba，然后是 neymar 等等。

Answer 1

这是未经测试的，但逻辑是您转义 $player 数组中的元素，然后将优先处理应用于符合条件的 symbol 值，然后提供次要排序顺序为 symbol 升序(否则在将玩家与非玩家分开后让事情随机。

case 'highest_price':
case 'lowest_price':
    $tmp = $this->external_api_model->get_filtered_football_pairs($limit, $start, $filter);
    $players = json_decode($tmp, true);
    $this->db->where_in('symbol', $players);
    foreach ($players as &$p) {
        $p = "'" . $this->db->escape_str($p) . "'";
    }
    $this->db->order_by("IF(FIELD(symbol," . implode(",", $players) . ")=0,1,0),
                         FIELD(symbol," . implode(",", $players) . ")");
    break;

这是一个 db-fiddle 演示，展示了如何执行排序:https://www.db-fiddle.com/f/9yxTo3nEHCu9vLPW6MELy3/1

帮助理解我的技术:https://dba.stackexchange.com/a/109126/157408

解释子句的0,1部分...

它将$players 分隔在非$players 之前。所有 $players 都将在 0 组中，非 $players 将在 1 中团体。然后二次排序会将 $players 置于您的首选顺序(打破 0 并列)。

---

附注我认为将 $start 和 $limit 的默认值设置为空字符串是不明智的——数字值似乎更适合。

我通常尽量远离开关 block ，因为我觉得它太冗长了。另一种样式可能如下所示(根据您的预期输入和逻辑要求，您可以进一步简化它):

if (in_array($filter, ['forward', 'midfielders', 'defenders', 'goalkeepers'])) {
    $this->db->where('position', ucfirst(rtrim($filter, 's')));
}

if (in_array($filter, ['highest_price', 'lowest_price'])) {
    $tmp = $this->external_api_model->get_filtered_football_pairs($limit, $start, $filter);
    $players = json_decode($tmp, true);
    $this->db->where_in('symbol', $players);
    foreach ($players as &$p) {
        $p = "'" . $this->db->escape_str($p) . "'";
    }
    $this->db->order_by("IF(FIELD(symbol," . implode(",", $players) . ")=0,1,0),
                         FIELD(symbol," . implode(",", $players) . ")");
} else {
    $this->db->limit($limit, $start);
}

if ($player != '') {
    $this->db->like('tblmarkets_football.name', $player);
}