多次切片采集

Question

我有一个包含一堆数据的集合。

我正在尝试执行以下操作

• 获取前18个结果并吐出

• 使用循环获取特定位置的前 3 个结果并吐出每个结果

这是我正在尝试做的示例代码：

$data = DataChampion::query()

    ->selectRaw('

        static_champions.name as champion_name, static_champions.slug as champion_slug, static_champions.image as champion_image,

        static_lanes.slug as lane_slug, static_tiers.slug as tier_slug, static_patches.slug as patch_slug,

        ((sum(data_champions.wins) / sum(data_champions.matches)) * 100) as win_rate

    ')

    ->leftJoin('static_champions', 'static_champions.id', 'data_champions.static_champion_id')

    ->leftJoin('static_lanes', 'static_lanes.id', 'data_champions.static_lane_id')

    ->leftJoin('static_tiers', 'static_tiers.id', 'data_champions.static_tier_id')

    ->leftJoin('static_patches', 'static_patches.id', 'data_champions.static_patch_id')

    ->where('data_champions.static_patch_id', StaticPatch::orderByDesc('id')->first()->id)

    ->groupBy('data_champions.static_champion_id')

    ->orderByDesc('win_rate')

    ->get();

foreach ($data->splice(0, 18) as $data) {

    echo $data->champion_name . '<br>';

}

foreach (['top', 'middle', 'bottom'] as $lane_slug) {

    foreach ($data->where('lane_slug', $lane_slug)->splice(0, 3) as $data) {

        echo $lane_slug . ' - ' . $data->champion_name . '<br>';

    }

}

我不断收到错误：

调用未定义的方法 Illuminate\Database\Eloquent\Builder::splice()

当我删除foreach (['top', 'middle'...整个循环时，它似乎适用于前 18 个结果。

如何从单个集合中获取我想要的数据，这样我就不必对相同的数据使用多个查询？

Answer 1

更改如下几行 - 在迭代集合（即 $data）时不能使用相同的变量名。foreach ($data->splice(0, 18) as $val) {&nbsp; &nbsp; echo $val->champion_name . '<br>';}foreach (['top', 'middle', 'bottom'] as $lane_slug) {&nbsp; &nbsp; foreach ($data->where('lane_slug', $lane_slug)->splice(0, 3) as $val) {&nbsp; &nbsp; &nbsp; &nbsp; echo $lane_slug . ' - ' . $val->champion_name . '<br>';&nbsp; &nbsp; }}

Answer 2

也许是因为你在那个 foreach 中添加了一个 where，集合变成了一个查询构建器，尝试在那个之后添加一个 ->get()