php - 如何从 laravel mongodb 的结果集中删除主键？

Question

我有以下查询

$tag_query = UserTags::query();
$tag_query->whereIn('tag_id' , $insert_data['to_device']);
$tag_users = $tag_query->get(['user_id']);

它正在生成以下结果 -

Array
(
    [0] => Array
        (
            [_id] => 57da358e7ac6f6740e8b456a
            [user_id] => 57d67290823fb647dd174739
        )

    [1] => Array
        (
            [_id] => 57da358e7ac6f6740e8b456c
            [user_id] => 57d672cb823fb647dd17473a
        )

    [2] => Array
        (
            [_id] => 57da358e7ac6f6740e8b4571
            [user_id] => 57d67549d81e1845e4dba983
        )
)

我不想在结果数组中使用 _id，如何在不使用循环的情况下删除它？预期输出 -

Array
(
    [0] => Array
        (
            [user_id] => 57d67290823fb647dd174739
        )

    [1] => Array
        (
            [user_id] => 57d672cb823fb647dd17473a
        )

    [2] => Array
        (
            [user_id] => 57d67549d81e1845e4dba983
        )
)

请帮忙!谢谢!

Answer 1

您可以使用 project() 方法将投影应用于您的查询:

$tag_query = UserTags::query();
$tag_query->whereIn('tag_id' , $insert_data['to_device']);
$tag_users = $tag_query->project(['_id' => 0, 'user_id' => 1])->get();