Laravel Eloquent LEFT JOIN WHERE NULL

php mysql laravel eloquent laravel-4

2022-08-30 11:19:52

我正在尝试使用 Eloquent 在数据库种子期间执行以下查询：

SELECT
    *
FROM
    customers
LEFT JOIN
    orders
    ON customers.id = orders.customer_id
WHERE
    orders.customer_id IS NULL

这是我在Eloquent中的实现：

$c = Customer::leftJoin('orders', function($join) {
      $join->on('customers.id', '=', 'orders.customer_id');
    })
    ->whereNull('orders.customer_id')
    ->first();

第一个查询始终返回完整结果，而 Eloquent 等效项始终为除表的和字段之外的所有内容返回空元素。我不知所措，因为和模型都是工匠生成的骨架。emailphonecustomersCustomersOrders

前任：

class Customer extends \Eloquent {

    // Add your validation rules here
    public static $rules = [
        // 'title' => 'required'
    ];

    // Don't forget to fill this array
    protected $fillable = [];

}

下面是当我 dd（）对种子（最初由 Faker 生成）的第一个 Eloquent 查询时输出的数组：

protected $original =>
  array(25) {
    'id' =>
    NULL
    'first_name' =>
    NULL
    'last_name' =>
    NULL
    'email' =>
    string(24) "luther.braun@example.org"
    'phone' =>
    string(17) "642.150.9176x5684"
    'address1' =>
    NULL
    'address2' =>
    NULL
    'city' =>
    NULL
    'state' =>
    NULL
    'county' =>
    NULL
    'district' =>
    NULL
    'postal_code' =>
    NULL
    'country' =>
    NULL
    'notes' =>
    NULL
    'created_at' =>
    NULL
    'updated_at' =>
    NULL
    'customer_id' =>
    NULL
    'total' =>
    NULL
}

答案 1

这可以通过指定特定表中所需的特定列名称来解决，如下所示：

$c = Customer::leftJoin('orders', function($join) {
      $join->on('customers.id', '=', 'orders.customer_id');
    })
    ->whereNull('orders.customer_id')
    ->first([
        'customers.id',
        'customers.first_name',
        'customers.last_name',
        'customers.email',
        'customers.phone',
        'customers.address1',
        'customers.address2',
        'customers.city',
        'customers.state',
        'customers.county',
        'customers.district',
        'customers.postal_code',
        'customers.country'
    ]);

答案 2

您还可以在选择中指定列，如下所示：

$c = Customer::select('*', DB::raw('customers.id AS id, customers.first_name AS first_name, customers.last_name AS last_name'))
->leftJoin('orders', function($join) {
  $join->on('customers.id', '=', 'orders.customer_id') 
})->whereNull('orders.customer_id')->first();