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
下面是我在Eloquent中的实现:
$c = Customer::leftJoin('orders', function($join) {
$join->on('customers.id', '=', 'orders.customer_id');
})
->whereNull('orders.customer_id')
->first();
第一个查询总是返回完整的结果,而Eloquent等价查询总是为customers
表的email
和phone
字段以外的所有字段返回空元素。我无法解释这一点,因为Customers
和Orders
模型都是手工生成的骨架。
例如:
class Customer extends 'Eloquent {
// Add your validation rules here
public static $rules = [
// 'title' => 'required'
];
// Don't forget to fill this array
protected $fillable = [];
}
以下是当我对种子(最初由Faker生成)执行第一个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
}
这可以通过从特定表中指定所需的特定列名来解决,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'
]);
虽然其他答案很有效,但我想给你我经常使用的替代短版本:
Customer::select('customers.*')
->leftJoin('orders', 'customers.id', '=', 'orders.customer_id')
->whereNull('orders.customer_id')->first();
和laravel version 5.3
一样,增加了一个功能,这将使您的工作更加简单,例如:
Customer::doesntHave('orders')->get();
您也可以在select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();
我会转储您的查询,这样您就可以查看实际执行的SQL,并了解它与您编写的内容有何不同。
您应该能够用以下代码做到这一点:
$queries = DB::getQueryLog();
$last_query = end($queries);
var_dump($last_query);
die();
希望这能给你足够的信息,让你找出问题所在。
我将使用laravelwhere DoesntHave来实现这一点。
Customer::whereDoesntHave('orders')->get();
use Illuminate'Database'Eloquent'Builder;
$query = Customers::with('orders');
$query = $query->whereHas('orders', function (Builder $query) use ($request) {
$query = $query->where('orders.customer_id', 'NULL')
});
$query = $query->get();