根据城市和支付类型总结和分组与laravel雄辩

Question

我有三个不同的表：城市，payment_types和付款。我想为付款创建摘要报告。

城市表：

然后付款类型表：

付款表：

我想得到的是（我想创建此摘要）

所以，根据汇总城市不重复并按payment_types分组。

如何使用Eloquent创建此查询？

Answer 1

首先，您需要为您的雄辩模型创建适当的关系，例如：

City.php

class City extends Model {

    public function payments() {
        return $this->hasMany('App\Payment');
    }

}

PaymentType.php

class PaymentType extends Model {

    public function payments() {
        return $this->hasMany('App\Payment');
    }

}

Payment.php

class Payment extends Model {

    public function city() {
        return $this->belongsTo('App\City');
    }

    public function payment_type() {
        return $this->belongsTo('App\PaymentType');
    }

    public function scopeFromCity($query, $cityId) {
        return $query->where('city_id', $cityId);
    }

}

完成初始设置后，您就可以开始创建报告了：

// Get all cities from DB
$cities = \App\City::all();

// Loop through each city
$cities->each(function($city) {
    // Print city id and name
    echo "City ID {$city->id}\n";
    echo "City Name {$city->name}\n";

    // Now we will fetch all unique payment types for this city
    // and we will loop through each of them
    // calculating the total of payments done
    // for this payment type and city_id
    $paymentTypes = \App\PaymentType::whereIn('id', \App\Payment::where('city_id', $city->id)->lists('payment_type_id'));
    $paymentTypes->distinct()->get()->each(
        function($paymentType) use ($city) {
            echo "Payment type {$paymentType->type}\n";
            $total = $paymentType->payments()->fromCity($city->id)->sum('payment');
            echo "Total {$total}\n";
    });
});

您可以从documentation找到有关Eloquent的更多信息，Taylor已经通过示例很好地解释了所有内容。