Laravel Sum of relation

问题

I want to return the sum of "amount" from my payments table. There can be many payments for one invoice. The below "->sum('amount') does not work, it returns:

Call to a member function addEagerConstraints() on a non-object.

How to return the sum of all payments for each invoice in my relation?

Invoices Model:

class Invoices extends Eloquent {

    public function payments()
    {
        return $this->hasMany('Payments')->sum('amount');
    }
}

Expenses Model:

class Payments extends Eloquent {

    public function invoices()
    {
        return $this->belongsTo('Invoices');
    } 
}

My table "payments" holds the foreign key of my tables invoices, which is invoices_id.

回答1:

class Invoices extends Eloquent {

    public function payments()
    {
        return $this->hasMany('Payments');
    }
}

class Payments extends Eloquent {

    public function invoices()
    {
        return $this->belongsTo('Invoices');
    } 
}

In your controller

Invoice::with(['payments' => function($query){
   $query->sum('amount');
}])->get();

;

回答2:

First decide which Invoice (for example id 1)

$invoice = Invoices::find(1);

Then eager load all the corresponding payments

$eagerload = $invoice->payments;

Finally assuming you have the amount field in your Invoice model you can simply find the sum using the method below:

$totalsum = $eagerload->sum('amount');

回答3:

This is also possible. we can do by model itself.

class Invoices extends Eloquent {

    public function payments()
    {
        return $this->hasMany('Payments')
            ->selectRaw('SUM(payments.amount) as payment_amount')
            ->groupBy('id'); // as per our requirements.
        }
    }
}

Note SUM(payments.amount)

payments is tableName

amount is fieldName

回答4:

I found a simple way to acomplish this in here, you can use withPivot() method.

You can redefine a bit your relation to something like following

public function expenses()
{
    return $this->belongsToMany('Expenses', 'invoices_expenses')
                   ->withPivot('name', 'amount', 'date');
}

回答5:

You can show this package

$invoices = Invoices::withSum('payments:amount')->get();

来源：https://stackoverflow.com/questions/31853838/laravel-sum-of-relation

标签

laravel

laravel-4

sum

relation