CakePHP sum a column then group by month.

I have below sql query to get summation of a column name amount , where the result will be grouped by month.

SELECT 
  MONTHNAME( created ) as monthname,
  sum( amount ) as total
FROM 
  transactions
GROUP BY
  monthname

Example, In transactions table I have an amount field where the amount is a numeric value field and transactions have created and modified fields.

So, we can write this query in query builder like below way

public function index()
{
    $query = $this->Transactions->find();
    $query->select([
        ‘monthname’ => $query->func()->monthname([
            ‘created’ => ‘identifier’
         ]),
         ‘total’ => $query->func()->sum(‘Transactions.amount’)
    ])
    ->group([‘month’]);
}

After iteration we should get the result like below

monthname  total
July                    100
May                  300
….. …..