How to get only date from created_at (datetime)

Try using the DATE() function to extract the date from datetime. If you are using MySQL.

$orders = DB::select('SELECT DATE(created_at) as stat_day, SUM(billing_totalprice) from Orders GROUP BY DATE(created_at) ORDER BY stat_day;');

This is same method as mine. ´´´ $orders = DB::select('SELECT DATE(created_at) as stat_day, SUM(billing_totalprice) from Orders GROUP BY DATE(created_at) ORDER BY stat_day;');

Yes, I use mysql. The problem is that, I am using raw expression, so I can't enter a $variable. I must do some sql function.

why struggle with raw queries?

Don't ask me :) I've been struggling with this for a month. In the end, I decided to write a raw sql.

Ok, this is what i want. Thank you KALEMDZIEVSKI :)

The shorter method could be this for Laravel 8+:

$orders = Order::groupByRaw('DATE(created_at) AS stat_day')
       ->selectRaw('DATE(created_at) AS stat_day, SUM(billing_totalprice) AS total_price')
       ->get()