Laravel：调用一个成员函数where（）on float

Question

I was trying to find sum of different column using Query Builder. Here is Query :

   DB::table('carts')                
           ->sum(\DB::raw('carts.price+COALESCE(carts.support,0)+COALESCE(carts.installation,0)' ))
           ->where('status','=',1)  
           ->where('user_id','=',$id);

But when i dd() the output i got the above Error.ie,

Call to a member function where() on float

How do i avoid that?

Answer 1

You should call sum at the end of the query:

DB::table('carts')
   ->where('status', 1)  
   ->where('user_id', $id)
   ->sum(\DB::raw(
       'carts.price 
       + COALESCE(carts.support, 0) 
       + COALESCE(carts.installation, 0)' 
   ));