getting specific column values laravel code example

Example 1: laravel get single column value

$items = DB::table('items')
             ->select('id', 'ref_code', 'name', 'price')
             ->where('ref_code','=', $request->ref_code)
             ->first();

Example 2: get specific columns using with() function in laravel eloquent

Post::with('user:id,username')->get();