sql select sum group by id laravel
Document::groupBy('users_editor_id')
->selectRaw('sum(no_of_pages) as sum, users_editor_id')
->pluck('sum','users_editor_id');
// originally lists(), which was deprecated in favour of pluck in 5.2
// and dropped completely in 5.3
// ->lists('sum','users_editor_id');
// returns array like this:
array(
users_editor_id => sum,
...
)