Laravel 对某一列进行筛选然后求和sum()的例子

StudentLessonProgress::where('student_info_id', $student_info_id)   ->sum('total_left_class_num');

array:1 [ 0 => array:3 [ “query” => “select sum(total_left_class_num) as aggregate from student_lesson_progress where student_info_id = ?” “bindings” => array:1 [▶] “time” => 51.48 ] ]

Product::where('status',1)->first( array(  /DB::raw('SUM(profit) as profit'),  /DB::raw('SUM(order_count) as order_count') ))->toArray();