Laravel中的反向关系查找

Question

如何在Eloquent中执行以下查询？

SELECT count(*) as total, age
FROM user
JOIN role ON user.role_id = role.id
WHERE role.name = 'maintenance'
GROUP BY age

（其中＆＃39;年龄＆＃39;是用户）

Answer 1

未测试：

$total = App\User::whereHas('roles', function ($query) {
    $query->where('name', 'maintenance');
})->groupBy('age')->count();