Laravel 分页不适用于 group by 子句

Question

Laravel 分页似乎无法与 group by 子句一起正常工作。例如:

$users = Subject::select(DB::raw('subjects.*, count(user_subjects.id) as total_users'))
            ->join('user_subjects', 'user_subjects.subject_id', '=', 'subjects.id')
            ->whereNull('user_subjects.deleted_at')
            ->groupBy('subjects.id')
            ->orderBy('subjects.updated_at', 'desc')
            ->paginate(25);

已制作

select subjects.*, count(user_subjects.id) as total_users 
from `subjects` inner join `user_subjects` on `user_subjects`.`subject_id` = `subjects`.`id` 
where `subjects`.`deleted_at` is null and `user_subjects`.`deleted_at` is null 
group by `subjects`.`id` 
order by `subjects`.`updated_at` desc

请注意，查询中没有 limit 子句。

如果查询中没有 group by 子句，则工作正常:

$users = Subject::select(DB::raw('subjects.*, count(user_subjects.id) as total_users'))
            ->join('user_subjects', 'user_subjects.subject_id', '=', 'subjects.id')
            ->whereNull('user_subjects.deleted_at')
            ->orderBy('subjects.updated_at', 'desc')
            ->paginate(25);

生成以下查询:

select subjects.*, count(user_subjects.id) as total_users from `subjects` 
inner join `user_subjects` on `user_subjects`.`subject_id` = `subjects`.`id`
where `subjects`.`deleted_at` is null and `user_subjects`.`deleted_at` is null 
order by `subjects`.`updated_at` desc 
limit 25 offset 0

有人知道我该如何解决这个问题吗？

Answer 1

检查文档 https://laravel.com/docs/5.2/pagination

Currently, pagination operations that use a groupBy statement cannot be executed efficiently by Laravel. If you need to use a groupBy with a paginated result set, it is recommended that you query the database and create a paginator manually.