Question

我使用以下查询生成器：

$res = Announcement::whereExists(function ($query) {
                $query->select(DB::raw(1))
                    ->from('announcement_category')
                    ->join('user_category', 'user_category.category_id', '=', 'announcement_category.category_id')
                    ->where('user_category.user_id', 1)
                    ->where('announcement_category.announcement_id', '=', 'announcements.id')
                    ->whereNull('deleted_at');
            })->get();

如何使用短格式with重写此查询：

Announcement::with("announcement_category")...

因为在这个查询中，构建器最后添加了条件和where delete_at NOT null，并且它的工作错误。

表之间的关系：

Announcement           Announcement_category          User_category
_____________          ____________________________   _______________
id | name             announcement_id | category_id   user_id | category_id

1）Announcement可以有一个或多个类别(Announcement has many Announcement_category)

2）用户可以有一个或多个类别

3）User_category与Announcement_category

的category_id = category_id相关

Answer 1

您应首先定义Announcement和AnnouncementCategory之间的关系

public function announcement_category() {
 return $this->hasMany(AnnouncementCategory::class, 'announcement_id')
}

然后，在你去的时候为关系添加条件，甚至在关系函数中设置它。

如何在Laravel中重写SQL查询？

1 个答案: