问题描述
我使用以下查询生成器:
I use the following Query Builder:
$res = Announcement::whereExists(function ($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();
如何使用简短格式with重写此查询:
How to rewrite this query using short form with:
Announcement::with("announcement_category")...
因为，在此查询中，构建器最后添加了conditon和where delete_at NOT null，所以它是错误的.
Because, in this query builders adds conditon and where delete_at NOT null in the end, and it works wrong.
表之间的关系:
Announcement Announcement_category User_category
_____________ ____________________________ _______________
id | name announcement_id | category_id user_id | category_id
1)Announcement可以具有一个或多个类别(Announcement has many Announcement_category)
1) Announcement can has one or more categories (Announcement has many Announcement_category)
2)用户可以具有一个或多个类别
2) User can has one or more categories
3)User_category通过category_id = category_id
推荐答案
您应该先定义Announcement和AnnouncementCategory之间的关系
You should define the relationship between Announcement and AnnouncementCategory first
public function announcement_category() {
return $this->hasMany(AnnouncementCategory::class, 'announcement_id')
}
然后，在关系中添加条件，甚至在关系函数中对其进行设置.
Then, add condition to the relationship as you go or even set it up in the relationship function.
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