Laravel Eloquent
->whereHas()
使用 exists()
子查询 - https://dev.mysql.com/doc/refman/8.0/en/exists-and-not-exists-subqueries.html - 为了返回您的结果。
我想编写自己的子查询,但我不知道如何告诉 Eloquent -> 它在哪里。
如果我这样做:
$query->where( DB::raw(' exists( subquery ) ')
Laravel 将子查询写为:
where exists( subquery ) is null
所以我只是想知道什么
$query->method()
可以用来向'where'语句添加一个exists()子查询。子查询与 laravel 生成的类型相同,但写出来了:
... and exists ( select * from `tbl` inner join `assets` on `custom_assets`.`id` = `tbl`.`asset_id` where `assets`.`deleted_at` is null and `users`.`id` = `assets`.`client_id` and `field_id` = ? and (`value` = ? and `assets`.`deleted_at` is null )
您可以在那里找到此代码示例。您还可以在 whereHas 中为自定义查询添加闭包。
// Retrieve all posts with at least one comment containing words like foo%
$posts = App\Post::whereHas('comments', function ($query) {
$query->where('content', 'like', 'foo%');
})->get();
请在文档中寻找答案: https://laravel.com/docs/11.x/queries#where-exists-clauses
$users = DB::table('users')
->whereExists(function (Builder $query) {
$query->select(DB::raw(1))
->from('orders')
->whereColumn('orders.user_id', 'users.id');
})
->get();