php Eloquent - 调用未定义的关系
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Eloquent - Call to undefined relationship
提问by Kieran Chadwick
I have a userstable and a permissionstable. It's a many-to-many relationship so I also have a users_permissionstable with a user_id& module_permission_idcolumn.
我有一个用户表和一个权限表。这是一个多对多的关系，所以我还有一个带有user_id和module_permission_id列的users_permissions表。
The user model has the following relationship:
用户模型有如下关系：
public function permissions()
{
return $this->belongsToMany(Permission::class, 'users_permissions', 'user_id', 'module_permission_id');
}
When I run my query, the result contains an empty permissions array.
当我运行查询时，结果包含一个空的权限数组。
User::with('permissions');
If I echo the query in the with, I get the error: Call to undefined relationship [] on model [App\Models\User]
如果我在 with 中回显查询，则会收到错误消息：调用模型 [App\Models\User] 上的未定义关系 []
User::with(['permissions', function($q) {
echo $q->toSql();
die();
}]);
The rest of the query works, it's just trying to get permissions which is failing.
查询的其余部分有效，它只是尝试获取失败的权限。
回答by vincentLg
Maybe you just forgot the ->get() after User::with('permissions')->get() ?
也许你只是忘记了 User::with('permissions')->get() 之后的 ->get() ？
回答by PHZ.fi-Pharazon
In my case it was a coding convention issue related to camelCase vs. snake_case: In the Model there was
在我的情况下，这是一个与camelCase vs. snake_case相关的编码约定问题：在模型中有
public function getPermissions()
and in the query there was
在查询中有
User::with(['get_permissions'])
When I changed this to
当我把它改成
User::with(['getPermissions'])
it started to work, although I'd say the Laravel way would be to use snake_case instead.
它开始工作了，虽然我会说 Laravel 的方式是使用 snake_case 代替。
This confused me for a couple of days since frameworks like Symfony and AngularJs has a mixed conventions that somewhere you need to write parameters in snake_case and somewhere else in camelCase. I didn't find any documentation on Laravel site how they handle this, so I tried it the Straight Way and it seemed to be the case here :)
这让我困惑了几天，因为像 Symfony 和 AngularJs 这样的框架有一个混合的约定，你需要在蛇的某处写参数，而在 camelCase 的其他地方。我没有在 Laravel 网站上找到任何他们如何处理这个问题的文档，所以我尝试了直接方式，这里似乎就是这种情况:)
