通过与不同服务器的多个数据库连接访问多对多关系数据 [英] Access relational data of many to many relationship with multiple database connection with different server

问题描述

我正在使用不同服务器上的多个数据库连接.即host1和host2.我的默认数据库连接为host2.我的项目有两个表. users在主机1上存在，而 tasks在主机2上存在.

I'm working with multiple database connection on different servers. i.e, host1 and host2. My default database connection is host2. My project have two tables. users exists on host1 and tasks exists on host2.

两个表上都有一个many to many关系.与此关系的数据透视表是 task_users，该数据存在于host2 .

There is a many to many relationship on both tables. Pivot table for this relationship is task_users which exists on host2.

我的模型文件在这里.

User.php

class User extends Authenticatable
{

    protected $connection = 'host1';

    public function tasks()
    {
        return $this->belongsToMany(Task::class, 'task_users', 'user_id', 'task_id');
    }
}

Task.php

class Task extends Model
{
    protected $connection = 'host2';

    public function users()
    {
        return $this->belongsToMany(User::class, 'task_users', 'task_id', 'user_id');
    }
}

使用此模型文件时，当我试图吸引任务的用户时，会出现此错误.

With this model files, when I'm trying to get users of a task, I'm getting this error.

找不到基本表或视图:1146表'database_hosted_on_host1_server.task_users'不存在.

Base table or view not found: 1146 Table 'database_hosted_on_host1_server.task_users' doesn't exist.

这是我的控制器代码

$task = Task::find($taskId);
dd($task->users->toArray());

我也尝试过此也.但是只有两个数据库都在同一服务器上时，它才起作用.

I have also tried this too. But it works only if both database are on same server.

我还尝试了定义

I have also tried Defining Custom Intermediate Table Models from laravel documentation. But still getting error. I think I'm doing some mistake in pivot class.

这是我的代码.

Task.php

class Task extend Model
{
    protected $connection = 'host2';

    public function users()
    {
        return $this->belongsToMany(User::class)->using(TaskUser::class);
    }
}

TaskUser.php

使用Illuminate \ Database \ Eloquent \ Relations \ Pivot;

use Illuminate\Database\Eloquent\Relations\Pivot;

class TaskUser extends Pivot
{
    protected $connection = 'host2';
    protected $table = 'task_users';
}

使用此代码，当我试图吸引任务的用户时，我遇到了此错误.

With this code, when I'm trying to get users of a task, I'm getting this error.

找不到基本表或视图:1146表'database_hosted_on_host1_server.task_user'不存在.

Base table or view not found: 1146 Table 'database_hosted_on_host1_server.task_user' doesn't exist.

在两个代码中，关系表都被分配了host1连接(相关表即用户的连接).但是它存在于host2连接中.而且我的默认连接是host2.

In both code, relational table is getting assigned with host1 connection (connection of related table i.e, users). But it exists in host2 connection. And also my default connection is host2.

我几乎花了太多时间来解决这个问题.但是没有任何办法.如果有人知道答案，将不胜感激.

I have almost spent too much time to resolve this. But didn't get any way. If anyone knows the answer, it will be appreciated.

推荐答案

好的.我从github上的 themsaid 得到了答案.他说，不同连接上的多对多关系只能在一个方向上起作用，而在另一个方向上却不起作用.在这里您可以找到 github问题.

Okay. I got the answer from themsaid on github. He said that many to many relationships on different connections would work in 1 direction only but not the other. Here you can find github issue.

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