Laravel Eloquent:关系的多个外键 [英] Laravel Eloquent: multiple foreign keys for relationship

问题描述

我正在将一个项目移植到 Laravel.

I am in the process of porting a project to Laravel.

我有两个数据库表，它们之间是一对多的关系.它们由三个条件连接.我如何在 Eloquent 中为这种关系建模?

I have two database tables which are in a One-To-Many relationship with each other. They are joined by three conditions. How do I model this relationship in Eloquent?

我不应该修改数据库架构，因为它必须与其他东西保持向后兼容.

I am not supposed to modify the database schema, since it has to remain backwards compatible with other things.

我尝试了以下方法，但不起作用.

I have tried the following, but it doesn't work.

拥有方:

use IlluminateDatabaseEloquentModel;

class Route extends Model
{
    public function trips()
    {
        return $this->hasMany('Trip', 'route_name,source_file', 'route_name,source_file')
    }
}

反面:

use IlluminateDatabaseEloquentModel;

class Trip extends Model
{
    public function routes()
    {
        return $this->belongsTo('Route', 'route_name,source_file', 'route_name,source_file');
    }
}

示例 Route 数据库值:

id    | route_name     | source_file
---------------------------------------
1     | Berlin - Paris | file1.xls   
2     | Madrid - London| file2.xls
3     | Berlin - Paris | file3.xls

示例 Trip 数据库值:

id        | route_name           | source_file | duration
---------------------------------------------------------
1         | Berlin - Paris       | file1.xls   | 78
2         | Madrid - London      | file2.xls   | 241
3         | Berlin - Paris       | file3.xls   | 65
1         | Berlin - Paris       | file1.xls   | 95
1         | Berlin - Paris       | file1.xls   | 65

Route 和 Trip 有其他属性，为简洁起见我没有在这里包括.

Route and Trip have other attributes, which I did not include here for brevity.

这在 Eloquent 中可行吗?

Is this possible in Eloquent?

推荐答案

我不得不处理类似的问题.@fab 提供的解决方案不适用于预加载，因为在处理关系时 $this->source_file 将为 null.我想出了这个解决方案

I had to deal with a similar problem. The solution provided by @fab won't work with eager loading because $this->source_file would be null at the time the relationship is processed. I came up with this solution

安装 Compoships 并在您的模型中对其进行配置后，您可以定义与多个列匹配的关系.

After installing Compoships and configuring it in your models, you can define your relationships matching multiple columns.

拥有方:

use IlluminateDatabaseEloquentModel;
use AwobazComposhipsCompoships;

class Route extends Model
{
    use Compoships;

    public function trips()
    {
        return $this->hasMany('Trip', ['id', 'route_name', 'source_file'], ['route_id', 'route_name', 'source_file']);
    }
}

反面:

use IlluminateDatabaseEloquentModel;
use AwobazComposhipsCompoships;

class Trip extends Model
{
    use Compoships;

    public function route()
    {
        return $this->belongsTo('Route', ['route_id', 'route_name', 'source_file'], ['id', 'route_name', 'source_file']);
    }
}

Compoships 支持预先加载.

Compoships supports eager loading.

这篇关于Laravel Eloquent:关系的多个外键的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！