Cross-Database Relationships ​

If you're using a hybrid MongoDB and SQL setup, you can define relationships across them.

The model will automatically return a MongoDB-related or SQL-related relation based on the type of the related model.

If you want this functionality to work both ways, your SQL-models will need to use the Jenssegers\Mongodb\Eloquent\HybridRelations trait.

This functionality only works for hasOne, hasMany and belongsTo.

The MySQL model should use the HybridRelations trait:

use Jenssegers\Mongodb\Eloquent\HybridRelations;

class User extends Model
{
    use HybridRelations;

    protected $connection = 'mysql';

    public function messages()
    {
        return $this->hasMany(Message::class);
    }
}

Within your MongoDB model, you should define the relationship:

use Jenssegers\Mongodb\Eloquent\Model;

class Message extends Model
{
    protected $connection = 'mongodb';

    public function user()
    {
        return $this->belongsTo(User::class);
    }
}