Laravel hasMany关系自定义选择结果为空

Question

我有表格，用户，个人资料，联系人。 1位用户有1个个人资料，1个个人资料有很多联系人，我想获取包含过滤后的联系人和所选列的个人资料（我不希望获得所有列）。我在下面编码成功了

UserController.php

$profile = $user->with(['profile.emails', 'profile.phones'])->first();

User.php

public function profile()
{
    return $this->hasOne(Profile::class);
}

Profile.php

public function emails()
{
    return $this->hasMany(Contact::class)
        ->where('type', 'email');
}

public function phones()
{
    return $this->hasMany(Contact::class)
        ->where('type', 'phone');
}

这样的结果数据

{
    "username": "user",
    "email": "user@mail.com",
    "profile": {
        "first_name": "Alex",
        "last_name": "Ariana",
        "emails": [
            {
                "id": 1,
                "profile_id": 1,
                "type": "email",
                "prefix": "Personal",
                "value": "alex@mail.com",
                "is_primary": 0,
            },
            {
                "id": 2,
                "profile_id": 1,
                "type": "email",
                "prefix": "Business",
                "value": "business@mail.com",
                "is_primary": 1,
            }
        ],
        "phones": [
            {
                "id": 3,
                "profile_id": 1,
                "type": "phone",
                "prefix": "45",
                "value": "564637345345",
                "is_primary": 1,
            }
        ]
    }
}

但随后我在这种关系上添加选择

    public function emails()
    {
        return $this->hasMany(Contact::class)
            ->select([DB::raw('IFNULL(prefix, "Email") AS type'), 'value AS url', 'is_primary'])
            ->where('type', 'email');
    }

    public function phones()
    {
        return $this->hasMany(Contact::class)
            ->select(['prefix', 'value AS number', 'is_primary'])
            ->where('type', 'phone');
    }

然后我得到了这样的空联系人数据 {

"id": 1,
"username": "user",
"email": "user@mail.com",
"profile": {
    "first_name": "Alex",
    "last_name": "Ariana",
    "emails": [ ],
    "phones": [ ]
}

}

为什么会发生这种情况？如果我通过hasManyThrough从用户那里访问了它，但是当我使用hasMany时，它为空。