Mysql 尝试插入以下关系

正在尝试插入以下关系：

$currentPerson->fbevents()->attach($currentEvent);

$currentPerson是：

{
    "name": "xxxx",
    "userId": "yyyyyyy",
    "pictureUrl": "zzzzz"
}

显示$currentPerson没有id，即使它刚刚通过$currentPerson->save插入数据库

所以，我想问题是如何在pivot表中获得正确的条目？模型如下：

User.php：

public function fbevents()
{
    return $this->belongsToMany('Fbevent', 'fbevent_user');
}

Fbevent.php：

public function users()
{
    return $this->belongsToMany('User', 'fbevent_user');
}

$currentPerson的类型为User，$currentEvent的类型为Fbevent

目前，我得到以下错误：

SQLSTATE[23000]: Integrity constraint violation: 1452 Cannot add or update a child row: a foreign key constraint fails (`dmf`.`fbevent_user`, CONSTRAINT `fbevent_user_fbevent_id_foreign` FOREIGN KEY (`fbevent_id`) REFERENCES `fbevents` (`id`) ON DELETE CASCADE) (SQL: insert into `fbevent_user` () values ())

迁移模式：

Schema::create('users', function(Blueprint $table) {
    $table->increments('id');
    $table->string('userId');
    $table->string('name');
    $table->string('pictureUrl');
    $table->timestamps();
});

Schema::create('fbevents', function(Blueprint $table) {
    $table->increments('id');
    $table->string('eventId');
    $table->string('pageId');
    $table->string('title');
    $table->string('description', 500);
    $table->datetime('start');
    $table->datetime('end');
    $table->string('picture');
    $table->timestamps();
});

FBU事件用户：

Schema::create('fbevent_user', function(Blueprint $table) {
    $table->increments('id');
    $table->integer('fbevent_id')->unsigned()->index();
    $table->foreign('fbevent_id')->references('id')->on('fbevents')->onDelete('cascade');
    $table->integer('user_id')->unsigned()->index();
    $table->foreign('user_id')->references('id')->on('users')->onDelete('cascade');
    $table->timestamps();
});

只需将“附加”替换为“保存”

---

在创建这些条目的位置显示表模式和实际代码。我已经添加了模式-代码与我所说的一样，只是$currentPerson->save；，正确输入用户和id等，然后$currentPerson->fbevents->attach$currentEvent；。谢谢你的帮助。是的，$currentEvent是什么？看起来你需要调用$currentEvent->save。确保事件和人员都已保存后，确保两者都具有id的echo$currentEvent->id；echo$currentPerson->id；。然后，您应该能够使用$currentPerson->fbevents->attach$currentEvent；将它们插入透视表；。

$currentPerson->save();
$currentPerson->fbevents()->save($currentEvent);