SQLSTATE\[23000\]：违反完整性约束：1452 无法添加或更新子行：外键约束失败 - Laravel

Question

我知道这个问题已经被问过了，但我仍然找不到我做错了什么。

我正在使用 Laravel 框架。

我有 2 个表（用户和位置）。当我想创建一个用户时，我收到错误消息：

SQLSTATE[23000]: Integrity constraint violation: 1452 Cannot add or update a child row: a foreign key constraint fails ( festival_aid . users , CONSTRAINT fk_users_locations1 FOREIGN KEY ( location_id ) REFERENCES locations ( location_id ) ON DELETE CASCADE ON UPDATE NO ACTION) (SQL: insert into users ( user_id , user_email , location_id ) 值 (?, ?, ?)) (‘testindings =>1. com’, 2 => ‘1’, ))

表用户

CREATE TABLE IF NOT EXISTS `festival_aid`.`users` (
  `user_id` BIGINT NOT NULL AUTO_INCREMENT,
  `user_email` VARCHAR(45) NOT NULL,
  `user_created` TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
  `user_modified` TIMESTAMP NULL,
  `user_deleted` TIMESTAMP NULL,
  `user_lastlogin` TIMESTAMP NULL,
  `user_locked` TIMESTAMP NULL,
  `location_id` BIGINT NOT NULL,
  PRIMARY KEY (`user_id`),
  UNIQUE INDEX `user_email_UNIQUE` (`user_email` ASC),
  CONSTRAINT `fk_users_locations1`
    FOREIGN KEY (`location_id`)
    REFERENCES `festival_aid`.`locations` (`location_id`)
    ON DELETE CASCADE
    ON UPDATE NO ACTION,
ENGINE = InnoDB;

表位置

DROP TABLE IF EXISTS `festival_aid`.`locations` ;

CREATE TABLE IF NOT EXISTS `festival_aid`.`locations` (
  `location_id` BIGINT NOT NULL AUTO_INCREMENT,
  `location_latitude` FLOAT NOT NULL,
  `location_longitude` FLOAT NOT NULL,
  `location_desc` VARCHAR(255) NULL,
  `location_type` VARCHAR(45) NULL,
  PRIMARY KEY (`location_id`))
ENGINE = InnoDB;

迁移用户

public function up()
    {
        Schema::table('users', function(Blueprint $table)
        {
            $table->increments('user_id');
            $table->string('user_email');
            $table->timestamp('user_created');
            $table->timestamp('user_modified');
            $table->timestamp('user_deleted');
            $table->timestamp('user_lastlogin');
            $table->timestamp('user_locked');

            $table->foreign('location_id')
                ->references('id')->on('locations');
            //->onDelete('cascade');
        });
    }

迁移地点

public function up()
    {
        Schema::table('locations', function(Blueprint $table)
        {
            $table->primary('location_id');
            $table->float('location_latitude');
            $table->float('location_longitude');
            $table->string('location_desc');
            $table->string('location_type');
        });
    }

模型用户

public function location()
    {
        return $this->belongsTo('Location');
    }

模型位置

 public function user()
    {
        return $this->hasOne('User');
    }

控制器

public function store()
    {
        $input = Input::all();

        $rules = array('user_email' => 'required|unique:users|email');

        $v = Validator::make($input, $rules);

        if($v->passes())
        {
            $user = new User();
            $location = new Location();

            $user->user_email = $input['user_email'];
            //$user->location_id = $input['location_id'];

            $location->location_latitude = $input['location_latitude'];
            $location->location_longitude = $input['location_longitude'];

            $user->save();
            $location->save();
    }

我似乎找不到我做错了什么。显然外键有问题。

原文由 Gilko 发布，翻译遵循 CC BY-SA 4.0 许可协议

Answer 1

用户行需要对有效位置的引用。在保存用户之前，该位置必须可用。因此，首先保存位置，然后保存用户并取消注释 $user->location_id 行，你就完成了。

原文由 Haneev 发布，翻译遵循 CC BY-SA 3.0 许可协议

Answer 2

如果用户表没有记录，那么您将面临与之前相同的错误。您可以在运行迁移之前设置任何默认值

原文由 Muhammad Ahmad 发布，翻译遵循 CC BY-SA 4.0 许可协议