外键约束在laravel 7中的格式不正确

我正在使用laravel构建一个酒店管理应用程序。我试图在laravel中创建表'reservations'，但是当我运行'migrate:fresh'命令时，我得到以下结果：错误“外键约束格式不正确”。有人能说出你说的这个错误是什么意思吗

错误消息

  SQLSTATE[HY000]: General error: 1005 Can't create table `hotelplex`.`reservations` (errno: 150 "Foreign key constraint is incorrectly formed") (SQL: alter table `reservations` add constraint `reservations_reservations_user_id_foreign` foreign key (`reservations_user_id`) references `users` (`id`) on delete cascade)

          at C:\xampp\htdocs\hotelplex\vendor\laravel\framework\src\Illuminate\Database\Connection.php:669
            665|         // If an exception occurs when attempting to run a query, we'll format the error
            666|         // message to include the bindings with SQL, which will make this exception a
            667|         // lot more helpful to the developer instead of just the database's errors.
            668|         catch (Exception $e) {
          > 669|             throw new QueryException(
            670|                 $query, $this->prepareBindings($bindings), $e
            671|             );
            672|         }
            673| 

          1   C:\xampp\htdocs\hotelplex\vendor\laravel\framework\src\Illuminate\Database\Connection.php:463
              PDOException::("SQLSTATE[HY000]: General error: 1005 Can't create table `hotelplex`.`reservations` (errno: 150 "Foreign key constraint is incorrectly formed")")

          2   C:\xampp\htdocs\hotelplex\vendor\laravel\framework\src\Illuminate\Database\Connection.php:463
              PDOStatement::execute()

$table->unsignedInteger('user_id'); 
$table->unsignedInteger('room_type_id');

$table->unsignedBigInteger('user_id');
$table->unsignedBigInteger('room_type_id');

->onDelete（'cascade'）应位于结构创建部分

更改为：

public function up()
{
    Schema::create('reservations', function (Blueprint $table) {
        // Structure
        $table->id();
        $table->integer('uid')->unique();
        $table->timestamp('date');
        $table-> unsignedBigInteger('user_id')->onDelete('cascade');
        $table-> unsignedBigInteger('room_type_id')->onDelete('cascade');
        $table->integer('adults')->default(1);
        $table->integer('kids')->default(0);
        $table->date('check_in');
        $table->date('check_out');
        $table->integer('number_of_room')->default(1);
        $table->enum('status',['PENDING','CANCEL','SUCCESS'])->default('PENDING');
        $table->timestamps();

        // Relationships
        $table->foreign('user_id')->references('id')->on('users');
        $table->foreign('room_type_id')->references('id')->on('room_types');
    });
}

问题似乎是用户id和房间id的数据类型不匹配

$table->id（）；$table->bigIncrements（'id'）别名的别名


因此，您需要有关预订的“外国
用户id
和
房间类型\u id
列，如：

public function up()
{
    Schema::create('reservations', function (Blueprint $table) {
        // Structure
        $table->id();
        ...
        $table->unsignedBigInteger('user_id');
        $table->unsignedBigInteger('room_type_id');
        ...
        $table->foreign('user_id')->references('id')->on('users')->onDelete('cascade');
         $table->foreign('room_type_id')->references('id')->on('room_types')->onDelete('cascade');
            ...
         })
    }

Laravel6

Laravel6
没有任何方法
id（）
在表中创建
id
<代码>Laravel7

不执行。。我尝试使用

Laravel6

创建

id

并得到以下错误

似乎您发布了错误的错误，或者您已经在表中手动创建了

id

您可以使用

大增量

，

大整数

，

增量

，

整数

等

您可以找到所有可用的方法

Laravel7

根据

Laravel7

$table->id（）

是

$table->bigIncrements（'id'）

的别名，即

无符号大整数

要创建

外键

，

子列

的数据类型必须与

父列

完全匹配

由于

users.id

和

room\u-types.id

是一个

大增量

，那么

reservations.user\u-id

和

reservations.room\u-type\u-id

也需要是一个

无符号大整数

，而不是

无符号整数

所以要让它发挥作用

改变

  SQLSTATE[HY000]: General error: 1005 Can't create table `hotelplex`.`reservations` (errno: 150 "Foreign key constraint is incorrectly formed") (SQL: alter table `reservations` add constraint `reservations_reservations_user_id_foreign` foreign key (`reservations_user_id`) references `users` (`id`) on delete cascade)

          at C:\xampp\htdocs\hotelplex\vendor\laravel\framework\src\Illuminate\Database\Connection.php:669
            665|         // If an exception occurs when attempting to run a query, we'll format the error
            666|         // message to include the bindings with SQL, which will make this exception a
            667|         // lot more helpful to the developer instead of just the database's errors.
            668|         catch (Exception $e) {
          > 669|             throw new QueryException(
            670|                 $query, $this->prepareBindings($bindings), $e
            671|             );
            672|         }
            673| 

          1   C:\xampp\htdocs\hotelplex\vendor\laravel\framework\src\Illuminate\Database\Connection.php:463
              PDOException::("SQLSTATE[HY000]: General error: 1005 Can't create table `hotelplex`.`reservations` (errno: 150 "Foreign key constraint is incorrectly formed")")

          2   C:\xampp\htdocs\hotelplex\vendor\laravel\framework\src\Illuminate\Database\Connection.php:463
              PDOStatement::execute()

$table->unsignedInteger('user_id'); 
$table->unsignedInteger('room_type_id');

$table->unsignedBigInteger('user_id');
$table->unsignedBigInteger('room_type_id');

至

  SQLSTATE[HY000]: General error: 1005 Can't create table `hotelplex`.`reservations` (errno: 150 "Foreign key constraint is incorrectly formed") (SQL: alter table `reservations` add constraint `reservations_reservations_user_id_foreign` foreign key (`reservations_user_id`) references `users` (`id`) on delete cascade)

          at C:\xampp\htdocs\hotelplex\vendor\laravel\framework\src\Illuminate\Database\Connection.php:669
            665|         // If an exception occurs when attempting to run a query, we'll format the error
            666|         // message to include the bindings with SQL, which will make this exception a
            667|         // lot more helpful to the developer instead of just the database's errors.
            668|         catch (Exception $e) {
          > 669|             throw new QueryException(
            670|                 $query, $this->prepareBindings($bindings), $e
            671|             );
            672|         }
            673| 

          1   C:\xampp\htdocs\hotelplex\vendor\laravel\framework\src\Illuminate\Database\Connection.php:463
              PDOException::("SQLSTATE[HY000]: General error: 1005 Can't create table `hotelplex`.`reservations` (errno: 150 "Foreign key constraint is incorrectly formed")")

          2   C:\xampp\htdocs\hotelplex\vendor\laravel\framework\src\Illuminate\Database\Connection.php:463
              PDOStatement::execute()

$table->unsignedInteger('user_id'); 
$table->unsignedInteger('room_type_id');

$table->unsignedBigInteger('user_id');
$table->unsignedBigInteger('room_type_id');

像这样：

public function up()
    {
        Schema::create('reservations', function (Blueprint $table) {
            $table->id();
            $table->integer('uid')->unique();
            $table->timestamp('date');
            $table->unsignedBigInteger('user_id');
            $table->unsignedBigInteger('room_type_id');
            $table->integer('adults')->default(1);
            $table->integer('kids')->default(0);
            $table->date('check_in');
            $table->date('check_out');
            $table->integer('number_of_room')->default(1);
            $table->enum('status',['PENDING','CANCEL','SUCCESS'])->default('PENDING');
            $table->timestamps();
            $table->foreign('user_id')->references('id')->on('users')->onDelete('cascade');
            $table->foreign('room_type_id')->references('id')->on('room_types')->onDelete('cascade');
        });
    }

---

在laravel 8上，您可以使用

$table->id();
....
$table->unsignedBigInteger('user_id');            
$table->unsignedBigInteger('room_type_id');
...
$table->timestamps();
$table->foreign('user_id')->references('id')->on('users')->onDelete('restrict');
$table->foreign('room_type_id')->references('id')->on('room_types')->onDelete('restrict');

---

根据截至6日它所做的文档

$table->id（）；$table->bigIncrements（'id'）的别名

$table->id（）；在拉雷维尔有售6@jeremykenedy它在Laravel6中不可用，但在Laravel7@HarshithVA它在Laravel6中不可用，在Laravel7中可用–我真的很抱歉你是对的，它在Laravel7中可用。