Laravel 迁移错误 外键约束格式不正确

Question

这是每次显示的错误。

   Illuminate\Database\QueryException 

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

  1   G:\Laravel\CodeHacking\vendor\laravel\framework\src\Illuminate\Database\Connection.php:501
      PDOException::("SQLSTATE[HY000]: General error: 1005 Can't create table `codehacking`.`posts` (errno: 150 "Foreign key constraint is incorrectly formed"))
  2   G:\Laravel\CodeHacking\vendor\laravel\framework\src\Illuminate\Database\Connection.php:501
      PDOStatement::execute()

用户表

    public function up()
    {
        Schema::create('users', function (Blueprint $table) {
            $table->id();
            $table->integer('role_id')->index()->unsigned()->nullable();
            $table->integer('is_active')->default(0);
            $table->string('name');
            $table->string('email')->unique();
            $table->timestamp('email_verified_at')->nullable();
            $table->string('password');
            $table->rememberToken();
            $table->timestamps();
        });
    }

帖子表

    public function up()
    {
        Schema::create('posts', function (Blueprint $table) {
            $table->id();
            $table->integer('user_id')->unsigned()->index();
            $table->integer('category_id')->unsigned()->index();
            $table->integer('photo_id')->unsigned()->index();
            $table->string('title');
            $table->string('body');
            $table->timestamps();

            $table->foreign('user_id')->references('id')->on('users')->onDelete('cascade');
        });
    }

我每次尝试迁移表时都会出现此错误。如何解决它？ 该代码基于Laravel-9。每当我遇到此错误时，我都在尝试使用PHP Aritsan迁移命令创建表。

Answer 1

Schema::create('posts', function (Blueprint $table) {
            $table->id();
            $table->unsignedBigInteger('user_id')->nullable();
            $table->integer('category_id')->unsigned()->index();
            $table->integer('photo_id')->unsigned()->index();
            $table->string('title');
            $table->string('body');
            $table->timestamps();

            $table->foreign('user_id')->references('id')->on('users')->onDelete('cascade');
        });

Answer 2

我也有这个错误。当外键类型及其参考类型与不匹配时，此错误将处理。例如，如果外键类型为（int），但是参考密钥类型为（biginteger）此错误将处理。