SQLSTATE[HY000]: General error: 1005 Can't create table `test`.`members` (errno: 150 "Foreign key constraint is incorrectly formed")

Question

我在 Laravel 中使用迁移来创建 table 之间的关系，我有 4 个 table：用户、成员、member_skills、和技能。我有以下用户代码 table:

public function up()
{
    Schema::create('users', function (Blueprint $table) {
        $table->id();
        $table->string('name');
        $table->string('email')->unique();
        $table->timestamp('email_verified_at')->nullable();
        $table->string('password');
        $table->rememberToken();
        $table->timestamps();
        $table->boolean('admin');
    });
}

成员table:

public function up()
{
    Schema::create('members', function (Blueprint $table) {
        $table->id();
        $table->timestamps();
        $table->string('name');
        $table->string('status');
        $table->date('date')->nullable();
        $table->text('project')->nullable();
        $table->date('start')->nullable();
        $table->foreign('name')->references('name')->on('users');
    });
}

member_skills table:

public function up()
{
    Schema::create('member_skills', function (Blueprint $table) {
        $table->id();
        $table->timestamps();
        $table->string('name');
        $table->string('skill');
        $table->foreign('name')->references('name')->on('members');
    });
}

和技能table:

public function up()
{
    Schema::create('skills', function (Blueprint $table) {
        $table->id();
        $table->timestamps();
        $table->string('skill');
        $table->text('description');
        $table->foreign('skill')->references('skill')->on('member_skills');
    });
}

但是，运行我的迁移结果是 (errno: 150 "Foreign key constraint is incorrectly formed")。我读到更改迁移顺序应该可以解决问题，所以我已经按照用户、成员、member_skills 和技能的顺序安排了 4 个 table 进行迁移，但我仍然收到同样的错误。我还有什么地方做错了吗？

Answer 1

这是正确的方法

public function up()
{
   Schema::create('members', function (Blueprint $table) {
      ...
      $table->unsignedBigInteger('user_id');
      $table->foreign('user_id')->references('id')->on('users');
   });
}

public function up()
{
   Schema::create('member_skills', function (Blueprint $table) {
      ...
      $table->unsignedBigInteger('member_id');
      $table->foreign('member_id')->references('id')->on('members');
   });
}

public function up()
{
   Schema::create('skills', function (Blueprint $table) {
      ...
      $table->unsignedBigInteger('member_skill_id');
      $table->foreign('member_skill_id')->references('id')->on('member_skills');
   });
}

更多：https://laravel.com/docs/8.x/migrations#foreign-key-constraints

Answer 2

您应该尝试使用成员 table 的 id 作为外键，而不是 name member_skills 架构

    public function up()
    {
        Schema::create('member_skills', function (Blueprint $table) {
            $table->id();
            $table->timestamps();
            $table->string('member_id');
            $table->string('skill');
            $table->foreign('member_id')->references('id')->on('members');
        });
    }

您收到此错误是因为您试图在成员 table 中引用 name，该成员已经是用户 table 的外键。

您可以通过 blade 中的 id 外键访问成员的 name。

SQLSTATE[HY000]: General error: 1005 Can't create table `test`.`members` (errno: 150 "Foreign key constraint is incorrectly formed")

SQLSTATE[HY000]: General error: 1005 Can't create table `test`.`members` (errno: 150 "Foreign key constraint is incorrectly formed")

mysql

database

database-migration

laravel

eloquent