为什么我的外键在迁移时不起作用 - Laravel

Question

我正在尝试在 Laravel 中进行新的数据库迁移，但它似乎被困在创建外键上。它会产生以下错误。

errno: 150 "Foreign key constraint is incorrectly formed"

我已经找到了这篇文章Laravel migration (errno: 150 "Foreign key constraint is incorrectly formed")，但是我使用了带有 unsignedBigInteger 的 bigIncrements，这样应该可以正常工作吗？而且我在之前的项目中也做了同样的事情，而且效果很好。

Dropped all tables successfully.
Migration table created successfully.
Migrating: 2014_10_12_000000_create_users_table
Migrated:  2014_10_12_000000_create_users_table (0.42 seconds)
Migrating: 2014_10_12_100000_create_password_resets_table
Migrated:  2014_10_12_100000_create_password_resets_table (1.05 seconds)
Migrating: 2019_08_19_000000_create_failed_jobs_table
Migrated:  2019_08_19_000000_create_failed_jobs_table (0.65 seconds)
Migrating: 2019_10_23_110756_create_campaigns_table

它似乎停留在活动表中的$table->foreign('game_id')->references('id')->on('games'); 上，这很奇怪，因为它可以很好地处理$table->foreign('user_id')->references('id')->on('users');？当我注释掉 game_id 外键时，它会很好地迁移所有表吗？可能是因为游戏桌尚未创建吗？我将如何解决这个问题？

游戏迁移

<?php

use Illuminate\Database\Migrations\Migration;
use Illuminate\Database\Schema\Blueprint;
use Illuminate\Support\Facades\Schema;

class CreateGamesTable extends Migration
{
    /**
     * Run the migrations.
     *
     * @return void
     */
    public function up()
    {
        Schema::create('games', function (Blueprint $table) {
            $table->bigIncrements('id');
            $table->timestamps();
        });
    }

    /**
     * Reverse the migrations.
     *
     * @return void
     */
    public function down()
    {
        Schema::dropIfExists('games');
    }
}

广告系列迁移

<?php

use Illuminate\Database\Migrations\Migration;
use Illuminate\Database\Schema\Blueprint;
use Illuminate\Support\Facades\Schema;

class CreateCampaignsTable extends Migration
{
    /**
     * Run the migrations.
     *
     * @return void
     */
    public function up()
    {
        Schema::create('campaigns', function (Blueprint $table) {
            $table->bigIncrements('id');
            $table->string('name');
            $table->longText('settings');
            $table->longText('preview_settings');
            $table->text("description")->nullable();
            $table->enum('type', ['desktop', 'appstore', 'facebook', 'messenger', 'playstore', 'mobile']);
            $table->enum('published', ['Draft', 'Ready', 'Live']);
            $table->datetime("start_time")->nullable();
            $table->datetime("end_time")->nullable();
            $table->timestamps();
            $table->unsignedBigInteger('user_id');
            $table->unsignedBigInteger('game_id');
            $table->foreign('user_id')->references('id')->on('users');
            $table->foreign('game_id')->references('id')->on('games');
        });
    }

    /**
     * Reverse the migrations.
     *
     * @return void
     */
    public function down()
    {
        Schema::dropIfExists('campaigns');
    }
}

用户迁移

<?php

use Illuminate\Database\Migrations\Migration;
use Illuminate\Database\Schema\Blueprint;
use Illuminate\Support\Facades\Schema;

class CreateUsersTable extends Migration
{
    /**
     * Run the migrations.
     *
     * @return void
     */
    public function up()
    {
        Schema::create('users', function (Blueprint $table) {
            $table->bigIncrements('id');
            $table->string('name');
            $table->string('email')->unique();
            $table->timestamp('email_verified_at')->nullable();
            $table->string('password');
            $table->rememberToken();
            $table->timestamps();
        });
    }

    /**
     * Reverse the migrations.
     *
     * @return void
     */
    public function down()
    {
        Schema::dropIfExists('users');
    }
}

Answer 1

因为活动表已创建，但游戏表尚未创建。

迁移按顺序进行。

查看列表，游戏迁移不显示；

Migrating: 2014_10_12_000000_create_users_table
Migrated:  2014_10_12_000000_create_users_table (0.42 seconds)
Migrating: 2014_10_12_100000_create_password_resets_table
Migrated:  2014_10_12_100000_create_password_resets_table (1.05 seconds)
Migrating: 2019_08_19_000000_create_failed_jobs_table
Migrated:  2019_08_19_000000_create_failed_jobs_table (0.65 seconds)
Migrating: 2019_10_23_110756_create_campaigns_table

你能用这种方式编辑和尝试代码吗？

游戏迁移；

<?php

use Illuminate\Database\Migrations\Migration;
use Illuminate\Database\Schema\Blueprint;
use Illuminate\Support\Facades\Schema;

class CreateGamesTable extends Migration
{
    /**
     * Run the migrations.
     *
     * @return void
     */
    public function up()
    {
        Schema::create('games', function (Blueprint $table) {
            $table->bigIncrements('id');
            $table->timestamps();
        });

    Schema::table('campaigns', function(Blueprint $table)
    {
        $table->foreign('game_id')->references('id')->on('games');
    });

    }

    /**
     * Reverse the migrations.
     *
     * @return void
     */
    public function down()
    {
        Schema::dropIfExists('games');
    }
}

广告系列迁移；

<?php

use Illuminate\Database\Migrations\Migration;
use Illuminate\Database\Schema\Blueprint;
use Illuminate\Support\Facades\Schema;

class CreateCampaignsTable extends Migration
{
    /**
     * Run the migrations.
     *
     * @return void
     */
    public function up()
    {
        Schema::create('campaigns', function (Blueprint $table) {
            $table->bigIncrements('id');
            $table->string('name');
            $table->longText('settings');
            $table->longText('preview_settings');
            $table->text("description")->nullable();
            $table->enum('type', ['desktop', 'appstore', 'facebook', 'messenger', 'playstore', 'mobile']);
            $table->enum('published', ['Draft', 'Ready', 'Live']);
            $table->datetime("start_time")->nullable();
            $table->datetime("end_time")->nullable();
            $table->timestamps();
            $table->unsignedBigInteger('user_id');
            $table->unsignedBigInteger('game_id');
            $table->foreign('user_id')->references('id')->on('users');
        });
    }

    /**
     * Reverse the migrations.
     *
     * @return void
     */
    public function down()
    {
        Schema::dropIfExists('campaigns');
    }
}

Answer 2

$table->bigInteger('user_id')->unsigned();
$table->bigInteger('game_id')->unsigned();