在MySQL中错误地形成了外键约束：Laravel迁移

Question

我的迁移是

Schema::create('user_details', function (Blueprint $table) {
    $table->Increments('id')->unique();
    $table->text('detail');
    $table->text('value');
    $table->integer('user_id');
    $table->timestamps();

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

和

Schema::create('users', function (Blueprint $table) {
    $table->Increments('id')->unique();
    $table->integer('user_detail_id');
    $table->integer('user_setting_id');
    $table->integer('company_id');
    $table->mediumText('role');
    $table->mediumText('email')->unique();
    $table->mediumText('password');
    $table->timestamps();
});

[当我尝试迁移时，出现此错误消息：

errno：150“外键约束格式不正确”（SQL：alter表user_details添加约束user_details_user_id_foreign外键（user_id）引用users（id））

为什么会这样？

Answer 1

您需要为表设置InnoDB存储引擎。您可以在模式构建器中进行此操作：$table->engine = 'InnoDB';或在config/database.php文件（connections => mysql => engine）中：将'engine' => null,更改为'engine' => 'InnoDB',。

第二，定义为$table->increments('id');的主键是自动递增的UNSIGNED INTEGER。并且您的外键应该未签名。了解有关creating columns的更多信息。

Schema::create('user_details', function (Blueprint $table) {
    $table->engine = 'InnoDB';

    $table->increments('id');
    $table->text('detail');
    $table->text('value');
    $table->unsignedInteger('user_id');
    $table->timestamps();

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

Schema::create('users', function (Blueprint $table) {
    $table->engine = 'InnoDB';

    $table->increments('id');
    $table->integer('user_detail_id');
    $table->integer('user_setting_id');
    $table->integer('company_id');
    $table->mediumText('role');
    $table->mediumText('email')->unique();
    $table->mediumText('password');
    $table->timestamps();
});