無法在Laravel 5.2中使用外鍵遷移

Question

我想創建兩個表users和roles。我的代碼如下所示：

2014_10_12_000000_create_users_table.php

<?php 

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

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

      $table->foreign('role') 
       ->references('id') 
       ->on('roles'); 
     }); 
    } 

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

2016_03_09_004256_create_roles_table.php

<?php 

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

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

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

當我運行php artisan migrate下面的錯誤出現。

[Illuminate\Database\QueryException] SQLSTATE[HY000]: General error: 1005 Can't create table trucking . #sql-1240_44 (errno: 150 "Foreign key constraint is incorrectly formed") (SQL: alter table users add constraint u sers_role_foreign foreign key (role) references roles (id))

[PDOException] SQLSTATE[HY000]: General error: 1005 Can't create table trucking . #sql-1240_44 (errno: 150 "Foreign key constraint is incorrectly formed")

Answer 1

你應該確保，你roles表遷移之前users表遷移運行。默認情況下，在Laravel中，您已創建了users表遷移，因此，如果只是更改了其代碼並稍後添加roles遷移，它將無法工作。您應該更改users或roles遷移文件名，以確保roles表遷移文件的開始時間戳會在users表之前。

例如，你可能有這樣的情況：

2014_10_12_000000_create_users_table.php 
2015_10_12_123552_create_roles_table.php 

，你應該重命名文件有這樣的：

2015_10_12_123652_create_users_table.php 
2015_10_12_123552_create_roles_table.php 

當然我假設你只在開發過程中使用這些遷移而且還沒有投入生產。

Answer 2

public function up() 
    { 
     Schema::create('users', function (Blueprint $table) { 
      $table->increments('id'); 
      $table->string('firstname'); 
      $table->string('lastname'); 
      $table->text('slug'); 
      $table->string('email')->unique(); 
      $table->string('password', 60); 
      $table->decimal('fidbonus', 6, 2); 
      $table->rememberToken(); 
      $table->timestamps(); 
     }); 
     Schema::create('Userinfos', function (Blueprint $table) { 
      $table->increments('id'); 
      $table->integer('User_id')->unsigned(); 
      $table->foreign('User_id')->references('id')->on('Users'); 
      $table->string('address'); 
      $table->string('address2'); 
      $table->text('city'); 
      $table->string('zip'); 
      $table->string('country'); 
      $table->string('Phone'); 
      $table->timestamps(); 
     }); 
     Schema::create('password_resets', function (Blueprint $table) { 
      $table->string('email')->index(); 
      $table->string('token')->index(); 
      $table->timestamp('created_at'); 
     }); 
    } 

Answer 3

public function up() 
{ 
    Schema::create('users', function (Blueprint $table) { 
     $table->increments('id'); 
     $table->string('firstname'); 
     $table->string('lastname'); 
     $table->text('slug'); 
     $table->string('email')->unique(); 
     $table->string('password', 60); 
     $table->decimal('fidbonus', 6, 2); 
     $table->rememberToken(); 
     $table->timestamps(); 
    }); 
    Schema::create('Userinfos', function (Blueprint $table) { 
     $table->increments('id'); 
     //$table->integer('User_id')->unsigned(); 
     $table->unsignedInteger('User_id'); 
     //$table->foreign('User_id')->references('id')->on('Users'); 
     $table->foreign('User_id')->references('id')->on('Users')->onDelete('cascade')->onUpdate('cascade'); 
     $table->string('address'); 
     $table->string('address2'); 
     $table->text('city'); 
     $table->string('zip'); 
     $table->string('country'); 
     $table->string('Phone'); 
     $table->timestamps(); 
    }); 
    Schema::create('password_resets', function (Blueprint $table) { 
     $table->string('email')->index(); 
     $table->string('token')->index(); 
     $table->timestamp('created_at'); 
    }); 
} 

嘗試上文code.Its做工精細