Laravel 4 BelongsToMany sync（）方法无法正常工作

Question

使用sync（）方法时出现问题。请帮我在这里。

我有三个表如下。

表：tbl_roles

+----------------+------------------+------+-----+---------+----------------+ 
| Field   | Type    | Null | Key | Default | Extra   | 
+----------------+------------------+------+-----+---------+----------------+ 
| id_role  | int(10) unsigned | NO | PRI | NULL | auto_increment | 
| name   | varchar(60)  | NO | UNI | NULL |    | 
| description | text    | YES |  | NULL |    | 
+----------------+------------------+------+-----+---------+----------------+ 

表：tbl_permissions

+----------------+------------------+------+-----+---------+----------------+ 
| Field   | Type    | Null | Key | Default | Extra   | 
+----------------+------------------+------+-----+---------+----------------+ 
| id_permission | int(10) unsigned | NO | PRI | NULL | auto_increment | 
| name   | varchar(255)  | NO |  | NULL |    | 
| description | text    | YES |  | NULL |    | 
+----------------+------------------+------+-----+---------+----------------+ 

表：tbl_link_roles_permissions

+---------------+------------------+------+-----+---------+-------+ 
| Field   | Type    | Null | Key | Default | Extra | 
+---------------+------------------+------+-----+---------+-------+ 
| id_role  | int(10) unsigned | NO | MUL | NULL |  | 
| id_permission | int(10) unsigned | NO | MUL | NULL |  | 
+---------------+------------------+------+-----+---------+-------+ 

我创造了许多给角色和权限模型之间的多对多关系。

榜样：

class Role extends Eloquent 
{ 
    /** 
    * Permissions 
    */ 
    public function permissions() 
    { 
     return $this->belongsToMany('Permission', 'tbl_link_roles_permissions', 'id_role', 'id_role'); 
    } 
} 

权限模型：

class Permission extends Eloquent 
{ 
    /** 
    * Roles 
    */ 
    public function roles() 
    { 
     return $this->belongsToMany('Role', 'tbl_link_roles_permissions', 'id_permission', 'id_permission'); 
    } 
} 

当我运行下面的代码同步角色的权限。它给我一个完整性约束违规错误。

验证码：

$role = Role::find($id_role); 

    $permissions = Input::get('role_permissions'); 

    /* 
    * Permissions array is like array('1','2','3') 
    * So I convert the value to integer. 
    */ 
    $parameters = array(); 

    foreach($permissions as $permission) { 
     $parameters[] = intval($permission); 
    } 

    $role->permissions()->sync($parameters); 

根据错误信息，我发现SQL查询是不正确的。

错误meesage：

SQLSTATE[23000]: Integrity constraint violation: 1452 Cannot add or update a child row: 
a foreign key constraint fails (`quidz_host_laravel`.`tbl_link_roles_permissions`, 
CONSTRAINT `tbl_link_roles_permissions_id_permission_foreign` FOREIGN KEY 
(`id_permission`) REFERENCES `tbl_permissions` (`id_permission`)) (SQL: insert into 
`tbl_link_roles_permissions` (`id_role`) values (?)) (Bindings: array (0 => 1,)) 

它只是插入id_role。这不是我想要的。谁能告诉我我做错了什么？

非常感谢。

Answer 1

我已经解决了我的问题。这是由建立关系时传递错误参数引起的。

的关系应该是这样的代码如下：

class Role extends Eloquent 
{ 
    /** 
    * Permissions 
    */ 
    public function permissions() 
    { 
     return $this->belongsToMany('Permission', 'tbl_link_roles_permissions', 'id_role', 'id_permission'); 
    } 
} 

class Permission extends Eloquent 
{ 
    /** 
    * Roles 
    */ 
    public function roles() 
    { 
     return $this->belongsToMany('Role', 'tbl_link_roles_permissions', 'id_permission', 'id_role'); 
    } 
}