Laravel 4 BelongsToMany sync() method doesn't work properly - laravel

Question

I have problem when using sync() method. Please help me out here.
I have three tables as below.
Table: 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 | |
+----------------+------------------+------+-----+---------+----------------+
Table: 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 | |
+----------------+------------------+------+-----+---------+----------------+
Table: 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 | |
+---------------+------------------+------+-----+---------+-------+
I have created many to many relationship between roles and permissions models.
Role model:
class Role extends Eloquent
{
/**
* Permissions
*/
public function permissions()
{
return $this->belongsToMany('Permission', 'tbl_link_roles_permissions', 'id_role', 'id_role');
}
}
Permission model:
class Permission extends Eloquent
{
/**
* Roles
*/
public function roles()
{
return $this->belongsToMany('Role', 'tbl_link_roles_permissions', 'id_permission', 'id_permission');
}
}
When I run the following code to sync roles' permissions. It give me an Integrity constraint violation error.
The Code:
$role = Role::find($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);
According to the error message, I found the SQL query is not correct.
Error 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, ))
It only inserts id_role. This is not what I want. Can anyone tell me what I did wrong?
Thanks a lot.

Answer 1

I have solved my problem. It's caused by passing wrong parameters when building the relationships.
The relationship should be like the code below:
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');
}
}