在Laravel的Eloquent ORM中使用查找表：不是唯一的表别名？

Question

I've been trying to use Eloquent for an application I'm making (being proted from Codeigniter) but I can't get it to work.

I have 3 tables:

• users
• departments
• department_members (this is the lookup table)

department_members has 3 fields: id, department_id and user_id. All my tables have their own models. When I try to use the ORM to get the department of an user ( User::find(1)->member()->first() ) all I get is this error:

SQLSTATE[42000]: Syntax error or access violation: 1066 Not unique table/alias: 'users'

Although I know what the problem is, I don't know how to solve it, since it's all generated by the ORM.

The models:

• Member model

   class Member extends Eloquent { public static $table = 'department_members'; public static $timestamps = false; public function user() { return $this->has_many_and_belongs_to('User', 'users'); } } 

• User model

   class User extends Eloquent { public static $timestamps = false; public function member() { return $this->has_many_and_belongs_to('Member', 'department_members'); } } 

• Department model

   class Department extends Eloquent { public function member() { return $this->has_many_and_belongs_to('Member', 'department_members'); } } 

The columns have appropiate names: id as PK, and the respective names with _id appended.

If more info is needed I would be happy to help out.

Answer 1

You've setup your relationships incorrectly. You don't need to have a member model - just a User, and Department model.

Like so:

# in User
public function departments() {
    return $this->has_many_and_belongs_to('Department', 'department_members');
}

# in Department
public function users() {
    return $this->has_many_and_belongs_to('User', 'department_members');
}

There's no need for the additional model. Additionally, you might want to read here: http://laravel.com/docs/database/eloquent#many-to-many - of special note is the pivot tables, in case you want to do some extra work on the join table aspect of the relationship.