# Error edit user view page

**URL:** <https://www.ruby-forum.com/t/error-edit-user-view-page/118908>\
**Category:** Rails\
**Created:** [November 1, 2007, 9:12am UTC](https://www.ruby-forum.com/t/error-edit-user-view-page/118908 "2007-11-01T09:12:31Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![remco](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/r/9d8465/32.png) [@remco](https://www.ruby-forum.com/u/remco)\
**Post date:** [November 1, 2007, 9:12am UTC](https://www.ruby-forum.com/t/error-edit-user-view-page/118908/1 "2007-11-01T09:12:31Z")

</div>

Hi there…

I have created a table and a join table

class CreateArrangements \< ActiveRecord::Migration  
def self.up  
create\_table :arrangements do |t|  
t.column :name, :string  
end  
end

def self.down  
drop\_table :arrangements  
end  
end

**Join table** \*\*\*\*\*\*\*\*\*\*

class AddTableArragementUsers \< ActiveRecord::Migration  
def self.up  
create\_table :arrangements\_users, :id =\> false do |t|  
t.column :arrangement\_id, :integer, :null =\> false  
t.column :user\_id, :integer, :null =\> false

end  
add\_index “arrangements\_users”, “arrangement\_id”  
add\_index “arrangements\_users”, “user\_id”  
end

def self.down  
end  
end

* * *

In the user-edit-view page a put in the following code:

arrangement  
\<%= select\_tag 'user[arrangement\_ids][]', options\_from\_collection\_for\_select(@arrangement, :id, :name, @user.arrangements.collect{|arrangement| arrangement.id}), { :multiple =\> true, :size =\> 5 }%\>

But i get the following error

You have a nil object when you didn’t expect it!  
You might have expected an instance of Array.  
The error occurred while evaluating nil.inject

Anyone idea?

Swoany