# STI Problem

**URL:** <https://www.ruby-forum.com/t/sti-problem/168650>\
**Category:** Rails\
**Created:** [May 23, 2009, 1:02pm UTC](https://www.ruby-forum.com/t/sti-problem/168650 "2009-05-23T13:02:27Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![nico](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/n/b5a626/32.png) [@nico](https://www.ruby-forum.com/u/nico)\
**Post date:** [May 23, 2009, 1:02pm UTC](https://www.ruby-forum.com/t/sti-problem/168650/1 "2009-05-23T13:02:27Z")

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Hi,

I’m having trouble with some STI Classes in a test.

When I create a new Class of an STI derived base class  
the type column is not set.

If I do

object = DerivedClass.create!(params)

then object[:type] == nil for some reason.

Any ideas why this is so? I assumed rails takes  
care of setting the type column in STI (that’s what I read).

Nico

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<div class="post-metadata">

**Author:** ![nico](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/n/b5a626/32.png) [@nico](https://www.ruby-forum.com/u/nico)\
**Post date:** [May 25, 2009, 9:03am UTC](https://www.ruby-forum.com/t/sti-problem/168650/2 "2009-05-25T09:03:26Z")

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Ooops, solved it! Was a problem with a migration…