# STI vs Polymorphic Associations

**URL:** <https://www.ruby-forum.com/t/sti-vs-polymorphic-associations/118456>\
**Category:** Rails\
**Created:** [October 27, 2007, 4:19am UTC](https://www.ruby-forum.com/t/sti-vs-polymorphic-associations/118456 "2007-10-27T04:19:14Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![bparanj](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/b/e9a140/32.png) [@bparanj](https://www.ruby-forum.com/u/bparanj)\
**Post date:** [October 27, 2007, 4:19am UTC](https://www.ruby-forum.com/t/sti-vs-polymorphic-associations/118456/1 "2007-10-27T04:19:14Z")

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I have a MasterEvent model. It has attributes that is required by  
another model Event. The user selects the MasterEvent model and I  
create the Event model by merging the attributes of the selected  
MasterEvent with the attributes that were presented for the Event  
model in the form.

I have association declarations in the MasterEvent and Event models.  
If I use STI does the subclasses inherit the association declarationed  
in a superclass? Should I use polymorphic associations? I read the AWD  
book but still not clear on these issues. TIA.