# Dummy field in a model

**URL:** <https://www.ruby-forum.com/t/dummy-field-in-a-model/64456>\
**Category:** Rails\
**Created:** [June 26, 2006, 12:52am UTC](https://www.ruby-forum.com/t/dummy-field-in-a-model/64456 "2006-06-26T00:52:58Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![pratik](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/p/4bbf92/32.png) [@pratik](https://www.ruby-forum.com/u/pratik)\
**Post date:** [June 26, 2006, 12:52am UTC](https://www.ruby-forum.com/t/dummy-field-in-a-model/64456/1 "2006-06-26T00:52:58Z")

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I want to have a field in model, which I’m not storing in a database.  
And I want to do something like the following in the model code :

validates\_format\_of :field\_NOT\_in\_db, :with =\> session[:field]

How can I do it ?

Thanks,  
Pratik

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<div class="post-metadata">

**Author:** ![pratik](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/p/4bbf92/32.png) [@pratik](https://www.ruby-forum.com/u/pratik)\
**Post date:** [June 26, 2006, 2:12am UTC](https://www.ruby-forum.com/t/dummy-field-in-a-model/64456/2 "2006-06-26T02:12:32Z")

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Hi there,  
You may (or may not) also need to look into these articles which I  
found useful : Validating Non-AR objects…  
[http://www.realityforge.org/articles/2005/12/02/validations-for-non-activerecord-model-objects](http://www.realityforge.org/articles/2005/12/02/validations-for-non-activerecord-model-objects)  
and  
[http://wiki.rubyonrails.com/rails/pages/HowToUseValidationsWithoutExtendingActiveRecord](http://wiki.rubyonrails.com/rails/pages/HowToUseValidationsWithoutExtendingActiveRecord)

## Best Regards Eaden McKee

Webforce Ltd | www.webforce.co.nz

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<div class="post-metadata">

**Author:** ![pratik](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/p/4bbf92/32.png) [@pratik](https://www.ruby-forum.com/u/pratik)\
**Post date:** [June 26, 2006, 2:00am UTC](https://www.ruby-forum.com/t/dummy-field-in-a-model/64456/3 "2006-06-26T02:00:23Z")

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You might want attr\_accessor?

[http://www.phylomortis.com/resource/script/syntax/syn-aa.html](http://www.phylomortis.com/resource/script/syntax/syn-aa.html)

* * *

Timothy J.  
[www.foundinteractive.com](http://www.foundinteractive.com)

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<div class="post-metadata">

**Author:** ![pratik](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/p/4bbf92/32.png) [@pratik](https://www.ruby-forum.com/u/pratik)\
**Post date:** [June 26, 2006, 2:15am UTC](https://www.ruby-forum.com/t/dummy-field-in-a-model/64456/4 "2006-06-26T02:15:48Z")

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Simply, the agile book shows you how to create a simple login. You have  
a field password in the view that gets input into the model. you use  
attr\_accessor to tell the Model that it should allow that value to be  
passed into the Instance, but then you encrypt the password and store  
it in the DB as column “hashed\_password”. It couldn’t be simpler  
really.

* * *

Timothy J.  
[www.foundinteractive.com](http://www.foundinteractive.com)