# Rails 3.0 and counter\_cache error

**URL:** <https://www.ruby-forum.com/t/rails-3-0-and-counter-cache-error/193104>\
**Category:** Rails\
**Created:** [August 11, 2010, 11:26am UTC](https://www.ruby-forum.com/t/rails-3-0-and-counter-cache-error/193104 "2010-08-11T11:26:26Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![casper\_the\_ghost](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/c/58956e/32.png) [@casper\_the\_ghost](https://www.ruby-forum.com/u/casper_the_ghost)\
**Post date:** [August 11, 2010, 11:26am UTC](https://www.ruby-forum.com/t/rails-3-0-and-counter-cache-error/193104/1 "2010-08-11T11:26:26Z")

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Hello,  
I’m working on a rails 3.0 project and today I tried to add a counter  
cache column, but I keep getting this error:

ArgumentError: Unknown key(s): counter\_cache

This happens with any combinations of rails 3.0 beta4, rc, ruby 1.8.7  
and 1.9.2.

Regards  
Andrea