# PGError "unknown column" on polymorphic association column

**URL:** <https://www.ruby-forum.com/t/pgerror-unknown-column-on-polymorphic-association-column/89264>\
**Category:** Rails\
**Created:** [March 19, 2007, 4:48am UTC](https://www.ruby-forum.com/t/pgerror-unknown-column-on-polymorphic-association-column/89264 "2007-03-19T04:48:51Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![fbeausoleil](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/f/ec9cab/32.png) [@fbeausoleil](https://www.ruby-forum.com/u/fbeausoleil)\
**Post date:** [March 19, 2007, 4:48am UTC](https://www.ruby-forum.com/t/pgerror-unknown-column-on-polymorphic-association-column/89264/1 "2007-03-19T04:48:51Z")

</div>

Hi all !

This is very strange. I am attempting to get my application running  
on PostgreSQL (from MySQL), and I get this error:

ActiveRecord::StatementInvalid: PGError: ERREUR: la colonne «Party»  
n’existe pas  
: SELECT \* FROM contact\_routes WHERE (routable\_type = “Party” AND  
routable\_id = 1000013) ORDER BY position DESC LIMIT 1  
/home/francois/src/xlsuite.org/vendor/rails/activerecord/lib/active\_record/connection\_adapters/abstract\_adapter.rb:128:in  
`log' /home/francois/src/xlsuite.org/vendor/rails/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb:152:in `execute’  
/home/francois/src/xlsuite.org/vendor/rails/activerecord/lib/active\_record/connection\_adapters/postgresql\_adapter.rb:433:in  
`select' /home/francois/src/xlsuite.org/vendor/rails/activerecord/lib/active_record/connection_adapters/abstract/database_statements.rb:7:in `select\_all’  
/home/francois/src/xlsuite.org/vendor/rails/activerecord/lib/active\_record/base.rb:427:in  
`find_by_sql' /home/francois/src/xlsuite.org/vendor/rails/activerecord/lib/active_record/base.rb:997:in `find\_every’  
/home/francois/src/xlsuite.org/vendor/rails/activerecord/lib/active\_record/base.rb:991:in  
`find_initial' /home/francois/src/xlsuite.org/vendor/rails/activerecord/lib/active_record/base.rb:417:in `find’

It translates to “The Party column does not exist”. I ran the  
statement in psql, and sure enough, I get the same error. If I quote  
the routable\_type column’s value using single-quotes, I get the  
expected results.

My models look like this:

class Party \< AR::B  
has\_many :contact\_routes, :as =\> :routable  
end

class ContactRoute \< AR::B  
acts\_as\_list  
belongs\_to :routable, :polymorphic =\> true  
end

I’m on the 1.2 stable branch, using Ruby 1.8.4 and PostgreSQL 8.1.

## Thanks !

François Beausoleil  
[http://blog.teksol.info/](http://blog.teksol.info/)  
[http://piston.rubyforge.org/](http://piston.rubyforge.org/)