rails active record - Advanced find

Posted by par on Stack Overflow See other posts from Stack Overflow or by par
Published on 2010-03-27T21:48:07Z Indexed on 2010/03/27 21:53 UTC
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ruby-on-rails

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activerecord

I have the following model setup - a User is interested in projects in many project Categories. Each Project has many categories. Like so:

class User
  has_many :projects
  has_and_belongs_to_many :project_categories

class Project
  belongs_to :user
  has_and_belongs_to_many :project_categories

class ProjectCategory
  has_and_belongs_to_many :projects
  has_and_belongs_to_many :users

Now, I'd like to do a find for projects with any of the catogories that a certain user are interested in, i.e. if a user is interested in project categories A,B,C then I'd like to find projects which are part of one or more of those project categories.

Anyone?

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