Single-table inheritance + Polymorphic association + has_many :through association

[regdog]

I have a complex model design.

Say, the Tag model here uses single-table inheritance for different type of categories. The Tagging model use polymorphic assocation for taggings of different category types as well.

Given the following models:

class Tag < ActiveRecord::Base end

class PostCategory < Tag has_many :taggings, :foreign_key => "tag_id" has_many :posts, :through => :taggings end

class Tagging < ActiveRecord::Base belongs_to :taggable, :polymorphic => true

belongs_to :post, :foreign_key => "taggable_id" belongs_to :post_category, :foreign_key => "tag_id" end

class Post < ActiveRecord::Base has_many :taggings, :as => :taggable has_many :categories, :through => :taggings, :source => :post_category end

I want to find Posts which category name may contain string like "eat". e.g. @search = Post.search({:categories_name_contains=>"eat"})

It will return all the posts or none of the posts in database table, depending on whether the search string is contained in any of post category's name.

Is anything wrong with the way I named the search option or is this a Meta-Search limitation ?

Thanks Meta Search! It's a great gem!

Cameo

[ernie]

Can you supply the SQL that MetaSearch generates? Also, is this Rails 3.0 or 3.1?

Sent from my iPhone

On Sep 4, 2011, at 12:16 AM, regdog reply@reply.github.com wrote:

I have a complex model design.

Say, the Tag model here uses single-table inheritance for different type of categories. The Tagging model use polymorphic assocation for different taggable type of tagging as well.

Given the following models:

class Tag < ActiveRecord::Base end

class PostCategory < Tag has_many :taggings, :foreign_key => "tag_id" has_many :posts, :through => :taggings end

class Tagging < ActiveRecord::Base belongs_to :taggable, :polymorphic => true

belongs_to :post, :foreign_key => "taggable_id" belongs_to :post_category, :foreign_key => "tag_id" end

class Post < ActiveRecord::Base has_many :taggings, :as => :taggable has_many :categories, :through => :taggings, :source => :post_category end

I want to find Posts which category name may contain string like "eat". e.g. @search = Post.search({:categories_name_contains=>"eat"})

It will return all the posts or none of the posts in database table, depending on whether the search string is to be contained in some post category name.

Is anything wrong with the way I named the search option or is this a Meta-Search limitation ?

Thanks Meta Search! It's a great gem!

Cameo

Reply to this email directly or view it on GitHub: https://github.com/ernie/meta_search/issues/59

[regdog]

I am on Rails 3.0 9. The SQL is as following:

SELECT posts.* FROM posts LEFT OUTER JOIN taggings ON posts.id = taggings.taggable_id AND taggings.taggable_type = 'Post' LEFT OUTER JOIN tags ON tags.type = 'PostCategory' WHERE (tags.name LIKE '%eat%')

Thanks for the quick reply! :)

[ernie]

It looks like the id part of the join is being left off -- if you write the join manually:

puts Post.joins(:categories).to_sql

What do you get back? The joins will be inner joins in this case instead of outer joins, but otherwise should be similar.

[regdog]

Yes, I get inner joins like this:

SELECT posts.* FROM posts INNER JOIN taggings ON posts.id = taggings.taggable_id AND taggings.taggable_type = 'Post' INNER JOIN tags ON tags.type = 'PostCategory'

So how to I get the result I want that to find Posts which category name may contain string like "eat"?

[ernie]

If you are getting that from a join on your own, this isn't a MetaSearch bug. Sounds like either a bug in the association code or a bug in your association itself. You can try it again in the app without metasearch loaded at all to verify, of course.

Sent from my iPhone

On Sep 4, 2011, at 10:40 AM, regdog reply@reply.github.com wrote:

Yes, I get inner joins like this:

SELECT posts.* FROM posts INNER JOIN taggings ON posts.id = taggings.taggable_id AND taggings.taggable_type = 'Post' INNER JOIN tags ON tags.type = 'PostCategory'

So how to I get the result I want that to find Posts which category name may contain string like "eat"?

Reply to this email directly or view it on GitHub: https://github.com/ernie/meta_search/issues/59#issuecomment-1991516

[regdog]

Ernie, thanks!

I verified the associations myself. It works fine without any errors. I just cannot figure out where is the problem.