...

worked.

Thank you for the prompt response. Your approach is similar to the one that I had in mind. Here’s how it worked:

app/models/task.rb:

class Task  false, :type => :integer
end

app/views/tasks/index.html.erb

 {:method => :get} do |f| %>

   true}, 0, nil %>

It does sound like I need to use an include (left join) and then just select the unique entries it returns. I’m probably not doing this correctly (couldn’t find much info on using includes in named scopes).

I changed my scope to…


scope :contains_string, lambda {|str| where(:title.matches % "%#{str}%" | :body.matches % "%#{str}%" | :tags => [:name.matches % "%#{str}%"]).includes(:tags)}


which gives me the following error…

undefined method `to_sym’ for #;


scope :contains_string, lambda {|str| where(:title.matches % "%#{str}%" | :body.matches % "%#{str}%" | :tags => [:name.matches % "%#{str}%"]).autojoin}

search_methods :contains_string


which was used in a search method to filter objects in a Post model (that uses acts_as_taggable_on for tagging). Before I could search with a string like “welcome” and it would return any post object that had that string in their title, body or tag, even if the object’s tag_list was empty.

with the new version of meta_where that removes the autojoin method I changed my code to…


scope :contains_string, lambda {|str| where(:title.matches % "%#{str}%" | :body.matches % "%#{str}%" | :tags => [:name.matches % "%#{str}%"]).joins(:tags)}

search_methods :contains_string


Now if i search for that same string it will only respond with Post objects that do not have an empty tag_list. I’m sorry for the long comment, I wasn’t sure if this was a bug or if I have my syntax wrong (I guess I’m approaching this a bit like a newbie since I was using that autojoin method before). Maybe I need to use something like thinking sphinx for a text search like this?

Any help would be greatly appreciated.

Set the value for your “null” checkbox to 0, and then do something like this (warning: completely untested, but this should get you close):

scope :in_any_of_categories, lambda { |category_ids|
  ids = category_ids.compact # drop nils since IN (NULL) is invalid SQL
  include_null = ids.delete(0)
  if include_null && ids.any?
    where("category_id IN (?) OR category_id IS NULL", ids)
  elsif ids.any?
    where("category_id IN (?)", ids)
  elsif include_null
    where("category_id IS NULL")
  else # Somehow we got nothing in the array
    self
  end
}

As you figured out, i want to give the user the possibility to search the tasks which belong to the category or categories that she selects from the list of category check boxes. This works fine, but i want to add one more check box to the list of category check boxes for searching those tasks which are in no category (their category_id is null in the database). The user should be able to check any of the check boxes (the special “No category” one or any other category, in any combination). So the resulting SQL would be something like:
- “…. ( category_id IS NULL OR category_id in (1,7) )” if the user selects the “No category” and categories 1 and 7, or
- “…. category_id in (1,7)” if she selects categories 1 and 7, or
- “…. category_id IS NULL” if the selects just the “No category”

I wasn’t yet able to combine the two conditions – the “category_id IS NULL” and the “category_id in (….)”. Any suggestions?

I am aware of the alternative approach of simply defining the “No category” category in the database and use its specific id as any other category_id instead of using NULL for TASK.CATEGORY_ID. I am trying to explore all possibilities before, though. Is it possible to use meta_search in a scenario like this (mixing IS NULL with other SQL predicates as search criteria for the same database column)?

Keep in mind that unless you are casting your parameters to integers, they won’t technically be equal to the value you are comparing them to in the check box array. What that means is that if you’re intending to make the values the user selects become integers, you need to supply the :type option to search_methods:

search_method :in_any_of_categories, :type => :integer

should do the trick.