search models tagged_with OR title like (with acts_as_taggable_on)

Question

I'm doing a search on a model using a scope. This is being accessed by a search form with the search parameter q. Currently I have the code below which works fine for searches on tags associated with the model. But I would also like to search the title field. If I add to this scope then I will get all results where there is a tag and title matching the search term.

However, I need to return results that match the company_id and category_id, and either/or matching title or tag. I'm stuck with how to add an OR clause to this scope.

  def self.get_all_products(company, category = nil, subcategory = nil, q = nil)
    scope = scoped{}
    scope = scope.where "company_id = ?", company
    scope = scope.where "category_id = ?", category unless category.blank?
    scope = scope.tagged_with(q) unless q.blank?
    scope
  end

I'm using Rails 3.

Answer 1

Ever consider Arel? You can do something like this

t = TableName.arel_table
scope = scope.where(t[:title].eq("BLAH BLAH").or(t[:tag].eq("blah blah")))

or else you can do

scope = scope.where("title = ? OR tag = ", title_value, tag_value)

Answer 2

I could be wrong, but I don't think scopes can help you to construct an or condition. You'll have to hand-write the code to buid your where clause instead. Maybe something like this...

clause = "company_id=?"
qparams = [company]

unless category.blank?
    clause += " or category_id=?"
    qparams <= category
end

scope.where clause, *qparams