Question

I’m still having trouble searching for technologies that are stored in a separate table, where there is a relationship between the technology table (technol) and Project table through a table called projecttechnol.

This is my log when I try to search for a project with a technology (tech1).

Parameters: {"utf8"=>"✓", "client"=>"", "industry"=>"", "role"=>"", "technols"=>{"id"=>["", "1", ""]}, "business_div"=>"", "project_owner"=>"",  "start_date_dd"=>"", "start_date_A"=>"", "start_date_B"=>"", "status"=>"", "keywords"=>"", "per_page"=>"10"}
  User Load (0.6ms)  SELECT "users".* FROM "users" WHERE "users"."id" = 1 LIMIT 1
  Technol Load (0.3ms)  SELECT "technols".* FROM "technols" 
  Project Load (0.5ms)  SELECT "projects".* FROM "projects" ORDER BY client
  Project Load (0.6ms)  SELECT "projects".* FROM "projects" ORDER BY industry
  Project Load (0.4ms)  SELECT "projects".* FROM "projects" ORDER BY role
  Project Load (0.4ms)  SELECT "projects".* FROM "projects" ORDER BY tech
  CACHE (0.0ms)  SELECT "projects".* FROM "projects" ORDER BY tech
  CACHE (0.0ms)  SELECT "projects".* FROM "projects" ORDER BY tech
  CACHE (0.0ms)  SELECT "projects".* FROM "projects" ORDER BY tech
  CACHE (0.0ms)  SELECT "projects".* FROM "projects" ORDER BY tech
  CACHE (0.0ms)  SELECT "projects".* FROM "projects" ORDER BY tech
  Project Load (0.6ms)  SELECT "projects".* FROM "projects" ORDER BY business_div
  Project Load (0.5ms)  SELECT "projects".* FROM "projects" ORDER BY project_owner
  Project Load (0.7ms)  SELECT "projects".* FROM "projects" ORDER BY status
   (0.9ms)  SELECT COUNT(*) FROM "projects" INNER JOIN "projecttechnols" ON "projecttechnols"."project_id" = "projects"."id" INNER JOIN "technols" ON "technols"."id" = "projecttechnols"."technol_id" WHERE "technols"."id" IS NULL

Here is my project.rb:

class Project < ActiveRecord::Base
      attr_accessible :edited_first_name, :edited_last_name, :first_name, :last_name, :business_div, :client, :customer_benifits, :edited_date, :end_date, :entry_date,  :financials, :industry, :keywords, :lessons_learned, :project_name, :project_owner, :role, :start_date, :status, :summary, :tech_id

    validates_presence_of :business_div, :client, :customer_benifits, :end_date,  :financials, :industry, :keywords, :lessons_learned, :project_name, :project_owner, :role, :start_date, :status, :summary#, :tech



    has_many :projecttechnols
    has_many :technols, :through => :projecttechnols


    def self.like(text); "%#{text}%"; end

      def self.search(search_client, search_industry, search_role, search_tech_id, search_business_div, search_project_owner, search_status, search_start_date_dd, search_start_date_A, search_start_date_B,  search_keywords)
        # start with a scoped query, to apply more scopes on it afterwards
        _projects = Project.scoped 
        # then, for each of the parameters, apply the scope only if present
        if search_client.present?
          _projects = _projects.where ['client LIKE ?', like(search_client)] 
        end
        if search_industry.present?
          _projects = _projects.where ['industry LIKE ?', like(search_industry)]
        end
        if search_role.present?
          _projects = _projects.where ['role LIKE ?', like(search_role)]
        end


       _projects = _projects.joins(:technols).
              where("technols.id" => search_techs_ids)

        if search_business_div.present?
          _projects = _projects.where ['business_div LIKE ?', like(search_business_div)]
        end
        if search_project_owner.present?
          _projects = _projects.where ['project_owner LIKE ?', like(search_project_owner)]
        end

         if search_status.present?
          _projects = _projects.where ['status LIKE ?', like(search_status)]
        end



    todays_date = DateTime.now.to_date

    if !search_start_date_A.blank? or !search_start_date_B.blank?
        search_start_date_A = Date.parse(search_start_date_A).strftime("%Y-%m-%d")
        search_start_date_B = Date.parse(search_start_date_B).strftime("%Y-%m-%d")
        todays_date = nil
        search_start_date_dd = nil

        end

    if search_start_date_dd.blank?
        todays_date = nil
    end


    if search_start_date_A.present? or search_start_date_B.present?

          _projects = _projects.where [' DATE(start_date) BETWEEN ? AND ?', search_start_date_A, search_start_date_B]
        end


                    if search_start_date_dd.present?
          _projects = _projects.where ['DATE(start_date) BETWEEN ? AND ?', search_start_date_dd, todays_date]
        end




        if search_keywords.present?
          _projects = _projects.where ['keywords LIKE ?', like(search_keywords)]
        end
        # now you have applied only the present scopes. return the result, and watch 
        # the query as it executes.
        _projects
      end


    def self.paginated_for_index(projects_per_page, current_page)
        paginate(:per_page => projects_per_page, :page => current_page)
      end

    end

Technol.rb:

class Technol < ActiveRecord::Base
  attr_accessible :tech

has_many :projecttechnols
has_many :projects, :through => :projecttechnols
end

Projecttechnol.rb

class Projecttechnol < ActiveRecord::Base
  attr_accessible :project_id, :technol_id

belongs_to :technol
belongs_to :project
end

Can anyone see a solution to this work properly. I am new to rails, so please remember this when attempting to help me. Searching for anything in the technology field returns nothing. Thanks a lot

Answer 1

It looks like you’ve got a typo here in your search parameters:

  def self.search(search_client, search_industry, search_role, search_tech_id...

But yet you use search_techs_id here:

  _projects = _projects.joins(:technols).where("technols.id" => search_techs_ids)

If you examine your queries you can see that its trying to join the two tables with a NULL.

On another note, your search query is a bit long and tough to read, may I suggest using something like this:

class Project < ActiveRecord::Base
  attr_accessible :edited_first_name, :edited_last_name, :first_name, :last_name, 
    :business_div, :client, :customer_benifits, :edited_date, :end_date, :entry_date,  
    :financials, :industry, :keywords, :lessons_learned, :project_name, :project_owner, 
    :role, :start_date, :status, :summary, :tech_id

  validates_presence_of :business_div, :client, :customer_benifits, :end_date,  
   :financials, :industry, :keywords, :lessons_learned, :project_name, :project_owner, 
   :role, :start_date, :status, :summary#, :tech

  has_many :projecttechnols
  has_many :technols, :through => :projecttechnols

  scope :client, { |client| where ['client LIKE ?', like(client) ] }
  scope :industry, { |industry| where ['industry LIKE ?', like(industry)] }
  scope :role, { |role| where ['role LIKE ?', like(search_role)] }
  scope :technologies, { |technology_ids| joins(:technols).where("technols.id}" => technology_ids) }
  scope :division, { |division| where ['business_div LIKE ?', like(search_business_div)] }
  scope :owner, { |owner| where ['project_owner LIKE ?', like(search_project_owner)] }
  scope :status, { |status| where ['status LIKE ?', like(search_status)] }
  scope :keywords, { |keywords| where ['keywords LIKE ?', like(keywords)] }
  scope :started_before, { |date| where ['start_date <= ?',date] }
  scope :started_after, { |date| where ['start_date >= ?',date] }

  def self.search_fields    
    [:client,:industry,:role,:technologies,:division,:owner,:status,:started_before,:started_after,:keywords]
  end

  def self.search(params)
    search_fields.inject(scoped) do |scopes,key|
      params[key].present? ? scopes.send(key,params[key]) : scopes
    end
  end

  def self.like(text); "%#{text}%"; end

  def self.paginated_for_index(projects_per_page, current_page)
    paginate(:per_page => projects_per_page, :page => current_page)
  end

end

This way, your search method is quite a bit shorter, and since you’ve broken out all these parameters into their own scopes, if you need to reuse them, method is already there.

Hope this helps.