Question

Im trying to build advanced search finder for my Candidate model.
Lets imagine it has couple fields + multiple associations like has_many: languages & has_many: skills. Now I’m building query like this:

query = Candidate.select("*")
if position_name
  query = query.where('position_name LIKE ? OR position_name IS NULL',"%#{position_name}%")
end 

if salary
  query = query.where('salary <= ? OR salary IS NULL',salary)
end

and so on…

Now I want to add more advanced conditions like to find users who only have such skills like PHP and Java (so return only those users who have both skills)

This works but only when I insert OR

  query = query.joins(:skills)
  query = query.where('`skills`.`name` = ? OR `skills`.`name` = ?',"Java","PHP")

Additionally I’d like the same also for languages (plus, language have language.name & language.level)

Can someone points me in which direction to look? And also how to build such condition where I can multiple skills or multiple languages?

Answer 1

Have a look at the various search gems like Ransack, Metawhere or Searchlogic

http://rubygems.org/gems/ransack

https://github.com/railsdog/searchlogic

Both Ransack and Searchlogic allow searching on associated models and you can use scopes to restrict the search parameters.

Example Search params for Searchlogic.

[search][admitted_gte]  

[search][admitted_lte]  

[search][aetiology_like_any][]  VIRUS

[search][at_risk_gte]   

[search][at_risk_lte]   

[search][died_gte]  

[search][died_lte]  

[search][gezi_reference_like]   

[search][id]    

[search][incidents_location_encrypted_postcode_like]    

[search][lab_confirmed_gte] 

[search][lab_confirmed_lte] 

[search][onset_first_after] 

[search][onset_first_before]    

[search][onset_last_after]  

[search][onset_last_before] 

[search][outbreak_type_equals_any][]    FOODBORNE

[search][point_source_date_after]   

[search][point_source_date_before]  

[search][total_affected_gte]    

[search][total_affected_lte]    

[search][user_reference_like]   

[search][year_equals_any][] 2010

search[order]   descend_by_id

Outbreak_Controller.rb Index action returns the results of the Search query. From 17 Search params only a single searchlogic call is required @search = Outbreak.search(params[:search]). The params are whitelisted against a list of allowed search params – code not shown.

def index

          #set the default index order to be descending Outbreak id
          if !params[:search][:order]
              params[:search][:order] = "descend_by_id"  
          end
          if params[:search][:bacterial_agents_bacterium_name_like_any] != nil && !params[:search][:bacterial_agents_bacterium_name_like_any].empty?
              params[:search][:bacterial_agents_category_like] = "CAUSATIVE"
          end
          if params[:search][:viral_agents_virus_name_like_any] != nil && !params[:search][:viral_agents_virus_name_like_any].empty?
              params[:search][:viral_agents_category_like] = "CAUSATIVE"
          end
          if params[:search][:protozoal_agents_protozoa_name_like_any] != nil && !params[:search][:protozoal_agents_protozoa_name_like_any].empty?
              params[:search][:protozoal_agents_category_like] = "CAUSATIVE"
          end
          if params[:search][:toxic_agents_toxin_name_like_any] != nil && !params[:search][:toxic_agents_toxin_name_like_any].empty?
              params[:search][:toxic_agents_category_like] = "CAUSATIVE"
          end
  #Outbreak.search takes all of the given params and runs it against the Outbreak model and it's associated models
  @search = Outbreak.search(params[:search])
end