bgror

Quick Tip: Search for null dates in Thinking Sphinx »

Created at: 17.10.2009 17:35, source: Hackido, tagged: rails thinking-sphinx sphinx

In one of my projects, when a record is deleted I set a deleted_at field with the timestamp rather than actually destroying it. Because that model is indexed by Thinking Sphinx I want to make sure that it doesn't then show up in any search results (the user says she deleted it, right?) I had thought the way to do that would be as simple as passing an extra condition to my query, but I was wrong.


Instead, what you have to do is create an attribute in your model for the datetime field in question and use :with => to filter it down. It might look like this.

  # Search Index.
  define_index do
    indexes :name, :sortable => true
    indexes :description, :sortable => true
    
    has :deleted_at

    set_property :delta => true
  end

Foo.search(params[:search], :with => {:deleted_at => 0})

Quick Tip: Search Email in Thinking Sphinx »

Created at: 06.06.2009 19:24, source: Hackido, tagged: rails thinking-sphinx sphinx

If you use Sphinx as your search backend you may have noticed that it won't search for an entire email address. It's a bit perplexing at first since everything else works so well. After banging my head on the issue for a few hours, I got some direct help from Pat Allan, the creator of Thinking Sphinx. The problem is with the "@" symbol which is a reserved character in Sphinx. To get around that we need to modify Sphinx's allowable character set.

Now for better or for worse, you don't actually need to define any sort of config file by default to use Thinking Sphinx.. it's smart enough to pick sensible defaults. But in this case we'll have to go ahead and create one.


Every Ruby on Rails project comes with a config folder where many files you may need to modify are stored. In this directory create a file called sphinx.yml. It's a YAML file so be careful about spacing here. It's as sensitive as your database.yml file so if you accidentally alter the spacing things may not work.

For our example, let's use the UTF-8 character set. So in that sphinx.yml file, paste this content:

development:
  port: 3312
  charset_table: "0..9, a..z, _, @, A..Z->a..z, U+410..U+42F->U+430..U+44F, U+430..U+44F"
test:
  port: 3313
  charset_table: "0..9, a..z, _, @, A..Z->a..z, U+410..U+42F->U+430..U+44F, U+430..U+44F"
production:
  port: 3312
  charset_table: "0..9, a..z, _, @, A..Z->a..z, U+410..U+42F->U+430..U+44F, U+430..U+44F"

rake thinking_sphinx:rebuild

rake thinking_sphinx:stop
rake thinking_sphinx:index
rake thinking_sphinx:start

Sum and index a related column in Thinking Sphinx »

Created at: 04.06.2009 03:13, source: Hackido, tagged: rails thinking-sphinx sphinx

It's fairly straight forward to get indexing working using the excellent Thinking Sphinx plugin. But sometimes you may want to do something a little more complicated. For example, if you have a Model foo with a has_many relationship to model Bar and you want to search on Bar how do you set it up? Or, what if you want to find out how many Bars Foo has? Enough! Let's work on an example.

Let's start and try to index a User model. That user has many bank accounts each of which has a balance:

User 1
--> Account 1 ($5)
--> Account 2 ($100)
--> Account 3 ($3)

User 2
--> Account 4 ($5)
--> Account 5 ($75)

In our example, we want to search for users by the amount of cash they have in their accounts. To do that we need to configure sphinx to first tell it that a User has many Accounts with a bank balance:

class Brigade < ActiveRecord::Base
  has_many :accounts
  
  #sphinx index
  define index do
    has accounts(:bank_balance), :as => :bank_balance
    indexes "SUM(bank_balance)", :as => :total_bank_balance, :sortable => true
  end
end

Named Scopes and Thinking Sphinx »

Created at: 19.04.2009 01:18, source: Hackido, tagged: rails thinking-sphinx

I'm really not a fan of the Thinking Sphinx conditions syntax. It's different than what I'm used to using in ActiveRecord and has caused me some problems with dates and such. Instead I use named scopes whenever I can. For example, in Railfood, a site for locomotive parts, I use a named scope to show only products that are in stock. That causes some issues, not only because of all the nil records but because the default number of results returned is 20.

Note that this article is no longer that useful. Instead of named scopes please look at sphinx scopes. Article coming soon.


For example:

@p =Product.current.search("injector").size 

=> 20 

@p =Product.current.search("123").size 

=> 20 

[nil, nil, nil, nil nil,nil, nil, nil, nil nil,nil, nil, nil, nil nil,nil, nil, nil, nil nil,]

@p =Product.current.search("injector").compact.size 

=> 0

@p =Product.current.search("injector", :per_page => 20000).compact.size 

=> 1

@p =Product.current.search("injector",
                   :per_page => 20000).paginate(:per_page => 8, :page => params[:page])