jhowarth

class SessionsController < Devise::SessionsController
  
  def create
    resource = warden.authenticate!(:scope => resource_name, :recall => :failure)
    return sign_in_and_redirect(resource_name, resource)
  end
  
  def sign_in_and_redirect(resource_or_scope, resource=nil)
    scope = Devise::Mapping.find_scope!(resource_or_scope)
    resource ||= resource_or_scope

scottlowe

class Article < ActiveRecord::Base
  validates :title, :body, :presence => true

  # Note that ActiveRecord ARel from() doesn't appear to accommodate "?"
  # param placeholder, hence the need for manual parameter sanitization
  def self.tsearch_query(search_terms, limit = query_limit)
    words = sanitize(search_terms.scan(/\w+/) * "|")

    Article.from("articles, to_tsquery('pg_catalog.english', #{words}) as q").
      where("tsv @@ q").order("ts_rank_cd(tsv, q) DESC").limit(limit)

hgmnz

Types of index scans

Indexes

Sequential Scan:

• Read every row in the table
• No reading of index. Reading from indexes is also expensive.

peter

-- Order by one indexed column (FAST)
newsdesk_production=# explain analyze select * from pressreleases order by published_at DESC limit 100;
                                                                                   QUERY PLAN                                                                                    
---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 Limit  (cost=0.00..249.91 rows=100 width=1207) (actual time=26.070..716.453 rows=100 loops=1)
   ->  Index Scan Backward using pressreleases_published_at_index on pressreleases  (cost=0.00..964766.62 rows=386042 width=1207) (actual time=26.067..716.343 rows=100 loops=1)
 Total runtime: 716.709 ms
(3 rows)

- Order by two separately indexed columns (SLOW)