gistfile1.txt

  def has_word?(word)
    matching_words = dictionary_words.where(:word => word.upcase).limit(1)
    if matching_words.blank?
      false
    else
      true
    end
  end


Slow! :(

1.9.3-p429 :069 > Benchmark.measure { d.has_word?('cracks') }
   (0.6ms)  SELECT COUNT(count_column) FROM (SELECT 1 AS count_column FROM "dictionary_words" WHERE "dictionary_words"."dictionary_id" = 1 AND "dictionary_words"."word" = 'CRACKS' LIMIT 1) subquery_for_count 
 =>   0.010000   0.000000   0.010000 (  0.003083)
 


Fast!

1.9.3-p429 :092 > d.dictionary_words.where(:word => 'CRACKS').limit(1)
  DictionaryWord Load (0.5ms)  SELECT "dictionary_words".* FROM "dictionary_words" WHERE "dictionary_words"."dictionary_id" = 1 AND "dictionary_words"."word" = 'CRACKS' LIMIT 1
 => [#<DictionaryWord id: 213357, word: "CRACKS", length: 6, dictionary_id: 1, created_at: "2013-06-24 00:29:00", updated_at: "2013-06-24 00:29:00", seed: 16382530>] 

1.9.3-p429 :098 > b = Benchmark.measure { d.dictionary_words.where(:word => 'CRACKS').limit(1) }
 =>   0.000000   0.000000   0.000000 (  0.000540)