Merge branch 'master' of https://github.com/denysonique/kaminari into denysonique-master

lib/kaminari/models/active_record_relation_methods.rb

@@ -12,10 +12,18 @@ module Kaminari
       # #count overrides the #select which could include generated columns referenced in #order, so skip #order here, where it's irrelevant to the result anyway
       @total_count ||= begin
         c = except(:offset, :limit, :order)
+        
         # a workaround for 3.1.beta1 bug. see: https://github.com/rails/rails/issues/406
         c = c.reorder nil
+        
         # Remove includes only if they are irrelevant
         c = c.except(:includes) unless references_eager_loaded_tables?
+        
+        uses_distinct_sql_statement = c.to_sql =~ /DISTINCT/i
+        if uses_distinct_sql_statement
+          return c.length
+        end
+          
         # .group returns an OrderdHash that responds to #count
         c = c.count
         c.respond_to?(:count) ? c.count : c