1 files changed, 12 insertions, 10 deletions

diff --git a/activerecord/lib/active_record/calculations.rb b/activerecord/lib/active_record/calculations.rb
index 3c5caefe3b..10e8330d1c 100644
--- a/activerecord/lib/active_record/calculations.rb
+++ b/activerecord/lib/active_record/calculations.rb
@@ -46,28 +46,28 @@ module ActiveRecord
         calculate(:count, *construct_count_options_from_args(*args))
       end
 
-      # Calculates the average value on a given column.  The value is returned as a float.  See #calculate for examples with options.
+      # Calculates the average value on a given column.  The value is returned as a float.  See +calculate+ for examples with options.
       #
       #   Person.average('age')
       def average(column_name, options = {})
         calculate(:avg, column_name, options)
       end
 
-      # Calculates the minimum value on a given column.  The value is returned with the same data type of the column.  See #calculate for examples with options.
+      # Calculates the minimum value on a given column.  The value is returned with the same data type of the column.  See +calculate+ for examples with options.
       #
       #   Person.minimum('age')
       def minimum(column_name, options = {})
         calculate(:min, column_name, options)
       end
 
-      # Calculates the maximum value on a given column.  The value is returned with the same data type of the column.  See #calculate for examples with options.
+      # Calculates the maximum value on a given column.  The value is returned with the same data type of the column.  See +calculate+ for examples with options.
       #
       #   Person.maximum('age')
       def maximum(column_name, options = {})
         calculate(:max, column_name, options)
       end
 
-      # Calculates the sum of values on a given column.  The value is returned with the same data type of the column.  See #calculate for examples with options.
+      # Calculates the sum of values on a given column.  The value is returned with the same data type of the column.  See +calculate+ for examples with options.
       #
       #   Person.sum('age')
       def sum(column_name, options = {})
@@ -245,12 +245,14 @@ module ActiveRecord
           options.assert_valid_keys(CALCULATIONS_OPTIONS)
         end
 
-        # Converts a given key to the value that the database adapter returns as
-        # a usable column name.
-        #   users.id #=> users_id
-        #   sum(id) #=> sum_id
-        #   count(distinct users.id) #=> count_distinct_users_id
-        #   count(*) #=> count_all
+        # Converts the given keys to the value that the database adapter returns as
+        # a usable column name:
+        #
+        #   column_alias_for("users.id")                 # => "users_id"
+        #   column_alias_for("sum(id)")                  # => "sum_id"
+        #   column_alias_for("count(distinct users.id)") # => "count_distinct_users_id"
+        #   column_alias_for("count(*)")                 # => "count_all"
+        #   column_alias_for("count", "id")              # => "count_id"
         def column_alias_for(*keys)
           connection.table_alias_for(keys.join(' ').downcase.gsub(/\*/, 'all').gsub(/\W+/, ' ').strip.gsub(/ +/, '_'))
         end