Document other options available to migration's add_column. #6419

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@5333 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

activerecord/CHANGELOG

 *SVN*
 
+* Document other options available to migration's add_column. #6419 [grg]
+
 * MySQL: all_hashes compatibility with old MysqlRes class.  #6429 [Jeremy Kemper]
 
 * Fix has_many :through to add the appropriate conditions when going through an association using STI. Closes #5783. [Jonathan Viney]

activerecord/lib/active_record/migration.rb

@@ -66,7 +66,8 @@ def initialize(version)
   #   named +column_name+ specified to be one of the following types:
   #   :string, :text, :integer, :float, :decimal, :datetime, :timestamp, :time,
   #   :date, :binary, :boolean. A default value can be specified by passing an
-  #   +options+ hash like { :default => 11 }.
+  #   +options+ hash like { :default => 11 }. Other options include :limit and :null (e.g. { :limit => 50, :null => false })
+  #   -- see ActiveRecord::ConnectionAdapters::TableDefinition#column for details.
   # * <tt>rename_column(table_name, column_name, new_column_name)</tt>: Renames a column but keeps the type and content.
   # * <tt>change_column(table_name, column_name, type, options)</tt>:  Changes the column to a different type using the same
   #   parameters as add_column.