create_table rdoc: suggest :id => false for habtm join tables

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@4606 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

activerecord/CHANGELOG

 *SVN*
 
+* create_table rdoc: suggest :id => false for habtm join tables. [Zed Shaw]
+
 * PostgreSQL: return array fields as strings. #4664 [Robby Russell]
 
 * SQLServer: added tests to ensure all database statements are closed, refactored identity_insert management code to use blocks, removed update/delete rowcount code out of execute and into update/delete, changed insert to go through execute method, removed unused quoting methods, disabled pessimistic locking tests as feature is currently unsupported, fixed RakeFile to load sqlserver specific tests whether running in ado or odbc mode, fixed support for recently added decimal types, added support for limits on integer types. #5670 [Tom Ward]

activerecord/lib/active_record/connection_adapters/abstract/schema_statements.rb

@@ -44,8 +44,8 @@ def columns(table_name, name = nil) end
       #
       # The +options+ hash can include the following keys:
       # [<tt>:id</tt>]
-      #   Set to true or false to add/not add a primary key column
-      #   automatically.  Defaults to true.
+      #   Whether to automatically add a primary key column. Defaults to true.
+      #   Join tables for has_and_belongs_to_many should set :id => false.
       # [<tt>:primary_key</tt>]
       #   The name of the primary key, if one is to be added automatically.
       #   Defaults to +id+.