Update README.markdown

README.markdown

@@ -80,7 +80,8 @@ Changelog
 * `where_id_in()` for selecting multiple records by primary key [[lrlopez](https://github.com/lrlopez)] - [issue #202](https://github.com/j4mie/idiorm/issues/202)
 * Add compound primary key support [[lrlopez](https://github.com/lrlopez)] - [issue #171](https://github.com/j4mie/idiorm/issues/171)
 * Add a RAW JOIN source to the query [[moiseevigor](https://github.com/moiseevigor)] - [issue #163](https://github.com/j4mie/idiorm/issues/163)
-* offsetExists() should return true for null values, resolves [#181](https://github.com/j4mie/idiorm/issues/163) [[cainmi](https://github.com/cainmi)] - [issue #214](https://github.com/j4mie/idiorm/pull/214)
+* offsetExists() should return true for null values, resolves [#181](https://github.com/j4mie/idiorm/issues/181) [[cainmi](https://github.com/cainmi)] - [issue #214](https://github.com/j4mie/idiorm/pull/214)
+* Restrict null primary keys on update/delete, resolves [#203](https://github.com/j4mie/idiorm/issues/203) [[cainmi](https://github.com/cainmi)] - [issue #205](https://github.com/j4mie/idiorm/issues/205) 
 * Ensure parameters treated by type correctly [[charsleysa](https://github.com/charsleysa)] & [[SneakyBobito](https://github.com/SneakyBobito)] - [issue #206](https://github.com/j4mie/idiorm/issues/206) & [issue #208](https://github.com/j4mie/idiorm/issues/208)
 * Reduce the type casting on aggregate functions to allow characters [[herroffizier](https://github.com/herroffizier)] - [issue #150](https://github.com/j4mie/idiorm/issues/150)
 * Prevent invalid method calls from triggering infinite recursion [[michaelward82](https://github.com/michaelward82)] - [issue #152](https://github.com/j4mie/idiorm/issues/152)