SQL Server 2008修改表出错Saving changes is not permitted的解决方法

今天演示BPM的开发的例子，居然当众出了个小丑，问题就在创建SQL 2008的数据表时，保存后再修改表结构，居然出错：“Saving changes is not permitted. The changes you have made require the following tables to be dropped and re-created. You have either made changes to a table that can’t be re-created or enabled the option Prevent saving changes that require the table to be re-created.”

还好那个字段不要也可以，可以继续下午，但是也浪费了几分钟。

事后经过搜索找到了问题，写在这里给路过的朋友，提个醒。