Jerry, there is no MSSQL adapter for Rails. If you feel strongly enough about this, then you should consider writing one.
What about a real string value "NULL" inputted by end user?
I don't think that is a good solution. IMP, it should be the adapter's matter. That means we should catch it by recognizing the column attributes (type?) and then replace the value.
While googling this issue, I found the "Article":http://thisoldcoder.com/
This fix seems to solve my problem.
Would like to hear comments on this fix?
rails changes nil to null before saving and also for retrieving from database it changes null to nil. I think you might be storing null as a string and this causing an issue for you.