SQL Server Nullable Column

Question

I have a SQL Server table with a few columns of type varchar which are nullable. When an aspx page posts data if the textbox is empty, the database table column is updated to an empty string.

To maintain the null value rather han have it replaced by an empty string, I can either have the logic to change the empty string to System.DBnull in the middle tier c# code or do so in the stored procedure.

Are there other better ways to handle this situation?

Answer 1

you can use a trigger or do it in the proc, you can use the NULLIF function

Example

DECLARE @d VARCHAR(20)
SELECT @d = ''
SELECT NULLIF(@d,'')