Symptoms
Assume that you use business rules in Master Data Services (MDS) of Microsoft SQL Server 2012 or SQL Server 2014. When a business rule sets an attribute value to blank, it sets the blank value to a NULL value on the database side. In this situation, when another business rule evaluates whether the attribute is blank, it does not equate a NULL value with a blank value.
Resolution
The issue was first fixed in the following cumulative update of SQL Server.
Cumulative Update 2 for SQL Server 2012 SP2 /en-us/help/2983175
Cumulative Update 3 for SQL Server 2014 /en-us/help/2984923
Cumulative Update 11 for SQL Server 2012 SP1 /en-us/help/2975396
Each new cumulative update for SQL Server contains all the hotfixes and all the security fixes that were included with the previous cumulative update. Check out the latest cumulative updates for SQL Server:
Workaround
To work around this issue, append checking condition "OR Attribute is equal to ~NULL~" in the business rule when you evaluate whether an attribute is blank.
Status
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.