Comparison Failed expecting empty string on nullable int versus NULL value

This is actually SoapUI NG.

I am connecting to a Microsoft sql server database to gather data for my source. As you can see from the result of my query (datasource I am using), you can see I return an empty string.

Results of Query

 However, when I run the test case and apply my assertion, it is failing because it says the actual value is NULL, which you can see it is not.

Is there a schema or something I need to set up so it knows how to read nulls vs. empty strings?