Ways to show only the non-end dated portofolio manager.

Question

Hi All,
I have a fund raising application (Raiser's edge), and I have to show each donor along with his/her primary portfolio manager.  Each donor could have more than one manager but there could be only two current manager (primary & secondary).  If the portfolio manager is neither primary nor secondary, we end-date them.  So I tried to create a formula to show only Current Primary Manager, but was unable to:
IF  ( ISNULL({GfCnRelSol_1.GfCnRelSol_1_Date_To}) or
      ({GfCnRelSol_1.GfCnRelSol_1_Date_To} = ""))
and
       ({GfCnRelSol_1.GfCnRelSol_1_Solicitor_Type} = "Foundation Primary") then
        {GfCnRelSol_1.GfCnRelSol_1_Name}
else
This formula will show each donor with their primary manager whether it is an old/end-dated or not. 
I also set the Convert Database Null Value to Default
***The Date To is considered "String" data type as opposed to Date Data Type.

Answer 1

I thought that is what you wanted it to do.
All that formula is doing is filtering records based on
{GfCnRelSol_1.GfCnRelSol_1_Solicitor_Type} = "Foundation Primary"
and
{GfCnRelSol_1.GfCnRelSol_1_Date_To} being blank
That means it will only find donors that that have an account manager listed as "Foundation Primary" AND that has no Date_To value.
If that is not what you are wanting just let me know.
Jason