SQL & PL/SQL

Hi

I am having great difficulty to resolve the following error - ORA-06502: PL/SQL: numeric or value error: character string buffer too small . In my Oracle Package, I have a Function that returns a varchar(255).

My Function is basically as follows:

FUNCTION GetUserDept (DeptNum IN NUMBER) RETURN VARCHAR2
IS

deptname varchar(255);

BEGIN

SELECT name INTO deptname
FROM depts
where id = DeptNum;

RETURN deptname
END;

The SQL is running correctly and returns one result, which is what I want. However, when I call the function in my .NET C# code, this is when I am seeing the error message.

In my code, I said that the commandtype is a stored procedure, passed the parameters, and add it to to the parameters, with the return type and direction put first and executed as a scalar. The code executes, and then fails at the ExecuteScalar line, and it is at this point on my exception handler that I see the error message ORA-6502.

This really odd, because I have two other functions that return numbers, and I have executed them in the same way, and theses works!

I have checked my function and can't see what is wrong, and I have tried changing the return type from varchar2 to NVarchar on the return type, but this made no difference.

This problem has really dogged me for hours and I cannot see how to resolve it.

Can someone, please help me?