If you’re assigning the values of columns you return from RDO queries into string variables, you’ll get an “Invalid use of Null” error if one of the columns has a Null value. For most purposes, I’d rather have the value as an empty string anyway. Rather than code for that each time I access a column, I’ve written a function called Clean that turns Null values into empty strings. I call it like this:

 strMyString=Clean(rdoResultset("MyVarCharColumn"))

I also convert Empty values as well, for use with Variants:

 Public Function Clean(ByVal varData As Variant) As StringIf IsNull(varData) Then	Clean = ""ElseIf IsEmpty(varData) Then	Clean = ""Else	Clean = CStr(varData)End IfEnd Function