Re: The system has attempted to use an undefined value, which usually indicates a programming error, either in your code or

["BKBK"]

I didn't want to weigh array of structs versus queries, in general. There is no 
point. They have their pros and cons. Hence what you say makes sense. However, 
in the context of passing complex data to a function, which is the case here, a 
query or 2-D array would be more appropriate.