In Access 2.0 there is an Eval() function which will automatically evaluate numeric expressions. This functionality does not appear to exist in VB 4. I found an article in the MS Knowledge base (Q86688) which leads me to believe that the functionality was intentionally left out. The goal is to be able to store user-defined functions in a table and fire them based on user input. Is this possible and if so, how.
Function pointers, essentially what you are describing, are not supported under Visual Basic. You can’t store a procedure name in the database and tell Visual Basic to dynamically run it. However, you could create a procedure that interpreted a code from the database and then run a particular piece of code based on that code. That’s about as close as you can get. You could also make separate executables for each different piece of code you might want to run, but that’s even worse and more complicated.