This content has been marked as final. Show 2 replies
Listboxes are used to select data. Is there a way to do the opposite: to exclude anything selected from a listbox?
Let's say there's a table containing student IDs and names.
There's another table that links each student to the classes they're taking.
Student ID Course ID
Based on this example, John is taking three classes, Beth is taking one and Zack is taking three.
I wish to have listbox#1 for CourseID which would just show all the courses being taken by students.
The problem is I wish to have listbox#2 showing courseID, but exclude anything selected from listbox#2 from the current selection.
That means if I select Math 101 from listbox #1, my selection should include all 3 students.
But if I select Art232 and Chem101 from listbox#2, I want my current selection to exclude John and Zack.
This would help in finding this: "Show me students that are currently taking Math 101, who are not taking either one of Art232 or Chem 101."
I want the user to be able to first choose Math101, and also have the option to choose Art232 and Chem101 from a separate listbox so they can get excluded.
Is there a way to do this?
Perhaps even by using some expressions in charts so that it'll exclude students who are taking courses selected from the 'exclude' list?
Maybe by set analysis?
I find the challenge in the multi-link relationship between student and courses.