sql - Iterating through two listbox in Access VBA

Question

I have a form with a text input and two multiselect list boxes. I am using the selected items in the list boxes as parameters in a query. List box one is Year and and two is Item. I need to iterate through both list boxes to get the results for each item in each year.

Example:

For Each y in years
    For Each i in items
         run query with these parameters
    next i '
next y

The text input is required and not an issue. The thing is, both list boxes are optional. If no year is selected, I need all years. The same for items. Not having any item selected in either/both list boxes is where I am having trouble.

Answer 1

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