I am not sure what you mean by this.
Let’s back up a bit. I assume your intention is to select a “Project” in one view and then through an interactive dashboard display in a second view a distinct list of “Items” from your “Items” table that belong to that project. Do I have that correct?
To do this, two things need to happen:
1). You need to have the Project Key column represented on your “Items” table so the proper filtering can take place. I believe you can add this as a Virtual Column.
2). You will need to provide a list of “Items” to the “Items” view that are already reduced to distinct items by Project. Probably the easiest way to do this is to create a Slice to reduce the rows…although a solution is not coming to mind right away. I’m sure there’s a way to do it.