Many parts of a Systems Engineering (SE) process involving linking two or more sets of items together. This creates a need to display this linkage, from the perspective of both sets of items. There are several options for displaying this linkage information, one is as a nested table. If we have two sets of items linked together, A and B:

then we will have items from set A linked to zero or more items from set B:

and in a nested table we show the linked items from set B next to their corresponding item from set A. The linked items are usually shown to the right:

but they can be shown to the left:

or the linked items can be shown below the items from set A:

or they can be shown above the items from set A:

depending how we define the view that creates the nested table.

In a nested table, we use views to specify how each of the sets of items are to be shown. So when there are two sets of items, A and B, we will need two views:

• A view that describes how the items from set A are to be shown
• A view that describes how the linked items from set B are to be shown

We can think of these views as being nested, or being used within each other, rather like the pieces in a Russian doll. When we create a nested table, we start at the innermost view, the view for the items in set B in this case, and then reference this view from the next outermost view, in this case from the view for the items in set A. We repeat this process until we reach the view for the initial set of items.

As we only have two sets of items in this example, we only have two views, and so our process will be:

• Define a view for the items in set B that shows the attributes that we want to see (in a real project a suitable view may already exist)
• Define a view for the items in set A that shows the attributes that we want to see and add a view cell to this view that references the linked items from set

1. 3SL Newsletters
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3. Need Help?
4. NASA Cradle User Symposium
5. REConf 08 Conference
6. Change to New Item Function
7. Nested Tables
8. How to Create Nested Tables
9. How to Create Multiple Row Views
10. Regular Expressions
11. Regular Expressions in Queries
12. US Price Increase
13. HP-UX Support
14. Old Versions of Cradle

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