About Right-Exclusive Join
Right-Exclusive Join returns the items present in List B but not in List A — the set difference B − A. It is the mirror of Left-Exclusive Join: instead of asking what is in A and missing from B, this tool asks what is in B and missing from A. The output preserves the order from List B.
The distinction matters because most real workflows have an obvious baseline list and a new list. If you treat the baseline as A and the new data as B, then Right-Exclusive Join is what you need to find newly-added items: new customers added since the last export, new dependencies introduced in a feature branch, accounts that appeared in this morning's snapshot but not yesterday's. Having both directions as separate tools means you do not have to mentally swap inputs to flip the question — open the tool that matches the question you are asking.
Examples
List A:
apple
banana
cherry
date
List B:
cherry
date
elderberry
figelderberry
figItems present in B but missing from A. To find items only in A, use Left-Exclusive Join.
Frequently asked questions
Is this the same as Left-Exclusive with the lists swapped?
Mathematically yes — B − A (Right-Exclusive) is identical to running Left-Exclusive with A and B swapped. We expose both so you can keep `baseline = A, new = B` consistent across many comparisons, which is less error-prone than swapping inputs each time.
What if a value appears multiple times in B?
Duplicates inside B are collapsed; each unique value not present in A appears once in the output.
When should I use this versus Full-Exclusive?
Use Right-Exclusive when you only care about additions to B (the new side). Use Full-Exclusive when you need both additions and removals — items unique to either side — in a single output.
Does the output order match List B?
Yes. The output follows the first occurrence of each remaining item in List B.