Which statement correctly describes when to use Process When Group Changes?

• A. It can be used with any data without pre-sorting.
• B. It must be used only when data is pre-sorted.
• C. It automatically sorts data.
• D. It discards unsorted groups.

Answer: (B)

Process When Group Changes relies on a sequence where all features belonging to the same group appear together. It detects a boundary when the grouping value switches from one group to another. If the input isn’t sorted by the group field, features from the same group can be scattered, so the transformer would see group changes at the wrong times and the processing would be incorrect. It doesn’t sort the data itself, so you must provide input that is pre-sorted by the grouping attribute. It doesn’t discard unsorted groups; it simply won’t operate correctly unless the data are ordered. This is why the statement about needing pre-sorted data best describes how to use this transformer.