The AttributeCopier and AttributeRenamer transformers can set an attribute value, but only where the attribute doesn't already exist.

• A. True
• B. False
• C. Sometimes
• D. Not sure

Answer: (A)

The idea being tested is how these transformers handle setting values when an attribute already exists. Both AttributeCopier and AttributeRenamer are designed to avoid overwriting existing data on a feature. An AttributeCopier copies the value from a source attribute into a destination attribute, but it only creates that destination attribute if it doesn’t already exist; if the destination attribute is already present, its value is left unchanged. Similarly, AttributeRenamer changes the name of an attribute (giving the existing value a new key) and will not overwrite an attribute that already has the target name; if a naming collision would occur, the operation is typically prevented or warned, preserving the existing attribute.

So, you can end up setting a new attribute value only when that attribute doesn’t already exist, making the statement true.