Which statement represents an example of conditional filtering?

• A. Adding an attribute with a value set to the current date
• B. Setting a reader parameter to overwrite the destination database when the workspace runs
• C. Writing all data to multiple formats
• D. Only writing data that passes validation tests

Answer: (D)

Conditional filtering means testing each feature and only letting through those that meet the test. Writing only data that passes validation tests is a direct example: every feature is checked against validation rules, and only those that satisfy the rules are written downstream. Features that fail the validation are blocked or sent to a separate path, ensuring the output contains only valid data. This is typically implemented in FME with a Tester or AttributeFilter, which evaluates a boolean condition for each feature and routes the passing features to the next step. The other options involve enhancing data, controlling how writing is performed, or duplicating outputs, none of which rely on selecting features based on a condition.