Detects duplicate features based on the value of one or more key attributes.
Output Ports
This transformer outputs to the Duplicate port any feature whose key attribute value is the same as one previously encountered. Any feature whose key value has not yet appeared is output via the Unique port.
The first feature with a unique key value is output via the Unique port – and subsequent features that have the same key value are output via the Duplicate port.
Parameters
Key Attributes
Specify one or more attributes to use for the key attribute. If more than one attribute is specified, the collective value of those attributes forms the key.
Input is Ordered
Specifies if the current feature should be compared against all previous features, or if it should only be compared against the feature that is immediately before it. If the input data is ordered so that all duplicates are grouped together, set this value to Yes for increased performance.
Usage Notes
This is a more specific type of operation than that provided by the Matcher, which can match on multiple attributes as well as geometry. For such situations, this transformer is dramatically more efficient than the Matcher.
Editing Transformer Parameters
Using a set of menu options, transformer parameters can be assigned by referencing other elements in the workspace. More advanced functions, such as an advanced editor and an arithmetic editor, are also available in some transformers. To access a menu of these options, click 
beside the applicable parameter. For more information, see Transformer Parameter Menu Options.
Transformer Categories
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