Key Attribute
Choose the feature that contains the key attribute value.
Detects duplicate features based on the value of a key attribute.
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.
Key Attribute
Choose the feature that contains the key attribute value.
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.
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.
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