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website/content/specification/syntax/constraints.md

@@ -215,7 +215,7 @@ A `<key-field>` assembly of an `<is-unique>` constraint defines the flag or fiel
 
 An `is-unique` constraint MAY define more than one `<key-field>` assembly. The composite key for each entry in the index is the combination of values for the `@target` of every `<key-field/>`. The composite values of the key are the discriminator for the uniqueness of the index entry.
 
-If the evaluation of the Metapath `@target` of the `<key-field>` results in a true result, then `@target` does not occur more than once.
+When evaluating a given key relative to other computed keys for the same constraint, if the given key has the same computed key value as another node matching the same constraint, then the target node MUST be considered to not pass the constraint.
 
 ## Enumerated values