XML Constraint-tree-based Functional Dependencies

Abstract

A concept of functional dependency in XML documents based on constraint-tree is proposed. The definition proposed in our paper overcomes the shortcomings of previous definitions in the following aspects: (1) it captures the tree-structured characteristics of XML documents in structure; (2) it considers a more general situation of XML functional dependencies based on sub-trees with some constraint conditions in XML documents. The relationship between our definition of XML functional dependencies and other related definitions is also discussed in the paper