Abstract: Based on shared inlining, we present a lossless algorithm to map XML to relations according to XML FDs, which can denote the relative constraints. A new algorithm is proposed to reconstruct the original XML document, using a foreign key join and a path-mapping rule. We show that the normal forms of relations or XML documents after mapping have relations with the mapping algorithm with a normalization degree of original XML DTD or relations. XML normal forms are defined, and propositions and proofs are presented to study the relationship between XML normal forms and the corresponding forms of relations after mapping.

Key words: lossless mapping algorithm, XML normal forms, XML functional dependency