When transforming relational database (RDB) schema into object-oriented dat
abase(OODB) schema, much effort was put on examining key and inclusion depe
ndency (ID) constraints to identify class and establish inheritance and ass
ociation between classes. However, in order to further remove the original
data redundancy and update anomaly, multi-valued dependency (MVD) should al
so be examined. In this paper, we discuss class structures and define well-
structured classes. Based on MVDs, a theorem is given transforming a relati
on schema into a well-structured class. To transform. RDB schema into OODB
schema, a composition process simplifying the input RDB schema and an algor
ithm transforming the simplified RDB schema into well-structured OODB class
es are developed. (C) 1999 Elsevier Science B.V. All rights reserved.