Model Independent Assertions for Integration of Heterogeneous Schemas

Abstract. Due to the proliferation of database applications, the integration of ex-isting databases into a distributed or federated system is one of the major chal-lenges in responding to enterprises ' information requirements. Some proposed in-tegration techniques aim at providing database administrators (DBAs) with a view definition language they can use to build the desired integrated schema. These techniques leave to the DBA the responsibility of appropriately restructuring schema elements from existing local schemas and of solving inter-schema conflicts. This paper investigates the assertion-based approach, in which the DB~s action is limited to pointing out corresponding elements in the schemas and to defining the nature of the correspondence in between. This methodology is capable of: en-suring better integration by taking into account additional semantic information (assertions about links); automatically solving structural conflicts; building the in-tegrated schema without requiring conforming of initial schemas; applying inte-gration rules to a variety of data models; and performing view as well as database integration. This paper presents the basic ideas underlying our approach and fo-cuses on resolution of structural conflicts. Keyworfls. Database design and integration, distributed atabases, federated databases, heterogeneous databases, chema integration, conceptual modeling. 1