Abstraction levels for entity-relationship schemas

Schema abstraction is essential in different phases of the design process. During development, it supports browsing of repositories storing design artifacts, during maintenance, it offers a support to the comprehension of large schemas documenting existing systems. In addition, abstract descriptions of reusable portions of conceptual schemas facilitate their reuse in other applications. Systematic abstraction mechanisms need further investigation. An approach to derive semiautomatically abstractions from ER schemas via schema clustering mainly based on the structure of ER schemas is presented and discussed.