document: Metaschemas for ER , ORM and UML data models : a comparison This paper provides metaschemas for some of the main database modeling notations used in industry . Two Entity Relationship -LRB- ER -RRB- notations -LRB- Information Engineering and Barker -RRB- are examined in detail , as well as Object Role Modeling -LRB- ORM -RRB- conceptual schema diagrams . The discussion of optionality , cardinality and multiplicity is widened to include Unified Modeling Language -LRB- UML -RRB- class diagrams . Issues addressed in the metamodel analysis include the normalization impact of non-derived constraints on derived associations , the influence of orthogonality on language transparency , and trade-offs between simplicity and expressibility . To facilitate comparison , the same modeling notation is used to display each metaschema . For this purpose , ORM is used because of its greater expressibility and clarity
doc_bio_tags: B O O O B O B B I O O O O O O B O O O O O B I I O O O O O O O O O O O O B I O O O O O O O O O O O B I I O B O B I I O O O O B O B O B O O O O B I I O B O B I O O O O O O O O O B O O O O O O O O O O O B O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O
extractive_keyphrases: metaschemas data models uml database modeling notations information engineering object role modeling conceptual schema diagrams optionality cardinality multiplicity unified modeling language class diagrams normalization orthogonality language transparency orm
abstractive_keyphrases: entity relationship modeling barker notation