Conceptual database design: an Entity-relationship approach
Conceptual database design: an Entity-relationship approach
The entity-relationship model—toward a unified view of data
ACM Transactions on Database Systems (TODS) - Special issue: papers from the international conference on very large data bases: September 22–24, 1975, Framingham, MA
Information modeling and relational databases: from conceptual analysis to logical design
Information modeling and relational databases: from conceptual analysis to logical design
NIAM Information Analysis Method: Theory and Practice
NIAM Information Analysis Method: Theory and Practice
Database Schema Transformation and Optimization
OOER '95 Proceedings of the 14th International Conference on Object-Oriented and Entity-Relationship Modelling
Model Driven Development with NORMA
HICSS '07 Proceedings of the 40th Annual Hawaii International Conference on System Sciences
OTM'05 Proceedings of the 2005 OTM Confederated international conference on On the Move to Meaningful Internet Systems
Modeling slowly changing dimensions in ORM
OTM'11 Proceedings of the 2011th Confederated international conference on On the move to meaningful internet systems
Roles in ORM: a suggested semantics
OTM'11 Proceedings of the 2011th Confederated international conference on On the move to meaningful internet systems
Atomicity and Semantic Normalization
International Journal of Information System Modeling and Design
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This paper proposes extensions to the Object-Role Modeling approach to support schema transformations that eliminate unneeded columns that may arise from standard relational mapping procedures. A "unique where true" variant of the external uniqueness constraint is introduced to allow roles spanned by such constraints to occur in unary fact types. This constraint is exploited to enable graphic portrayal of a new corollary to a schema transformation pattern that occurs in many business domains. An alternative transformation is introduced to optimize the same pattern, and then generalized to cater for more complex cases. The relational mapping algorithm is extended to cater for the new results, with the option of retaining the original patterns for conceptual discussion, with the transforms being applied internally in a preprocessing phase. The procedures are being implemented in NORMA, an open-source tool supporting the ORM 2 version of fact-oriented modeling.