Querying incomplete data over extended ER schemata
نویسندگان
چکیده
منابع مشابه
Querying incomplete data over extended ER schemata
Since Chen’s Entity-Relationship (ER) model, conceptual modeling has been playing a fundamental role in relational data design. In this paper we consider an extended ER (EER) model enriched with cardinality constraints, disjointness assertions, and is-a relations among both entities and relationships. In this setting, we consider the case of incomplete data, which is likely to occur, for instan...
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ژورنال
عنوان ژورنال: Theory and Practice of Logic Programming
سال: 2010
ISSN: 1471-0684,1475-3081
DOI: 10.1017/s1471068410000104