O2, an object-oriented data model
SIGMOD '88 Proceedings of the 1988 ACM SIGMOD international conference on Management of data
Functional computations in logic programs
ACM Transactions on Programming Languages and Systems (TOPLAS)
Object identity as a query language primitive
SIGMOD '89 Proceedings of the 1989 ACM SIGMOD international conference on Management of data
Queries and views in an object-oriented data model
Proceedings of the second international workshop on Database programming languages
An object-oriented query algebras
Proceedings of the second international workshop on Database programming languages
A formal approach to object-oriented databases
Data & Knowledge Engineering
Functional dependencies in Horn clause queries
ACM Transactions on Database Systems (TODS)
Algebraic support for complex objects with arrays, identity, and inheritance
SIGMOD '91 Proceedings of the 1991 ACM SIGMOD international conference on Management of data
Reasoning about functional dependencies generalized for semantic data models
ACM Transactions on Database Systems (TODS)
The functional data model and the data languages DAPLEX
ACM Transactions on Database Systems (TODS)
Limitations of record-based information models
ACM Transactions on Database Systems (TODS)
Efficient optimization of a class of relational expressions
ACM Transactions on Database Systems (TODS)
A language facility for designing database-intensive applications
ACM Transactions on Database Systems (TODS)
Reasoning About Equations and Functional Dependencies on Complex Objects
IEEE Transactions on Knowledge and Data Engineering
COL: A Logic-Based Language for Complex Objects
EDBT '88 Proceedings of the International Conference on Extending Database Technology: Advances in Database Technology
The Implication Problem for Data Dependencies
Proceedings of the 8th Colloquium on Automata, Languages and Programming
Functional dependencies in logic programs
VLDB '85 Proceedings of the 11th international conference on Very Large Data Bases - Volume 11
On Decidability and Complexity of Description Logics with Uniqueness Constraints
ICDT '01 Proceedings of the 8th International Conference on Database Theory
On Reasoning about Structural Equality in XML: A Description Logic Approach
ICDT '03 Proceedings of the 9th International Conference on Database Theory
Reasoning about Uniqueness Constraints in Object Relational Databases
IEEE Transactions on Knowledge and Data Engineering
On reasoning about structural equality in XML: a description logic approach
Theoretical Computer Science - Database theory
On Keys and Functional Dependencies as First-Class Citizens in Description Logics
Journal of Automated Reasoning
Efficient reasoning about a robust XML key fragment
ACM Transactions on Database Systems (TODS)
Constraint acquisition for Entity-Relationship models
Data & Knowledge Engineering
Applications and extensions of PTIME description logics with functional constraints
IJCAI'09 Proceedings of the 21st international jont conference on Artifical intelligence
On order dependencies for the semantic web
ER'07 Proceedings of the 26th international conference on Conceptual modeling
On keys and functional dependencies as first-class citizens in description logics
IJCAR'06 Proceedings of the Third international joint conference on Automated Reasoning
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Virtually all semantic or object-oriented data models assume that objects have an identity separate from any of their parts and allow uses to define complex object types in which part values may be any other objects. In G. E. Weddell (ACM Trans. Database Systems17, No. 1 (1992), 32-64), a more general form of functional dependency is proposed for such models in which component attributes may correspond to descriptions of property paths, called path functional dependencies (PFDs). The main contribution of the reference is a sound and complete axiomatization for PFDs when databases may be infinite. However, a number of issues were left open which are resolved in this paper. We first prove that the same axiomatization remains complete if PFDs are permitted empty left-hand sides, but that this is not true if logical consequence is defined with respect to finite databases. We then prove that the implication problem for arbitrary PFDs is decidable. The proof suggests a means of characterizing an important function closure which is then used to derive an effective procedure for constructing a deterministic finite state automaton representing the closure. The procedure is further refined to efficient polynomial time algorithms for the implication problem for cases in which antecedent PFDs are a form of complex key constraint.