A simplied universal relation assumption and its properties
ACM Transactions on Database Systems (TODS)
Tree queries: a simple class of relational queries
ACM Transactions on Database Systems (TODS)
Testing implications of data dependencies
ACM Transactions on Database Systems (TODS)
Multivalued dependencies and a new normal form for relational databases
ACM Transactions on Database Systems (TODS)
Testing satisfaction of functional dependencies
Journal of the ACM (JACM)
Horn clauses and database dependencies
Journal of the ACM (JACM)
Principles of Database Systems
Principles of Database Systems
Can we use the universal instance assumption without using nulls?
SIGMOD '81 Proceedings of the 1981 ACM SIGMOD international conference on Management of data
Independent and separable database schemes
PODS '83 Proceedings of the 2nd ACM SIGACT-SIGMOD symposium on Principles of database systems
Testing containment of conjunctive queries under functional and inclusion dependencies
PODS '82 Proceedings of the 1st ACM SIGACT-SIGMOD symposium on Principles of database systems
Inclusion dependencies and their interaction with functional dependencies
PODS '82 Proceedings of the 1st ACM SIGACT-SIGMOD symposium on Principles of database systems
PODS '82 Proceedings of the 1st ACM SIGACT-SIGMOD symposium on Principles of database systems
Properties of acyclic database schemes
STOC '81 Proceedings of the thirteenth annual ACM symposium on Theory of computing
A formal treatment of imperfect information in database management
A formal treatment of imperfect information in database management
Satisfying database states
The equivalence of solving queries and producing tree projections (extended abstract)
PODS '86 Proceedings of the fifth ACM SIGACT-SIGMOD symposium on Principles of database systems
Sagiv,Y-On finite FD-acyclicity
PODS '86 Proceedings of the fifth ACM SIGACT-SIGMOD symposium on Principles of database systems
Equational theories and database constraints
STOC '85 Proceedings of the seventeenth annual ACM symposium on Theory of computing
Polynomial-time implication problems for unary inclusion dependencies
Journal of the ACM (JACM)
Solving queries by tree projections
ACM Transactions on Database Systems (TODS)
On the recognition and design of acyclic databases
PODS '84 Proceedings of the 3rd ACM SIGACT-SIGMOD symposium on Principles of database systems
Properties of database schemata with functional dependencies
PODS '84 Proceedings of the 3rd ACM SIGACT-SIGMOD symposium on Principles of database systems
Functional and inclusion dependencies a graph theoretic approach
PODS '84 Proceedings of the 3rd ACM SIGACT-SIGMOD symposium on Principles of database systems
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We study how functional dependencies affect the cyclicity of a database scheme; in particular, when does a set of functional dependencies make a cyclic database scheme behave like an acyclic one.A database scheme is fd-acyclic if every pairwise-consistent database state that satisfies the fd's is join-consistent. We give a simple characterization of fd-acyclicity over a restricted class of database schemes. We then give a tableau-based characterization for the general case that leads to an algorithm for testing fd-acyclicity. This algorithm actually solves the more general problem of query equivalence under functional dependencies and typed inclusion dependencies.