SYSTEM/U: a database system based on the universal relation assumption
ACM Transactions on Database Systems (TODS)
Notions of dependency satisfaction
Journal of the ACM (JACM) - The MIT Press scientific computation series
On the properties and characterization of connection-trap-free schemes
PODS '86 Proceedings of the fifth ACM SIGACT-SIGMOD symposium on Principles of database systems
Independent and separable database schemes
SIAM Journal on Computing
Database states and their tableaux
ACM Transactions on Database Systems (TODS)
On the foundations of the universal relation model
ACM Transactions on Database Systems (TODS)
A simplied universal relation assumption and its properties
ACM Transactions on Database Systems (TODS)
A characterization of globally consistent databases and their correct access paths
ACM Transactions on Database Systems (TODS)
Testing implications of data dependencies
ACM Transactions on Database Systems (TODS)
Equivalences Among Relational Expressions with the Union and Difference Operators
Journal of the ACM (JACM)
Testing satisfaction of functional dependencies
Journal of the ACM (JACM)
Horn clauses and database dependencies
Journal of the ACM (JACM)
On the Desirability of Acyclic Database Schemes
Journal of the ACM (JACM)
Efficient query answering in the representative instance approach
PODS '85 Proceedings of the fourth ACM SIGACT-SIGMOD symposium on Principles of database systems
A relational model of data for large shared data banks
Communications of the ACM
A generalized access path model and its application to a relational data base system
SIGMOD '76 Proceedings of the 1976 ACM SIGMOD international conference on Management of data
An algorithm for servicing multi-relational queries
SIGMOD '77 Proceedings of the 1977 ACM SIGMOD international conference on Management of data
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
PODS '84 Proceedings of the 3rd ACM SIGACT-SIGMOD symposium on Principles of database systems
A characterization of constant-time maintainability for BCNF database schemes
SIGMOD '88 Proceedings of the 1988 ACM SIGMOD international conference on Management of data
Efficient optimization of simple chase join expressions
ACM Transactions on Database Systems (TODS)
Updating databases in the weak instance model
PODS '89 Proceedings of the eighth ACM SIGACT-SIGMOD-SIGART symposium on Principles of database systems
Constant-time-maintainable BCNF database schemes
ACM Transactions on Database Systems (TODS)
Independence-reducible database schemes
Journal of the ACM (JACM)
Updating relational databases through weak instance interfaces
ACM Transactions on Database Systems (TODS)
Independence-reducible database schemes
Proceedings of the seventh ACM SIGACT-SIGMOD-SIGART symposium on Principles of database systems
Independent Database Schemes under Functional and Inclusion Dependencies
VLDB '87 Proceedings of the 13th International Conference on Very Large Data Bases
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It has been observed that, for some database schemes, users may have difficulties retrieving correct information, even for simple queries. The problem occurs when some implicit “piece” of information, defined on some subset of a relation scheme, is not explicitly represented in the database state. In this situation, users may be required to know how the state and the constraints interact before they can retrieve the information correctly.In this paper, the formal notion of embedded-completeness is proposed, and it is shown that schemes with this property avoid the problem described above. A polynomial-time algorithm is given to test whether a database scheme is independent and embedded-complete. Under the assumption of independence, it is shown that embedded-complete schemes allow efficient computation of optimal relational algebra expressions equivalent to the X-total projection, for any set of attributes X.