Efficiently updating materialized views
SIGMOD '86 Proceedings of the 1986 ACM SIGMOD international conference on Management of data
Updating derived relations: detecting irrelevant and autonomously computable updates
ACM Transactions on Database Systems (TODS)
Efficiency of a Good But Not Linear Set Union Algorithm
Journal of the ACM (JACM)
Variations on the Common Subexpression Problem
Journal of the ACM (JACM)
Locking Expressions for Increased Database Concurrency
Journal of the ACM (JACM)
Simplification by Cooperating Decision Procedures
ACM Transactions on Programming Languages and Systems (TOPLAS)
The notions of consistency and predicate locks in a database system
Communications of the ACM
The complexity of testing predicate locks
SIGMOD '79 Proceedings of the 1979 ACM SIGMOD international conference on Management of data
Adaptive Locking
Theory of Relational Databases
Theory of Relational Databases
Chasing constrained tuple-generating dependencies
PODS '96 Proceedings of the fifteenth ACM SIGACT-SIGMOD-SIGART symposium on Principles of database systems
Independence of logic database queries and update
PODS '90 Proceedings of the ninth ACM SIGACT-SIGMOD-SIGART symposium on Principles of database systems
Maintenance of implication integrity constraints under updates to constraints
The VLDB Journal — The International Journal on Very Large Data Bases
Records retention in relational database systems
Proceedings of the 17th ACM conference on Information and knowledge management
Detecting privacy violations in database publishing using disjoint queries
Proceedings of the 12th International Conference on Extending Database Technology: Advances in Database Technology
A framework for testing DBMS features
The VLDB Journal — The International Journal on Very Large Data Bases
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This paper presents an algorithm that decides whether two conjunctive query expressions always describe disjoint sets of tuples. The decision procedure solves an open problem identified by Blakeley, Coburn, and Larson: how to check whether an explicitly stored view relation must be recomputed after an update, taking into account functional dependencies. For nonconjunctive queries, the disjointness problem is NP-hard. For conjunctive queries, the time complexity of the algorithm given cannot be improved unless the reachability problem for directed graphs can be solved in sublinear time. The algorithm is novel in that it combines separate decision procedures for the theory of functional dependencies and for the theory of dense orders. Also, it uses tableaux that are capable of representing all six comparison operators , and ≠.